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The development of advanced efficient and durable non-precious metal-based anode catalysts for photo-assisted direct methanol fuel cells remains a significant challenge. In this study, Ce-doped Co3O4 (Ce–Co3O4) was prepared by a three-step process involving hydrothermal synthesis, cation exchange and calcination. The introduction of Ce can not only induce more Co3+ with oxidation properties, but also expand the light absorption range and improve the separation efficiency of photogenerated electron–hole pairs. In an alkaline solution and under visible light irradiation, Ce–Co3O4 showed high current density (31.4 A g−1), high photo-response current (3.52 A g−1) and good long-term stability (the current density retention was 82% after 13 h under visible light irradiation). The reaction mechanism for the photo-assisted methanol oxidation was investigated by a series of optical characterization studies (UV-vis diffuse reflectance spectroscopy, Mott–Schottky, photoluminescence spectroscopy, and electron paramagnetic resonance). The results indicated that the strong oxidative photogenerated hole (h+), ˙OH, and ˙O2− were beneficial for the oxidation of methanol and COads. This study provides a good idea for the design of efficient non-precious metal based anode catalysts for photo-assisted direct methanol fuel cells. [ABSTRACT FROM AUTHOR]

Direct synthesis of dimethyl carbonate (DMC) from CO2 and CH3OH holds significant economic and environmental value. Numerous catalysts have been employed for this reaction, yet further enhancement of its activity requires a deeper understanding of the catalyst's structure–activity relationship and catalytic mechanism. In this study, we utilized structurally well-defined and highly tunable MOF-808 as a research platform. Functionalizing MOF-808 with ethylenediamine (MOF-808-ED) boosted the space time yield of DMC from 3.25 mmol g−1 h−1 to 7.23 mmol g−1 h−1. The experimental results demonstrate that the reaction involves acid–base synergistic catalysis, where an appropriate balance of acid–base site content is crucial for CO2 and CH3OH to produce DMC, as it facilitates the formation of the key intermediates (CH3OCOO*). Additionally, the nucleophilicity of N is stronger than that of O, further promoting the catalyst's enrichment and activation of CO2. Finally, employing in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) testing, we elucidated the mechanism by which the MOF-808-ED catalyst, with –NH2 as base sites and Zr as acid sites, facilitates the synergistic catalysis of the reaction. This study provides insights into the synergistic effects of acid–base sites on the synthesis of DMC from CO2 and methanol, offering valuable guidance for the development of high-performance catalysts. [ABSTRACT FROM AUTHOR]

Green methanol is a renewable fuel with great advantages when used in a spark ignition combustion process. Methanol has a comparatively high enthalpy of vaporization, leading to lower combustion temperatures as compared to gasoline combustion, and, hence, lower wall heat losses as well as a reduced tendency to pre‐ignition. Therefore, a brake efficiency of more than 40 % (this is comparable to diesel engines!) and furthermore minimal emissions, even at cold start, are possible. The serial combination with an electric powertrain provides a disconnection of the load demand of the powertrain and the operating point of the combustion engine. In this case, a high volumetric and gravimetric power density, easy energy storage and proven infrastructure of fuel distribution are combined with electric driving, high efficiencies, minimal emissions, and a closed carbon cycle for the energy provision. [ABSTRACT FROM AUTHOR]

Proton-conductor solid oxide fuel cells (PC–SOFCs) have demonstrated innovative capabilities in energy applications, particularly for the efficient transformation of biomass fuels into hydrogen for power generation. Methanol, a readily available and economical biomass fuel with a high hydrogen content, has shown significant potential for waste utilization and energy recovery. Consequently, this study employed methanol as a fuel for PC-SOFCs and investigated the optimal operating conditions through meticulously designed experiments. This study also enhanced the cell performance through the co-reforming of steam and methanol, demonstrating that the introduction of steam during the methanol-reforming process significantly improved cell efficiency. At a 30 % methanol fuel concentration and a 700 °C operating temperature, co-reforming increased the maximum power density (MPD) from 0.269 to 0.352 W cm−2. Additionally, integrating Ru-GDC nanofiber catalysts into the anodic dendritic microchannels enabled the creation of an in-situ catalytic cracking reactor, further boosting MPD to 0.412 W cm−2. The catalyst-equipped cell demonstrated stable operation for continuous 102 h at a current density of 0.6 A cm−2, with no performance decline, thereby confirming the exceptional long-term stability of the system. [Display omitted] [ABSTRACT FROM AUTHOR]

