Search

The work in this paper incorporated printed circuit board (PCB) technology into micro-direct methanol fuel cells ^DMFCs) and conjectured and verified the performance degradation factors of PCB current collectors in μDMFCs by testing different designed configuration μDMFCs. The experiment results showed that all kinds of PCB coating can benefit from the porous stainless-steel plates covering to a great extent. At the end of 48 h discharging, μDMFCs with porous stainlesssteel plates between MEA and PCB coating achieved higher performance than those of the direct contacting series. It can be inferred from various types of experimental data that because of stainless-steel porous plate isolating, the impact of corrosion on the surface of the PCB electrode plate was reduced to a certain extent. The corrosion of the electrode plate was slowed down in the μDMFC discharging as a result of the passivation behavior on the iron surface and a decrease in corrosion current. Consequently, the attenuation of the PCB performance was delayed. The conclusion of this work explores a practical direction to enhance the cost-effectiveness of fuel cells, promoting the largescale application of DMFCs in the future. [ABSTRACT FROM AUTHOR]

The methanol steam reforming process involves variable heat absorption along the flow direction, resulting in a non-uniform temperature within the reactor. To improve the hydrogen production performance, this paper introduces an innovative solar-driven reactor, the Fresnel Lens Concentrated Collector Tubular Reactor (FLCCTR), which matches solar energy collection with the endothermic reforming process through optimized design. The heat flux density on the reactor's inner wall was determined using the Monte Carlo method. Subsequently, a 3D model was developed that integrates flow, heat and mass transfer, along with reforming kinetics. This model assessed the effects of inlet flow rate, temperature, steam-to-methanol ratio, and heat flux density type on hydrogen production performance. Results indicate that the inlet flow rate significantly affects performance, with the reactor maintaining a minimal radial temperature difference of 3.554K. It also indicated that non-uniform heat flux reduces the temperature increase and CO output by 36.84% at the outlet. • A novel reactor propelled by a Fresnel lens-based cavity solar collector is proposed. • Comparison of hydrogen production performance at two heat flux densities. • Lower CO production at non-uniform heat flux density. • The proposed new reactor has a small radial temperature difference. [ABSTRACT FROM AUTHOR]

A novel hybrid polymer electrolyte membrane (PEM) was developed for direct methanol fuel cell (DMFC) applications by incorporating sulfonated poly (ether ether ketone) (SPEEK) with a chromium‐based metal–organic framework (MOF), namely, BUT‐8(Cr). The incorporation of BUT‐8(Cr) significantly improved the dispersion of the MOF within the SPEEK matrix, leading to alterations in surface morphology and the creation of hydrophilic channels, as confirmed by SEM. Furthermore, the presence of an excess of sulfonic groups and the flexible structure of the MOF enhanced the physicochemical properties of the membrane, such as water uptake, proton conductivity and ion exchange capacity. Importantly, well‐defined rigid coordination structure of MOF effectively blocks methanol migration, resulting in a notably low methanol permeability value of 1.6 × 10−7 cm2 s−1, compared to Nafion 117 (20 × 10−7cm2s−1). For practical DMFC operation, the hybrid membrane (~0.75 wt.% MOF) exhibited a maximum power density of 88.6mWcm−2 with current density of 434.04 mAcm−2, outperforming Nafion 117 (73.4mWcm−2 and 380 mAcm−2 respectively) at same conditions. Our results suggest that the prepared SPEEK‐0.75 hybrid membrane holds a great promise as a PEM material for DMFC applications. [ABSTRACT FROM AUTHOR]

As Sweden takes its first steps towards a hydrogen-based economy, a strategic approach to infrastructure development for both storage and delivery becomes necessary. Although compressed hydrogen is currently the state-of-the-art, its low volumetric density and associated high capital costs pose challenges to widespread societal deployment of hydrogen. In order to avoid technological lock-in, alternatives storage technologies including chemical hydrides, e.g. methanol, ammonia, methane and LOHC, must also be explored. These alternatives offer higher hydrogen densities, safer handling, and compatibility with existing infrastructure. However, each hydride has unique chemical and physical properties, requires distinct feedstock and conversion processes, and interacts with the energy system in different ways, all of which influences their suitability for various applications. Therefore, a comprehensive evaluation of these alternative hydrogen storage technologies, as carried out in this article, is vital to allow for informed investment decisions and pave the way towards a successful and sustainable hydrogen economy. • Chemical hydrides have emerged as promising hydrogen storage alternatives. • Chemical hydrides facilitate cheaper global hydrogen trade. • Sweden's biogenic CO 2 emissions promote storage in methanol and methane. • Optimal storage choice depends on specific applications and their energy systems. • Chemical hydrides have high technological maturity. [ABSTRACT FROM AUTHOR]

Methanol is favored for its excellent physicochemical properties, becoming an ideal alternative fuel for engines. Adopting a dual-fuel injection mode of methanol port injection and gasoline direct injection (MPI + GDI) allows for more flexible injection strategies, enhancing the engine's power, efficiency, and emission performance. However, observing the processes of fuel injection, atomization, mixing, flow, and combustion in real engine cylinders is challenging, and controlling the fuel–air distribution and turbulence before engine ignition is difficult. Therefore, after validating the simulation model through optical engine bench experiments, this study investigated the performance and emission characteristics of MPI + GDI engines under various injection strategies. The results indicate that delaying the GDI injection timing decreases the uniformity of the fuel–air mixture and reduces cylinder pressure, corresponding to a retarded crank angle. Increasing GDI injection pressure enhances the fuel–air mixing, especially when the injection timing is later. Employing secondary injection and increasing the proportion of the second injection lead to poorer fuel–air uniformity in the cylinder, a decrease in peak pressure value, reduced nitrogen oxides (NOx) emissions, and a gradual increase in carbon monoxide (CO) and total hydrocarbons (THC). [ABSTRACT FROM AUTHOR]

The experimental data over CuO/ZnO/ZrO2 catalyst for a wide range of operating conditions were used to develop the kinetics of the reaction CO2 hydrogenation to methanol. Three kinetic models such as the power law model, the Graaf kinetic model, and the Park kinetic model were tested against the experimental data. Both the mechanistic models have been developed based on the Langmuir‐Hinshelwood‐Hougen‐Watson approach and are specific only to the methanol synthesis from CO/CO2 hydrogenation. In an attempt to reduce the number of parameters in the two models, the abridged forms of these models were also tried. Overall, 25 kinetic rate equations were tested and the best‐fit kinetic rate expression with optimized parameters was worked out. Both the integral and differential methods of kinetic analysis were employed and their efficacy in finding the best‐fit expression was compared. The MATLAB built‐in function fminsearch was employed to perform the regression of the data. The Graaf model in its parent form, but with the new optimized values of the parameters, was found to be the best‐fit rate model. The Graaf kinetics, with re‐estimated parameters, could be helpful in designing and simulating a methanol synthesis reactor operating on CO2 and H2 feed and utilizing a CuO/ZnO/ZrO2 catalyst. [ABSTRACT FROM AUTHOR]

Methanol is industrially generated from non-renewable fossil fuel sources. Owing to its widespread use in all domains, from synthesis of various chemicals to its use as an alternative fuel in the SI engines, finding a sustainable and renewable way of generating methanol would be one of the key achievements. Biomass-derived syngas for methanol generation would be one such example. However, bio-syngas has few drawbacks like (a) lower H 2 content when compared to the traditional SMR syngas, (b) the impurities present in bio-syngas are higher and need removal, (c) the biomass availability is scattered, just to name a few. In this work, we will be addressing the low H 2 -containing syngas for methanol generation process. Since limited literature is available on the experimental work on methanol generation from bio-syngas (without H 2 adjustment), this work aims to bridge the research gap by presenting experimental results on direct bio-syngas to methanol generation process. This work will address the experimental comparison between two syngas compositions: one H 2 excess and the other H 2 deficient. The composition of the first syngas, namely syn-1, used is like the one obtained from the SMR process. The composition of the second syngas, syn-2, is via the biomass gasification process. The H 2 /(CO+ CO 2 ) values in syn-1 and syn-2 were 3.54 and 1.08, respectively. The experimental setup consisted of a high-pressure microreactor, and a Cu/ZnO/ Al 2 O 3 commercial catalyst was used for the methanol generation process. The results from the experimental work were used to develop and validate the Aspen Plus® kinetic model. The validated model for lower H 2 -containing syngas for methanol generation process would be further used for the formulation of mathematical equation for methanol yield predictions. The experiments performed indicated that the methanol yield is favored at lower temperatures and higher pressure values of 483 K and 5 MPa for both syn-1 and syn-2. The results also indicated that the high CO 2 /CO ratio results in increased side reactions. The observed increase in the CH 4 selectivity in syn-2 when compared to syn-1 was the evidence for this increased side reactions. This is one of the key highlights as for SMR syngas-to-methanol conversion the CH 4 is sometimes assumed to be inert. Finally, the developed mathematical model predicted a maximum methanol yield of 21.06% for lower H 2 syngas at a temperature of 483 K, a pressure of 5 MPa and a space velocity of 1650 ml/h(g cat). The mass balance analysis suggests using 2.27 kg of syn-1 and 5.67 kg of syn-2 for production of one kg of methanol under a similar condition of 483 K, 5 MPa and 1650 ml/h(g cat). This validated model for methanol production will find its utility for methanol yield optimization and techno-economic analysis. [ABSTRACT FROM AUTHOR]

The escalating demand for renewable energy solutions and the imperative for efficient energy storage mechanisms have catalyzed the evolution of Power-to-X (PtX) technologies. Germany has the most PtX projects, accounting for 44% of all projects that have been reported. PtX encompasses a spectrum of processes engineered to convert surplus renewable energy into versatile energy carriers or chemical commodities, such as hydrogen, methane, or synthetic fuels. The Paramount to this domain is to synergistically harness renewable energy sources and hydrogen carriers to curtail waste and bolster sustainability. Central to achieving this synergy is the effective control of PtX processes, ensuring optimal performance, cost efficiency, and seamless integration within existing energy frameworks. This paper delves into the control processes and environmental prerequisites within the PtX landscape, elucidating key challenges, and strategies within this dynamic realm. While providing an initial overview of fundamental PtX process chains, this paper accentuates the critical role of geographical considerations. Subsequently, it conducts a thorough analysis of equipment modeling challenges, addressing performance metrics, operational requisites, and capital investments, particularly focusing on methanol and hydrogen production and storage. Through holistic examination, this paper endeavors to delineate the evolving landscape of PtX control processes and conditions, advancing our understanding of this expanding field. [Display omitted] • Comprehensive overview of PtX control process, challenges, strategies, and advancements. • Overview of PtX process chains and geographical conditions. • Analysis of equipment modeling challenges for methanol and hydrogen. • Addressing crucial storage challenges in PtX system. • Exploration of diverse influences on PtX control processes. [ABSTRACT FROM AUTHOR]

The present study reports the feasibility of a metal hydride (MH) purification technology employed for hydrogen produced via SRM using Cu/ZnO/Al 2 O 3 catalysts. The catalysts were synthesized by using the coprecipitation method and characterized by various techniques such as XRD, BET, FESEM, FETEM, EDX, XPS, TGA, FTIR, TPR and N 2 O chemiosorption. SRM was carried out under varying operating conditions viz., temperature 200–320 °C, water to methanol molar ratio (W/M) 1–1.7, and a feed flow rate (F M /W) 2.78–27.78 mmol·min−1g−1. Increasing the reaction temperature raised the methanol conversion rate, reaching 100 % at 300 °C, but it simultaneously promoted the formation of CO via rWGS. The increase in W/M ratio increases the methanol conversion rate while reducing the CO selectivity. The impact of feed flow rate (F CH3OH /W cat) on conversion and selectivity revealed that both methanol conversion and CO selectivity decreased at higher feed flow rates, but the rate of hydrogen production increased significantly. Specifically, raising F CH3OH /W cat from 2.78 to 27.8 mmol·min−1g−1 led to a decline of methanol conversion from 97% to 30% and CO selectivity from 0.8 % to 0 %, but the hydrogen production rate was increased from 180 to 570 mL min−1g−1 at 280 °C. The integration of MH based purification system to the production line resulted in the production of highly pure hydrogen (nearly 99% purity) using low-grade heat input (50–60 °C), for an impurity range of up to 40%. [Display omitted] • The Cu/ZnO/Al 2 O 3 catalyst was synthesized by using the coprecipitation method. • Catalyst was characterized using XRD, BET, FESEM, FETEM, EDX, XPS, TGA, and FTIR. • Cu/ZnO/Al 2 O 3 was tested for SRM reaction under various operating conditions. • Metal hydride-based hydrogen purification was employed for H 2 purification. • TCD was employed to analyize the gas composition during H 2 production and purification. [ABSTRACT FROM AUTHOR]

The direct partial oxidation of methane to methanol is a potentially transformative approach to upgrading methane to higher value molecules. Copper‐exchanged zeolites show potential to achieve this aim and have been extensively reported and reviewed in the open literature. This concept paper highlights selected works that point to knowledge gaps in this space, which opens opportunities for further breakthroughs. Specifically, these literature reports highlight the need for 1) additional research exploring how reactor operating conditions (space velocity, feed composition, temperature) can be optimized to improve methanol selectivity, 2) developing a better understanding of how the zeolite topology impacts the reactivity of methane, and 3) how different methods of loading copper into the zeolite impact reactivity. [ABSTRACT FROM AUTHOR]

Direct catalytic conversion of CO2 to methanol via renewable hydrogen has emerged as a promising technology among the various CO2 conversion techniques. However, efficient hydrogenation of CO2 using conventional Cu‐ZnO‐based catalysts, which are currently used for industrial methanol production from synthesis gas, remains a challenge due to inefficient energy conversion, poor stability and sluggish CO2 conversion kinetics. As the catalytic activity, stability and methanol selectivity of conventional Cu/ZnO catalysts are still insufficient for industrial applications, novel catalyst formulations using transition metals/metal oxides and supported noble metal nanostructures have emerged. Among them, intermetallic compounds are being explored for their unique electronic and crystalline structures, which can be tailored by controlled, precise, and seamless tuning of interatomic distances, specific arrangements and electronic structure to enhance their stability and activity for the selective hydrogenation of CO2 to methanol. In this context, intermetallic catalysts containing Pd, Cu and Ni combined with metal oxide nanoparticles (ZnO, Ga2O3, In2O3, etc.) have been shown to be more effective than the classical Cu‐ZnO‐Al2O3. This review analyses the progress made in the study of these intermetallic catalysts by analysing different aspects of their preparation, characterization, effects of promoters, support interactions, etc. Future research perspectives are discussed in the context of potential industrial applications of intermetallics for direct methanol production via CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop efficient anode materials for direct methanol fuel cell applications. The Ni foam was modified with Bi 2 O 3 - acetylene black-rGO to increase catalytic activity toward methanol oxidation. The Bi 2 O 3 was synthesized via a straightforward green technique. The characterization was achieved by using Fourier transform infrared spectroscopy and X-Ray diffraction analysis. The transmission electron microscope and field emission scanning electron microscope was utilized to evaluate the surface properties of catalysts, and energy-dispersive X-ray spectroscopy were employed to determine the chemical composition. Bi 2 O 3 particles with diameters ranging from 15 to 75 nm were crystal structures in the (111), (220), (311), and (342) crystal planes. The performance of methanol electrooxidation in an alkaline medium was investigated using cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry techniques. The surface coverage of the redox species was 2.04 × 10−5 mol g−1, and the diffusion coefficient ranged between 8.02 × 10−12 and 1.25 × 10−13 cm2 s−1. According to the obtained results, the Bi 2 O 3 - acetylene black-rGO modification enhanced the electrocatalytic activity of Ni foam against methanol oxidation in an alkaline medium. • This research aimed to produce effective anode materials for methanol fuel cells. • Facile method was used to generate composite electrocatalyst. • Bi 2 O 3 - acetylene black-reduced graphene oxide supported Ni foam used. [ABSTRACT FROM AUTHOR]

Methanol and hydrotreated vegetable oil (HVO) are complementary in the context of achieving ultra-low emission levels via low temperature combustion. HVO is a high-quality fuel fully compatible with compression ignition engines. Standalone methanol combustion is relatively straight-forward according to the Otto principle, with a spark ignited or in conventional dual-fuel ("liquid spark") engines. These two fuels have by far the largest reactivity span amongst commercially available alternatives, allowing to secure controllable partially premixed compression ignition with methanol–HVO emulsification. This study investigates the corrosion of aluminum, carbon steel, stainless steel, and a special alloy of MoC210M/25CrMo4+SH, exposed to different combinations of HVO, HVO without additives (HVOr), methanol, and emulsion stabilizing additives (1-octanol or 1-dodecanol). General corrosive properties are well determined for all these surrogates individually, but their mutual interactions have not been researched in the context of relevant engine components. The experimental research involved immersion of metal samples into the fuels at room temperature for a duration of 60 days. The surfaces of the metals were inspected visually and the dissolution of the metals into fuels was evaluated by analyzing the fuels' trace metal concentrations before and after the immersion test. Furthermore, this study compared the alterations in the chemical and physical properties of the fuels, such as density, kinematic viscosity, and distillation properties, due to possible corrosion products. Based on these results, methanol as 100% fuel or as blending component slightly increases the corrosion risk. Methanol had slight dissolving effect on aluminum (dissolving Al) and carbon steel (dissolving Zn). HVO, HVOr, and methanol–HVOr–co-solvents were compatible with the metals. No fuels induced visible corrosion on the metals' surfaces. If corrosion products were formed in the fuel samples, they did not affect fuel parameters. [ABSTRACT FROM AUTHOR]

The performance of Cu/ZnO/Al2O3 (CZA) catalysts promoted by addition of CeO2, MnO2 or ZrO2 in direct methanol production from unconventional syngas was experimentally investigated. The unconventional syngas used in this study contain 25% H2, 25% CO, 20% CH4, 20% CO2 and 10% N2, representing biomass‐derived syngas cultivated from an industrial wood chips pyrolysis plant. The catalysts were synthesised using co‐precipitation technique and tested for methanol synthesis in a fixed‐bed reactor. The activity test of the catalysts showed that the addition of CeO2 or ZrO2 to the CZA catalyst improved the methanol yield, albeit with lower selectivity, whereas adding MnO2 enhanced methanol selectivity but decreased the methanol yield. ZrO2‐promoted catalyst showed the best‐improved activity and stability. The calcined and spent catalysts were characterised using X‐ray diffraction (XRD), N2 physisorption, N2O chemisorption, hydrogen temperature‐programmed reduction (H2‐TPR) and X‐ray photoelectron spectroscopy (XPS). The characterisation results indicate that the catalytic activity is dependent on Cu dispersion, Cu‐active surface area, the catalyst reducibility, Brunauer–Emmett–Teller (BET) surface area and the Cu0/Cu+ ratio. In contrast, catalyst stability was related to the proportion of Cu+ among all surface Cu species. [ABSTRACT FROM AUTHOR]

At present, commercial Nafion membrane is not suitable for proton exchange membrane used in direct methanol fuel cell (DMFC) due to the severe methanol permeation phenomenon. This work reported the preparation and characterization of azide‐substituted polysulfone (PSU‐N3) and alkynyl‐substituted sulfonated polyvinyl alcohol (SAPVA) crosslinked in the matrix of Nafion membrane base on click chemistry applied in DMFC. The compatibility between PSU‐N3 and SAPVA is promoted due to the formation of crosslinked network structure. Key properties, including dimensional stability, oxidative stability, mechanical behavior, methanol permeability and proton conductivity, are compared with those of the recast Nafion membrane. The prepared blend membranes exhibit lower methanol permeability due to the crosslinked network and well‐dispersed microphase structure of PSU‐PVA in the Nafion matrix. The proton selectivity of the Nafion‐PSU‐PVA‐3 membrane is 9.16 × 104 S s/cm3, much higher than that of the recast Nafion membrane (2.82 × 104 S s/cm3). In DMFC single cell tests, the maximum power density of the Nafion‐PSU‐PVA‐3 membrane is 4.6 mW/cm2, about 58.6% higher than that of the recast Nafion membrane. All the results indicate that the prepared blend membranes have the potential to be applied in DMFC. [ABSTRACT FROM AUTHOR]

The exergy analysis of a direct method for the conversion of natural gas to methanol is reported in this work. The study is part of a process development effort to identify areas of improvement to the technology of direct conversion of natural gas to methanol. Prior to the exergy analysis, different configurations of the direct conversion process were developed and simulated. Two heat-integrated configurations designated as Case I and Case II were considered plausible. The exergy efficiency, excluding exergy of the rejected heat, of Case I and Case II were determined as 33% and 36%, respectively. The 9% increase in efficiency of Case II relative to Case I did not justify the installation of an expander and was therefore screened out. Exergy balance in Case I showed that a total of 56% of the exergy input was lost to internal consumption. The majority of exergy destruction was found to be due to the methanol synthesis reactor (36.0%), heat exchangers (30.1%) and combustion (25.0%). Further analyses of the losses across all heat exchangers indicated a nonlinear relationship between exergy destruction contribution and minimum approach temperature (ΔTmin), with a minimal at ΔTmin of 10 °C. The methanol product was determined to represent 18% of exergy input, excluding the air separation unit. The overall process efficiencies were found to be 18% (LHV) and 24% (LHV) for recycle split fractions of 90% and 98%, respectively. The results of this work would provide further insight into the exergy viability of the technology of direct conversion of natural gas to methanol. [ABSTRACT FROM AUTHOR]

Kinetic model development is integral for designing, redesigning, monitoring, and optimizing chemical processes. Of the various approaches used within this field, microkinetic modeling is a crucial tool that focuses on surface events to analyze overall and preferential reaction pathways. This work covers noticeable features of microkinetic modeling for three critical case studies: (i) ammonia to hydrogen, (ii) oxidative coupling of methane to chemicals, and (iii) carbon dioxide hydrogenation for methanol synthesis. We analyze how microkinetic modeling enables predicting and optimizing complex reaction networks, allowing the design of efficient and tailored catalysts with enhanced activity and selectivity. [ABSTRACT FROM AUTHOR]

Methanol oxidation plays a central role to implement sustainable energy economy, which is restricted by the sluggish reaction kinetics due to the multi‐electron transfer process accompanied by numerous sequential intermediate. In this study, an efficient cascade methanol oxidation reaction is catalyzed by single‐Ir‐atom catalyst at ultra‐low potential (<0.1 V) with the promotion of the thermal and electrochemical integration in a high temperature polymer electrolyte membrane electrolyzer. At the elevated temperature, the electron deficient Ir site with higher methanol affinity could spontaneous catalyze the CH3OH dehydrogenation to CO under the voltage, then the generated CO and H2 was electrochemically oxidized to CO2 and proton. However, the methanol cannot thermally decompose with the voltage absence, which confirm the indispensable of the coupling of thermal and electrochemical integration for the methanol oxidation. By assembling the methanol oxidation reaction with hydrogen evolution reaction with single‐Ir‐atom catalysts in the anode chamber, a max hydrogen production rate reaches 18 mol gIr−1 h−1, which is much greater than that of Ir nanoparticles and commercial Pt/C. This study also demonstrated the electrochemical methanol oxidation activity of the single atom catalysts, which broadens the renewable energy devices and the catalyst design by an integration concept. [ABSTRACT FROM AUTHOR]

A series of B-site Co3+-doped LaCu x Co 1-x O 3 (x = 1, 0.8, 0.6, 0.4, 0.2) perovskites were synthesized by solution combustion method and their physicochemical properties were comprehensively characterized. The perovskite-coated Cu foams were applied as monolithic catalysts for methanol steam reforming to produce H 2. Results showed that an appropriate amount of Co3+ doping led to the stabilization of crystal structure, the reduction of particle size, the improvement of chemical constitution, the enhancement of reduction behavior, the decrease of acidity, the increase of specific surface area, and the optimization of surface chemical state. The monolithic catalyst loaded with LaCu 0.4 Co 0.6 O 3 showed the highest methanol conversion rate and H 2 production rate, the lowest CO selectivity, the best stability and the lowest carbon deposition. However, excess Co3+ resulted in a degradation of the catalytic performance. The findings of this work suggested that introducing Co3+ might be a promising way to enhance the activity of Cu species for obtaining a better Cu-containing perovskite-based monolithic catalyst. [Display omitted] • Co3+-doped LaCuO 3 perovskites are prepared and used for methanol steam reforming. • The Co3+ doping significantly affects the physicochemical properties of perovskite. • LaCu 0.4 Co 0.6 O 3 exhibits the best performance due to its excellent characteristics. • Co3+ can effectively optimize the active center and enhance the activity of Cu0. [ABSTRACT FROM AUTHOR]

In response to climate change and the imperative for sustainable energy solutions, this study investigates the feasibility of producing green hydrogen and associated e-fuels (methane, methanol, and ammonia) using a renewable energy hybrid system in Dakhla, Morocco. Utilizing the System Advisor Model (SAM) software for simulation-based analysis, the research evaluates a hybrid system combining concentrated solar power (CSP) and photovoltaic (PV) plants against standalone counterparts. Various simulations comparing standalone PV and CSP plants with a novel CSP/PV hybrid concept were carried out. The hybrid system demonstrates significant promise, exhibiting increased annual energy yield and capacity factors up to 90%, leading to enhanced efficiency, performance, and cost savings with a Levelized Cost of Electricity (LCOE) approximating 17 cents/kWh. Furthermore, this paper conducts an in-depth exploration into the feasible production of hydrogen and its derived synthetic fuels utilizing hybrid renewable systems. The study provides a thorough examination of the production processes, yields, and efficiencies of hydrogen and its derivative e-fuels, with a focus on green hydrogen production through water electrolysis, CO2 hydrogenation, the Sabatier process, and the Haber-Bosch process. It sheds light on the potential applications of these fuels in the transportation sector, including in electric and hydrogen vehicles and aviation. The insights garnered are indispensable for crafting future strategies and policies in sustainable energy planning. These findings not only provide valuable direction for forthcoming initiatives in renewable energy but also underscore the pivotal role of hybridization in enhancing the efficient production and utilization of hydrogen within both renewable energy and transportation sectors. • PV and CSP systems to generate electricity for the Dakhla city was investigated. • A Hybrid system optimization has been proposed. • The Electricity surplus was used to produce hydrogen and hydrogen-based products. • Various scenarios for the heavy-duty application of e-fuel were presented and discussed. [ABSTRACT FROM AUTHOR]

In order to improve the output performance of direct methanol fuel cell, the finite-time thermodynamic model of direct methanol fuel cell is developed in this paper. Then, mathematical expressions for energy efficiency, power density, exergy efficiency and exergy coefficient of performance are derived. In addition, the effects of operating temperature, inlet pressure and membrane thickness on the performance of direct methanol fuel cells are considered. The results show that the exergetic performance coefficient not only considers the exergy loss rate to minimize the loss, but also the power density of the direct methanol fuel cell to maximize its power density and improve its efficiency. Therefore, the exergetic performance coefficient is a better performance criterion than conventional power and efficiency. In addition, increasing the inlet pressure and decreasing the membrane thickness can significantly improve the exergetic performance coefficient and energy efficiency. [ABSTRACT FROM AUTHOR]

So far, it is still extremely challenging to develop an efficient catalyst for deep oxidation of methanol at low temperature. Herein, we report the construction of the highly dispersed CuAg alloy on the surface of Ce0.90In0.10Oδ nanorods support for catalyzing methanol deep oxidation. The composition, structure and properties of catalysts were characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet‐visible (UV‐vis) spectroscopy and X‐ray photoelectron spectroscopy (XPS). The results show that the CuxAg100‐x/Ce0.90In0.10Oδ alloy catalysts exhibit superior catalytic activity and stability compared to pure Ag/Ce0.90In0.10Oδ, with the highest activity observed for Cu40Ag60/Ce0.90In0.10Oδ, accompanied by the light‐off temperature (T50) and full conversion temperature (T90) of 115 and 145 °C, respectively. This is attributed to the synergistic effect of CuAg alloy, which results in electron transfer, generating more Ag0, and enhanced interaction between CuAg alloy and the support, leading to increased Ce3+ content and higher oxygen vacancy concentration. This work successfully applies CuAg alloy catalysts in thermo‐catalytic reaction, offering promising prospects for CuAg alloy catalysts in the methanol deep oxidation. [ABSTRACT FROM AUTHOR]

The methanol‐to‐hydrocarbons (MTH) process involves the conversion of methanol, a C1 feedstock that can be produced from green sources, into hydrocarbons using shape‐selective microporous acidic catalysts – zeolite and zeotypes. This reaction yields a complex mixture of species, some of which are highly reactive and/or present in several isomeric forms, posing significant challenges for effluent analysis. Conventional gas‐phase chromatography (GC) is typically employed for the analysis of reaction products in laboratory flow reactors. However, GC is not suitable for the detection of highly reactive intermediates such as ketene or formaldehyde and is not suitable for kinetic studies under well defined low pressure conditions. Photoelectron–photoion coincidence (PEPICO) spectroscopy has emerged as a powerful analytical tool for unraveling complex compositions of catalytic effluents, but its availability is limited to a handful of facilities worldwide. Herein, PEPICO analysis of catalytic reactor effluents has been implemented at the FinEstBeAMS beamline of MAX IV Laboratory. The conversion of dimethyl ether (DME) on a zeolite catalyst (ZSM‐5‐MFI27) is used as a prototypical model reaction producing a wide distribution of hydrocarbon products. Since in zeolites methanol is quickly equilibrated with DME, this reaction can be used to probe vast sub‐networks of the full MTH process, while eliminating or at least slowing down methanol‐induced secondary reactions and catalyst deactivation. Quantitative discrimination of xylene isomers in the effluent stream is achieved by deconvoluting the coincidence photoelectron spectra. [ABSTRACT FROM AUTHOR]

Plasma catalytic CO2 hydrogenation to methanol over MnOx/ZrO2 catalyst was investigated in this work. A boosted methanol yield of 4.6 mg/h was obtained over MnOx/ZrO2 catalyst, while it was only 0.0 and 0.7 mg/h for ZrO2 and MnOx catalyst, respectively. The interaction between MnOx and ZrO2 was responsible for the enhanced methanol yield. It resulted in sufficient oxygen vacancy. The in situ DRIFT spectra was conducted to reveal the plasma catalytic CO2 hydrogenation to methanol reaction mechanism and the key intermediates of HCOO and CH3O species were determined. The sufficient oxygen vacancy promoted the formation of the key intermediates, especially the CH3O species. [ABSTRACT FROM AUTHOR]

The tunability of structural properties such as oxygen vacancies, Cu surface composition, reducibility of CuO, and basicity by solution combustion synthesised (SCS) Cu‐CeO2 catalysts was investigated. Five different fuels, viz. urea (U), tartaric acid (TA), citric acid (CA), ethylene glycol (EG) and oxalyl dihydrazide (ODH), were employed in the synthesis of the catalysts. Raman spectroscopy, O2‐TPD and XPS revealed that the urea synthesised catalyst had the highest concentration of oxygen vacancies, the amount of which was controlled by the fuel used. The oxygen vacancies were the catalytic sites for CO2 adsorption and promoted electron donation to Cu at the Cu‐CeO2 junction, thus improving H2 adsorption and spillover, which was beneficial for methanol synthesis. The better catalytic performance of the urea synthesised Cu‐CeO2 catalyst with a methanol STY of 163 gCH3OH kg−1cat h−1 compared to the other solution combustion synthesis fuels, was attributable to higher oxygen vacancies, more facile Cu reduction, larger Cu surface area and higher Cu surface composition. Based on the absence of the Cu+ species capable of directing the methanol synthesis reaction through the CO intermediate based on XPS data, we surmised that the formate route was the preferred pathway for the studied Cu‐CeO2 catalysts. [ABSTRACT FROM AUTHOR]

Density functional theory was employed to investigate methylidyne radical reaction on to the unsaturation of dipyrromethanol moiety through cycloaddition forming a six membered di(pyridin-2-yl)methanol followed by H-elimination via ring expansion. Time-dependent density functional theory (TD-DFT) simulations were performed to figure out the ultraviolet–visible spectrum of dipyrromethanol and di(pyridin-2-yl)methanol. Ultraviolet–visible spectrum of dipyrromethanol and di(pyridin-2-yl)methanol shows that two sharp absorption peaks were obtained at λmax = 161 nm and 206 nm for the reactant dipyrromethanol while a sharp peak was observed for the product di(pyridin-2-yl)methanol at shorter wavelength (λmax = 170 nm). The theoretical IR spectrum of dipyrromethanol and di(pyridin-2-yl)methanol shows that a significant red shift of 129 cm−1 was observed in the case of di(pyridin-2-yl)methanol due to presence of two strong intra-molecular hydrogen bonds, which indicates its higher stability than the dipyrromethanol. HOMO–LUMO energy gap calculations and natural bond orbital (NBO) analysis endorse the type of electronic transition for the desired product di(pyridin-2-yl)methanol is π–π*. The global reactivity analysis shows the electron donor and acceptor nature of dipyrromethanol and methylidyne radical, respectively. A potential energy surface is constructed via methylidyne radical addition, ring expansion, and hydrogen elimination transition states. Thermodynamics study and potential energy surface of the title reaction indicates its highly exothermicity and spontaneous in nature. [ABSTRACT FROM AUTHOR]

The catalytic performance of different molecular sieves in the alkylation of phenol with methanol to produce p‐cresol was evaluated, and the acidity and structure of the catalysts were characterized using N2 adsorption–desorption and Fourier transform infrared spectroscopy techniques. It was shown that the catalytic activity of molecular sieves was closely related to their acidic site number, specific surface area, and pore structure. Since Zeolite ZSM‐5 (Zeolites Socony Mobil No. 5) has a relatively small amount of strong acid as well as a small pore size, it is favorable for the diffusion of p‐cresol out of the pores. Therefore, focusing on ZSM‐5, the effects of operating conditions such as weight hourly space velocity (WHSV), phenol/methanol (P/M) ratio, and reaction temperature on the catalytic performance were investigated. The results showed that increasing the WHSV, P/M ratio, and reaction temperature improved the selectivity to cresol. In addition, X‐ray diffraction and Thermal Gravity/Differential Thermal Gravity characterization methods were also carried out for ZSM‐5, and it was found that the deactivation of ZSM‐5 was due to coke deposition and pore blockage on the active site and that the selectivity to cresol could be restored by regenerating the catalyst and covering the strong acid site, which resulted in the reduction of the strong acid site to increase the selectivity of the product. [ABSTRACT FROM AUTHOR]

This present work explored the possible use of sandbox seed (Hura crepitans) shell (SSS) waste as a feedstock for synthesizing green solid alkali biocatalyst in the microwave-aided sandbox oil (SBO) transesterification to obtain SBO biodiesel (SBOB). The solid catalyst was produced using a calcination method by burning raw SSS in the open air to obtain ash heated for 3 h in a furnace at 500 °C. The calcined sandbox shell ash (CSSA) produced was characterized using standard techniques to establish its catalytic potency. Also, a model was developed to simulate the process and examine the interactive effect of process input variables on SBOB yield using the Taguchi approach. The CSSA characterization showed it composed of K (44.99 %), Ca (1.54 %), and Mg (1.87 %) with crystalline compounds of K and Mg. The physisorption results gave a mean pore size of 18.142 nm and a surface area of 6.1125 m2/g. The best combination of the input variables determined for the process is a heating power of 450 W, methanol:SBO of 8:1, time of 1.5 min, and CSSA loading of 2 wt% with an optimum SBOB yield of 98.27 wt%. The SBOB produced met standard specifications for biodiesel. Microwave application to the SBO transesterification aided in rapidly completing the reaction. The study concluded that sandbox seeds and their shells are promising feedstock for cheap and sustainable biodiesel production. [Display omitted] • Novel biocatalyst from Sandbox shell wastes was synthesized and characterized. • Sandbox oil biodiesel was produced via transesterification with the biocatalyst. • The transesterification process was modeled and optimized by Taguchi method. • 98.27 wt% biodiesel yield was achieved using the optimum values obtained. • Sandbox oil biodiesel produced satisfied the standard specifications. [ABSTRACT FROM AUTHOR]

The oxidative carbonylation of methanol to synthesize dimethyl carbonate (DMC) has been extensively studied over Cu‐based catalysts, but the activity and selectivity are not high. The Co catalysts exhibit high DMC selectivity, but the difficulty in recycling homogeneous Co catalyst and the low conversion of heterogeneous Co catalyst limit the application of Co catalysts. Here, the core–shell ZIFs materials were synthesized and carbonized to obtain solid core–shell cobalt catalysts, and then the catalytic performance for methanol conversion to DMC was investigated. The CoNC@NC catalyst, carbonized from Z67@Z8 with Z67 as the core and Z8 as the shell, shows that the carbonized NC shell effectively suppressed the aggregation of Co NPs and the Co NPs were only 15.4 nm, which was much smaller than those of NC@CoNC (34.5 nm) and CoNC (48.1 nm) catalysts. Compared with the CoNC catalyst, CoNC@NC significantly improved the pulse chemisorption of CH3OH and CO, leading to a significant increase in methanol conversion from 6.9% to 17.1%. Furthermore, the deactivation rate of the CoNC@NC catalyst (22.8%) was much lower than that of CoNC (59.4%) after five reaction cycles. The results of this work provide a new strategy for the design and preparation of solid cobalt catalysts for the oxidative carbonylation of methanol to DMC. [ABSTRACT FROM AUTHOR]

Laminar flame speeds of methanol/air mixtures at 338–398 K are measured by the heat flux method, extending the range of equivalence ratio up to 2.1. And a new optimized methanol mechanism with 94 reactions is proposed by using the particle swarm algorithm, adjusting 20 Arrhenius pre‐exponential factors in their uncertainty domains. The optimized model is compared with eight methanol combustion mechanisms and experimental data published in recent years, covering a wide range of initial temperatures (298–1537 K), pressures (0.04–50 atm) and equivalence ratios (0.5–2.1). The results show that the optimized mechanism not only improves the accuracy of ignition delay time with rapid compression machine at low temperature but also moderately improve the description of laminar flame speed in lean and stoichiometric conditions. Meanwhile, the optimized model significantly enhances the prediction accuracy of CH3 and CH2O radical, and perfectly captures the evolution trend of HCO radical in laminar flat flame. Overall, the optimized mechanism provides the best overall description of the currently available measurements, leading to more accurate and comprehensive prediction of ignition delay time, laminar flame speed and species concentration. [ABSTRACT FROM AUTHOR]

A low‐cost, high‐performance alternative fuel to traditional fossil fuels is required due to rising energy demand, fossil fuel depletion, and rising prices. In this case, one of the green fuels could be synthesized using transesterification from waste‐fried edible oil (WFEO). The current study deals with neat diesel (D100) and waste‐fried edible oil biodiesel (B100) as the baseline fuels. By volume, a binary blend of 50% diesel and 50% WFEO biodiesel was prepared. The biodiesel/methanol/diesel mixture was considered a ternary blend under two different ternary ratios, such as B40M10D50 and B30M20D50, respectively. The fuel characterization and the rheological study were performed for all the fuel blends as per the ASTM standards. According to engine experimental results, the B30M20D50 blend has 25.42% higher brake thermal efficiency (BTE) than B100 but 3.4% lower than D100 at full load due to the higher methanol percentage. When compared with D100, adding 20% methanol to the ternary blend reduced brake‐specific fuel consumption (BSFC) by 33.34%. Both ternary blends increased NOx emissions by 27.38% and 22.97% compared to D100 but decreased them by 14.23% and 18.68% compared to B100. Both ternary blends produced 0.4 and 0.36 kg/kWh at lower loads, while the D100 and B100 produced 0.46 and 0.42 kg/kWh. Finally, the entropy‐weighted technique for order preference by similarity to the ideal solution (TOPSIS) multi‐criteria decision‐making method was used to determine the best blend for engine performance and emissions. The entropy‐weighted TOPSIS technique likewise found that a B30M20D50 ternary blend with 75% loading had the lowest emissions and best performance. [ABSTRACT FROM AUTHOR]

Plasma catalytic CO2 hydrogenation to methanol over MnOx/ZrO2 catalyst was investigated in this work. A boosted methanol yield of 4.6 mg/h was obtained over MnOx/ZrO2 catalyst, while it was only 0.0 and 0.7 mg/h for ZrO2 and MnOx catalyst, respectively. The interaction between MnOx and ZrO2 was responsible for the enhanced methanol yield. It resulted in sufficient oxygen vacancy. The in situ DRIFT spectra was conducted to reveal the plasma catalytic CO2 hydrogenation to methanol reaction mechanism and the key intermediates of HCOO and CH3O species were determined. The sufficient oxygen vacancy promoted the formation of the key intermediates, especially the CH3O species. [ABSTRACT FROM AUTHOR]

Anaerobic, acetogenic bacteria are well known for their ability to convert various one-carbon compounds, promising feedstocks for a future, sustainable biotechnology, to products such as acetate and biofuels. The model acetogen Acetobacterium woodii can grow on CO2, formate or methanol, but not on carbon monoxide, an important industrial waste product. Since hydrogenases are targets of CO inhibition, here, we genetically delete the two [FeFe] hydrogenases HydA2 and HydBA in A. woodii. We show that the ∆hydBA/hydA2 mutant indeed grows on CO and produces acetate, but only after a long adaptation period. SNP analyzes of CO-adapted cells reveal a mutation in the HycB2 subunit of the HydA2/HydB2/HydB3/Fdh-containing hydrogen-dependent CO2 reductase (HDCR). We observe an increase in ferredoxin-dependent CO2 reduction and vice versa by the HDCR in the absence of the HydA2 module and speculate that this is caused by the mutation in HycB2. In addition, the CO-adapted ∆hydBA/hydA2 mutant growing on formate has a final biomass twice of that of the wild type. Many acetogens, including Acetobacterium woodii, cannot grow on carbon monoxide and thus cannot be used as platform to detoxify industrial waste gas streams. Here, the authors solve the problem by knocking out the two [FeFe] hydrogenases HydA2 and HydBA in A. woodii. [ABSTRACT FROM AUTHOR]

A novel phosphine‐free ruthenium pincer complex based on an NNN pincer ligand has been prepared and fully characterized. The complex was subsequently employed as an efficient catalyst for the N‐methylation of amines and the direct N‐methylation of nitroarenes using methanol as a C1 source under mild reaction conditions following the borrowing‐hydrogen approach. Both of the catalytic transformations were performed with only catalytic amounts of base under closed air conditions without using any other additives. [ABSTRACT FROM AUTHOR]

Aqueous-phase reforming of methanol (APRM) is an important method for H 2 production, widely used in energy fields like polymer electrolyte membrane fuel cells (PEMFCs). However, traditional noble metal catalysts, being expensive and vulnerable to CO poisoning, restrict their practical application. Therefore, developing robust non-noble metal catalysts for efficient and sustainable H 2 production with low CO levels in APRM at low temperatures is highly significant. In this study, a novel approach was employed to synthesize carbon-encapsulated Cu catalyst via controlled pyrolysis, leading to Cu@CA-Val catalyst with excellent low-temperature catalytic activity. The optimal Cu@CA-Val-300 catalyst exhibited a high hydrogen production rate of 0.2–27.0 μmolH 2 /g cat /s over a wide temperature of 135–180 °C (base-free), surpassing the most Cu-based and Pt-based catalysts. The Cu@CA-Val-300 catalyst exhibited exceptional hydrothermal stability during continuous operation in a fixed reactor for 200 h. Efficient H 2 production was attributed to good wettability, enabling the diffusion of CH 3 OH and H 2 O molecules into Cu+/Cu0 sites for activation, with CO being suppressed and transformed through the formate formation. [Display omitted] • Cu@CA-Val catalyst displayed highly efficient H 2 production activity over a wide temperature range of 135–180 °C. • H 2 with high purity and low CO content was prepared. • The good wettability of the Cu@CA-Val catalyst improved its affinities towards the CH 3 OH/H 2 O solution. [ABSTRACT FROM AUTHOR]

A promising method was established for the determination of nine halobenzoquinones (HBQs) in potable water by membrane solid-phase extraction (MSPE) pretreatment and the liquid chromatography–mass spectrometry (LC-MS) method. A 500 mL water sample was taken for enrichment by the SDB-RPS membrane, which was previously activated by methanol and ultrapure water. The sample was eluted with methanol and re-dissolved with the initial mobile phase after nitrogen blowing. Then, it was detected in negative ion mode using the working curve, and HBQs were quantified by the external standard method. The linearity was satisfactory in the concentration range of 4-1000 ng/L, with correlation coefficients of 0.9963~0.9994. The recoveries were 73.5~126.6% at three spiked levels, with relative standard deviations (RSDs) of 6.8~15.5%. The limits of detection (LOD, S/N = 3) values were 0.1~0.7 ng/L. The results demonstrate that the MSPE-LC-MS method is reliable, rapid, and sensitive for the simultaneous analysis of nine HBPs in potable water. [ABSTRACT FROM AUTHOR]

Organic phosphoester (OPE) antioxidants are currently required due to their contribution to enhancing the quality of polymers, including polypropylene (PP). In this research, an integral methodology is presented for the efficient extraction of bis(2,4-dicumylphenyl) pentaerythritol diphosphite from industrial wastewater. Upon employing the solid-phase extraction (SPE) technique, the recovered compound is subjected to a comprehensive analysis of the recovered compound using high-performance liquid chromatography (HPLC), mass spectrometry (MS), thermal analysis (TGA), Fourier transforms infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). Subsequently, purified Bis(2,4-dicumylphenyl) pentaerythritol diphosphite was evaluated as a thermo-oxidative stabilizer after incorporation into PP resins. The relative standard deviation (RSD), Error (Er), linearity (R2), and percentage (%) recovery were less than 2.6, 2.5, more significant than 0.9995, and greater than 96%, respectively, for the inter-day and intra-day tests of the chromatographic method and the SPE. Except for chloroform, which was necessary due to the solubility properties of the investigated analyte, the use of environmentally friendly solvents, such as methanol and acetonitrile, was considered during the development of this research. The OPE extracted from industrial wastewater was characterized by FTIR, UV–Vis, DSC, TGA, and MS, allowing the elucidation of the structure of Bis(2,4-dicumylphenyl) pentaerythritol diphosphite (BDPD). The recovered OPE was mixed with PP resins, allowing it to improve its thermal properties and minimize its thermo-oxidative degradation. Organophosphorus flame retardant (OPE)' concentration in wastewater is alarming, ranging from 1179.0 to 4709.6 mg L−1. These exceed toxicity thresholds for aquatic organisms, emphasizing global environmental risks. Using a validated solid-phase extraction (SPE) technique with over 94% recovery, the study addresses concerns by removing organic contaminants and supporting circular economy principles. The high economic and environmental significance of recovering BDPD underscores the need for urgent global attention and intervention. [ABSTRACT FROM AUTHOR]

Thin films of CuO wrapped around a skeleton were synthesised using nickel foam (NF) as a carrier and g-C 3 N 4 was embedded in it to generate NF@Cu/g-C 3 N 4 monolithic catalysts. The slow kinetics of photocatalytic reduction of CO 2 and the low quantum efficiency achieved, which is directly related to the photocatalyst and reactor configurations, limit the wide application of this technology. In light of this, a novel pod-like NF@Cu/g-C 3 N 4 monolithic photomicroreactor system was developed in this study to improve the efficiency of visible light-responsive CO 2 reduction to methanol. Micro-morphology and pore volume characterization showed that the incorporation of CuO and g-C 3 N 4 significantly increased the specific surface area and pore volume of Ni foam. The novel monolithic photomicro reactor was evaluated using methanol yield as an indicator, and the experimental results showed that the performance of the mesoporous NF@Cu/g-C 3 N 4 photomicroreactor was significantly better than that of the NF@CuO photomicroreactor as well as the tubular reactor. The average CH 3 OH yields were 6.47 and 9.85 times higher than those of pure CuO and pure g-C 3 N 4. The results showed that the methanol concentration and yield tended to increase and then decrease with the increase in liquid flow rate. The experimental results fully demonstrate the superiority of the newly developed NF@Cu/g-C 3 N 4 monolithic photomicroreaction system in enhancing the CO 2 photoreduction performance. [ABSTRACT FROM AUTHOR]

The anodic methanol oxidation reaction (MOR) plays a crucial role in coupling with the cathodic hydrogen evolution reaction (HER) and enables the sustainable production of the high‐valued formate. Nickel‐based hydroxide (Ni(OH)2) as MOR electrocatalyst has attracted enormous attention. However, the key factor determining the intrinsic catalytic activity remains unknown, which significantly hinders the further development of Ni(OH)2 electrocatalyst. Here, we found that the dx2-y2 ${{d}_{{x}^{2}-{y}^{2}}}$ electronic state within antibonding bands plays a decisive role in the whole MOR process. The onset potential depends on the deprotonation ability (Ni2+ to Ni3+), which was closely related to the band center of dx2-y2 ${{d}_{{x}^{2}-{y}^{2}}}$ orbital. The closer of dx2-y2 ${{d}_{{x}^{2}-{y}^{2}}}$ orbital to the Fermi level showed the stronger the deprotonation ability. Meanwhile, in the high potential region, the broadening of dx2-y2 ${{d}_{{x}^{2}-{y}^{2}}}$ orbital would facilitate the electron transfer from methanol to catalysts (Ni3+ to Ni2+), further enhancing the catalytic properties. Our work for the first time clarifies the intrinsic relationship between dx2-y2 ${{d}_{{x}^{2}-{y}^{2}}}$ electronic state and the MOR activities, which adds a new layer of understanding to the methanol electrooxidation research scene. [ABSTRACT FROM AUTHOR]

Electrocatalytic carbonylation of CO and CH3OH to dimethyl carbonate (DMC) on metallic palladium (Pd) electrode offers a promising strategy for C1 valorization at the anode. However, its broader application is limited by the high working potential and the low DMC selectivity accompanied with severe methanol self‐oxidation. Herein, our theoretical analysis of the intermediate adsorption interactions on both Pd0 and Pd4+ surfaces revealed that inevitable reconstruction of Pd surface under strongly oxidative potential diminishes its CO adsorption capacity, thus damaging the DMC formation. Further theoretical modeling indicates that doping Pd with Cu not only stabilizes low‐valence Pd in oxidative environments but also lowers the overall energy barrier for DMC formation. Guided by this insight, we developed a facile two‐step thermal shock method to prepare PdCu alloy electrocatalysts for DMC. Remarkably, the predicted Pd3Cu demonstrated the highest DMC selectivity among existing Pd‐based electrocatalysts, reaching a peaked DMC selectivity of 93 % at 1.0 V versus Ag/AgCl electrode. (Quasi) in situ spectra investigations further confirmed the predicted dual role of Cu dopant in promoting Pd‐catalyzed DMC formation. [ABSTRACT FROM AUTHOR]

Background: Melia azedarach is known as a medicinal plant that has wide biological activities such as analgesic, antibacterial, and antifungal effects and is used to treat a wide range of diseases such as diarrhea, malaria, and various skin diseases. However, optimizing the extraction of valuable secondary metabolites of M. azedarach using alternative extraction methods has not been investigated. This research aims to develop an effective, fast, and environmentally friendly extraction method using Ultrasound-assisted extraction, methanol and temperature to optimize the extraction of two secondary metabolites, lupeol and stigmasterol, from young roots of M. azedarach using the response surface methodology. Methods: Box-behnken design was applied to optimize different factors (solvent, temperature, and ultrasonication time). The amounts of lupeol and stigmasterol in the root of M. azedarach were detected by the HPLC-DAD. The required time for the analysis of each sample by the HPLC-DAD system was considered to be 8 min. Results: The results indicated that the highest amount of lupeol (7.82 mg/g DW) and stigmasterol (6.76 mg/g DW) was obtained using 50% methanol at 45 °C and ultrasonication for 30 min, and 50% methanol in 35 °C, and ultrasonication for 30 min, respectively. Using the response surface methodology, the predicted conditions for lupeol and stigmasterol from root of M. azedarach were as follows; lupeol: 100% methanol, temperature 45 °C and ultrasonication time 40 min (14.540 mg/g DW) and stigmasterol 43.75% methanol, temperature 34.4 °C and ultrasonication time 25.3 min (5.832 mg/g DW). Conclusions: The results showed that the amount of secondary metabolites lupeol and stigmasterol in the root of M. azedarach could be improved by optimizing the extraction process utilizing response surface methodology. [ABSTRACT FROM AUTHOR]

The advancement of semiconductor photocatalysis is acknowledged for its prowess as an eco-friendly, energy-efficient, and cost-effective method facilitating diverse organic transformations, including CO 2 photoreduction. Despite its merits, there remains room for enhancing the selectivity and efficiency of these photocatalysts. In this study, we successfully synthesized heterojunction nanocomposites comprising CdS and Bi 2 WO 6 semiconductors to drive the CO 2 -to-methanol conversion, achieving a maximum yield of 9450 μmol/g. Notably, CO (1048 μmol/g) and H 2 (482 μmol/g) were also produced using water within a 16-h photocatalytic period, yielding an average production rate of ∼590 μmol/g-h. Triethylamine played a crucial role by providing electrons to the reaction system. The recovered photocatalyst exhibited consistent performance over five cycles of photoreduction experiments. Various spectroscopic and microscopic techniques were employed to analyze the optical, catalytic, and morphological properties of both the fresh and recovered photocatalysts. The introduced S-scheme heterojunction photocatalyst stands out for its efficient charge carrier separation, enhancing redox capacity, and holds promise as a source for novel strategies to improve the efficiency of CO 2 photoreduction experiments. [Display omitted] [ABSTRACT FROM AUTHOR]

Machine learning (ML) force fields are revolutionizing molecular dynamics (MD) simulations as they bypass the computational cost associated with ab initio methods but do not sacrifice accuracy in the process. In this work, the GPyTorch library is used to create Gaussian process regression (GPR) models that are interfaced with the next‐generation ML force field FFLUX. These models predict atomic properties of different molecular configurations that appear in a progressing MD simulation. An improved kernel function is utilized to correctly capture the periodicity of the input descriptors. The first FFLUX molecular simulations of ammonia, methanol, and malondialdehyde with the updated kernel are performed. Geometry optimizations with the GPR models result in highly accurate final structures with a maximum root‐mean‐squared deviation of 0.064 Å and sub‐kJ mol−1 total energy predictions. Additionally, the models are tested in 298 K MD simulations with FFLUX to benchmark for robustness. The resulting energy and force predictions throughout the simulation are in excellent agreement with ab initio data for ammonia and methanol but decrease in quality for malondialdehyde due to the increased system complexity. GPR model improvements are discussed, which will ensure the future scalability to larger systems. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive techno-economic analysis of the world's first large-scale commercial Power-to-X (PtX) plant in Kassø, Denmark. This innovative facility combines solar photovoltaic (PV), an electrical grid, green hydrogen production, methanol synthesis, and district heating in an integrated system. We conduct an in-depth analysis to explore optimal operating conditions, the potential for sector coupling within the power and heat sectors, and the economic feasibility of the integrated system. In particular, we study different scenarios considering changes in solar PV power generation, electricity market price, CO 2 price, and methanol price to explore their impacts on the system performance. Our results show that the electrolyzer's operation, a pivotal component of the system, heavily depends on the electricity spot price as well as the methanol price. Based on the green production of methanol, a premium price of 4800 DKK/t (0.64 €/t) is considered in this study (selling price of 8400 DKK/t). The results show that in case of high electricity prices (2022 spot market) or no premium price for methanol, the optimum annual production of methanol decreases by 58% and 67%, respectively. Furthermore, we observe that the variability of solar power output significantly impacts the plant's performance and economic viability, as it supplies about 30% of the plant's power consumption. Although the results are unique to the Kassø plant, the study's techniques and insights can be applied to other comparable systems around the world. The study also highlights how crucial it is to take market, climate, and technical factors into account when developing and running integrated energy systems. • Techno-economic analysis of the world's first large-scale commercial Power-to-X (PtX) plant in Kassø, Denmark. • Insights to optimal operating conditions, sector coupling potential, and economic feasibility of Power-to-Methanol plants. • Analysis of the impact of market dynamics on the operational efficiency and economic viability of the integrated plant. • Study of the role of intermittent solar power and its impact on the performance and economic sustainability of the plant. [ABSTRACT FROM AUTHOR]

Methanol oxidation reaction (MOR) is used to provide electrical energy via direct methanol fuel cell (DMFC), which requires a practical design of electrocatalysts to accelerate the sluggish MOR. In this study, we successfully fabricated the carbon black nanoparticles/graphite ceramic electrode (CBNPs/GCE) supported metal-organic frameworks (MOFs) and decorated with nickel nanoparticles (NiNPs) as a new type nanocomposite modified electrode (NiNPs/MOFs/CBNPs/GCE) via a chemical and an electrochemical process, respectively. The surface morphology and structure of the synthesized nanocomposite materials and modified electrodes were characterized using field emission scanning electron microscopy, energy dispersive X-ray analysis, Fourier transform infrared spectroscopy, X-ray diffraction and thermogravimetric analysis. Then, the NiNPs/MOFs/CBNPs/GCE was used as a non-platinum electrocatalyst for electrocatalytic oxidation of methanol in alkaline media. The obtained results show the efficient electrocatalytic activity of the NiNPs/MOFs/CBNPs/GCE toward the MOR with high anodic peak current density (J pa = 34.8 mA cm−2) compared with the other prepared electrocatalysts; MOFs/CCE, NiNPs/CCE, MOFs/CBNPs/GCE, NiNPs/CBNPs/GCE, and NiNPs/MOFs/CCE, due to the synergistic effect of nanocomposite components; NiNPs, MOFs and CBNPs. The prepared electrocatalyst; NiNPs/MOFs/CBNPs/GCE, not only shows a high electrochemically active surface area (ECSA = 2.15 cm2) but also has long-term durability in MOR. In general, it can be said the NiNPs/MOFs/CBNPs/GCE is a promising candidate for application in DMFC. The preparation of the new type nanocomposite, construction processes of the NiNPs/MOFs/CBNPs/GCE and its application in MOR. [Display omitted] • The present MOFs was synthesized by a simple and rapid solvothermal method. • The dropped MOFs at the surface of CBNPs/GCE was decorated with NiNPs to fabricate the NiNPs/MOFs/CBNPs/GCE. • The synthesized nanocomposite and modified electrodes were characterized by the appropriated methods. • The NiNPs/MOFs/CBNPs/GCE was used as a potent electrocatalyst for MOR in alkaline media. • The NiNPs/MOFs/CBNPs/GCE displayed enhanced electrocatalytic activity toward MOR with high stability and durability. [ABSTRACT FROM AUTHOR]

Methanol steam reforming (MSR) has been used for in-situ hydrogen production, while hydrogen purification remains a technical challenge to limit the applications of using hydrogen for fuel cells. This study presents a pure hydrogen generation system (PHGS) by integrating MSR and hydrogen purification modules, this system enables low-temperature reforming and high-temperature purification to achieve high yield and recovery of hydrogen. To investigate the combined effects of feedstock flow rates and pressure on MSR and purification, the performance of each module and overall PHGS system were tested. The results showed that PHGS can stably produce high purity hydrogen (>99.99%) under different conditions, the synergistic effects of two modules lead to hydrogen yield exceeding the numerical sum of individual modules. At methanol feed rate of 1.00 g/min and system pressure of 5.0 bar, the pure hydrogen flow rate, CO content, pure hydrogen yield, hydrogen recovery and thermal power output were tested about 1.70 ± 0.01 L/min, 2.4 ± 0.1 ppm, 81.1 ± 0.5%, 87.6 ± 0.5% and 350 W. The PHGS can deliver up to 500 W of thermal power and is suitable for small range-extended electric vehicles. Our work on the developed PHGS can provide a significant reference for future practical applications of systems combining MSR and membrane purification. [Display omitted] • A separated system based on MSR and Pd membrane is proposed for hydrogen generation. • The effects of feed rate and pressure on system and its modules are investigated. • The system can generate 350 W of high-purity H 2 with an H 2 recovery of 87.6%. [ABSTRACT FROM AUTHOR]

In this study, three-dimensional modelling and simulation of a high-power six-cylinder hydrogen-blended methanol engine with direct hydrogen injection and methanol port injection were conducted using the simulation software CONVERGE. The control variable method was used to study the effects of hydrogen nozzle diameters of 1, 2, 3, and 4 mm on the in-cylinder airflow movement, hydrogen distribution, combustion, and emission characteristics of the hydrogen-blended methanol engine. The results showed that, with an increase in the hydrogen nozzle diameter, the injection duration was shortened, the distribution of hydrogen in the cylinder tended to be uniform, and the speed of flame propagation in the cylinder decreased. When the nozzle diameter was small, noticeable hydrogen accumulation occurred near the spark plug at the time of ignition, which accelerated flame propagation. Compared with increasing the diameter of the hydrogen nozzle, reducing the diameter of the nozzle caused the peak cylinder pressure and peak heat release rate to increase significantly; the ignition delay period was shortened; the mean indicated pressure and indicated thermal efficiency increased; and the emissions of CO, HC, and unburned methanol decreased, but the NO x emissions increased. Compared with pure methanol engines, hydrogen blending can optimise the combustion of methanol engines to a certain extent, improve power performance, and reduce the emissions of unburned methanol and formaldehyde. Therefore, a hydrogen nozzle diameter of 2 mm is considered the best solution for a hydrogen-blended methanol engine. • Hydrogen direct injection and methanol port injection. • Hydrogen-blended methanol engine has better combustion characteristics. • The hydrogen distribution under different hydrogen nozzle diameters was compared. • The engine with a hydrogen nozzle diameter of 2 mm has the best overall performance. [ABSTRACT FROM AUTHOR]

A series of Cu-ZnO-ZrO2 (CCZ) catalysts were prepared by the solvothermal method with different solvothermal times (1 h, 3 h, 6 h, and 12 h). The physicochemical properties of these catalysts and the catalytic performance for CO2 hydrogenation to methanol were studied. The highest methanol yield was achieved when the solvothermal time was 6 h (CCZ-6). Furthermore, we found that the copper surface area (SCu) increases and then decreases with an increase in the solvothermal time and that there is a strong correlation between the methanol yield and the SCu. This research highlights the crucial influence of the solvothermal time on the structure and catalytic behavior of Cu-ZnO-ZrO2 catalysts, providing a valuable reference for the development of efficient catalysts. [ABSTRACT FROM AUTHOR]

The demand for environmentally friendly types of energy is growing all over the world, which naturally increases the intensity of studies on fuel mixtures that have high contents of hydrogen. In this case, methanol steam reforming is a leading effective research area, as it is a process with low energy consumption. The results of the steam reforming of methanol on synthesized catalysts by the solution combustion synthesis (SCS), self-propagating high-temperature synthesis (SHS), and moisture impregnation capacity methods are presented. A study was conducted to evaluate the activity of Cu-Ce-Al catalysts with varying ratios of components for hydrogen production, comparing the SCS method with the other mentioned methods. The methanol conversion reached 99% and the selectivity of H2 was 88% at 500 °C. The study showed that the replacement of Al3+ ions with Cu2+ and Ce3+ cations leads to the formation of spinels, such as CuAl2O4 and CeAlO3. As a consequence, the CuAl2O4 and CeAlO3 lattice parameters increase because of the difference in the ionic radii of Al3+ (0.53 Å), Cu2+ (0.73 Å), and Ce3+ (1.07 Å). Advantages of SCS catalysts in the process of the steam reforming of methanol have been demonstrated. The goal of this research is to create a new catalyst for methanol's conversion into hydrogen-containing fuel mixtures, the production of which, in the future, will be a huge step in the transition to more energy-efficient and environmentally friendly methods of their synthesis. [ABSTRACT FROM AUTHOR]

Since the International Maritime Organization has paved the way towards zero emissions, more frequent applications of transition fuels in newly constructed ships have been observed. Fuels such as LNG or methanol are characterised by lower emissions when burned in engines. In order to diminish fuel consumption, and hence the rate of emission, support for the performance of a ship's engines with energy from renewable sources such as photovoltaic (PV) installations is increasingly common. The efficiency of PV panels decreases with an increase in temperature, and it is therefore important to cool them. However, the cooling systems for PV panels impose additional financial outlays as well as a higher demand for electric power, which is needed to run the circulating pumps. A natural cooling process can occur in some vessels via high sea waves, when the ship's decks are flooded by outboard water, although such cooling has an accidental and periodic character, as it results from weather conditions. Despite this, its potential demands a closer examination. This paper presents experimental research carried out with an experimental setup that allowed us to simulate the process of flooding of a PV panel with water waves of various frequencies, resulting from choppy periods at sea. Depending on the weather conditions and the character of flooding, our results indicate that an increase in the power of the PV module of about 18% is obtainable. Our research shows that when the intervals between flooding are longer, the periodic character of the temperature changes obtained by flooding the front surface of a PV panel with water is more distinctive. [ABSTRACT FROM AUTHOR]