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]

Methanol has significant potential as an alternative fuel for internal combustion engines. Using methanol–gasoline blends with lean-burn technology in traditional spark-ignition engines can enhance fuel economy and reduce emissions. This paper investigates the effects of lean burn on the combustion and emissions in a commercial direct-injection gasoline engine fueled with methanol–gasoline blends. The lean-burn mode is adjusted by controlling the injection strategy. The results show that homogeneous lean burn (HLB) has earlier combustion phase and better power performance when the excess air ratio (λ) is less than 1.3, while its combustion phase extends more than stratified lean burn (SLB) when λ exceeds 1.4. Both lean-burn modes achieve optimal fuel economy at λ = 1.2–1.3. Under stable conditions, BSFC decreases with higher methanol blending ratios, with SLB being more economical at low blending ratios and HLB at higher ratios. The lowest HC and particulate matter emissions for both modes are achieved around λ = 1.3. SLB has lower NOX emissions when λ < 1.3, while HLB shows lower NOX emissions when λ > 1.3. The particulate size distribution is bimodal for blending lean-burn conditions, with SLB having the highest nucleation mode peak and HLB the highest accumulation mode peak. M20 (20% volume of methanol) corresponds to the highest particle emissions under lean-burn conditions. This study can provide a deeper understanding of methanol–gasoline blending lean burn, and provide a reference for emission control of spark-ignition engines. [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]

Expanding the application of methanol fuel cells in the energy economy is only feasible when a low-cost or highly CO-tolerant electrocatalyst replaces Pt catalysts to enhance the electrocatalytic properties of Pt. In this study, a PtAu thin film was produced at the liquid-liquid interface through the simple reduction of [Pt(cod)Cl2] and [Au(PPh3)Cl] complexes. The resulting thin film was directly transferred onto a glassy carbon electrode (without the application of Nafion™) and used as an electrocatalyst in the methanol oxidation reaction. Experimental and theoretical results both confirmed that PtAu exhibits lower CO poisoning compared to PtPd or Pt films. The high jf/jb ratio (where jf is the maximum current of the anodic peak in the forward route and jb is the maximum of peak current in the backward route), and theoretically calculated adsorption energies for PtAu thin film showed higher CO tolerance compared to Pt or PtPd thin film electrocatalysts. [ABSTRACT FROM AUTHOR]

Like batteries, fuel cells provide an inherently clean source of energy with no adverse environmental impact during operation. The utilization of methanol as a fuel is advantageous: it has an energy density of about 6 kWh/kg, which is, much higher than that of other commercialized batteries. This review is focused on the core of a DMFC, i.e., the symmetric membrane, in particular on the block copolymers used for its preparation as an alternative to well-known Nafion. The synthesis of block copolymer ionomers based on different building block types, with special emphasis on the critical issue of methanol permeability and proton/methanol selectivity, as well as the effect of block length and crosslinking are described and discussed. [ABSTRACT FROM AUTHOR]

This work developed new electrocatalysts for direct alcohol oxidation fuel cells (DAFCs) by using graphene and reduced graphene oxides (GO and rGO) as supporting nanomaterials for copper–nickel (CuNi) nanocomposites. The manufacture of CuNi, CuNi-GO, and CuNi-rGO nanocomposites was realized through the adaptation of Hummer's method and hydrothermal techniques, with subsequent analysis using a range of analytical tools. The electrocatalytic behavior of these materials in DAFCs, with methanol and ethanol as the fuels, was scrutinized through various methods, including cyclic voltammetry, linear sweep, chronoamperometry, and electrochemical impedance spectroscopy. This investigation also assessed the stability and charge transfer dynamics. The rGO-based CuNi nanocomposite demonstrated a remarkable performance boost, showing increases of approximately 319.6% for methanol and 252.6% for ethanol oxidation compared to bare CuNi. The integration of silver nanoparticles into the Ag-CuNi-rGO electrode led to a current density surge to 679.3 mA/g, which signifies enhancements of 254.2% and 812.6% relative to the CuNi-rGO and CuNi electrodes, respectively. These enhancements are ascribed to the augmented densities of hot sites and the synergistic interactions within the nanocatalysts. The findings underscore the potential of Ag and rGO as effective supports for CuNi nanocomposites, amplifying their catalytic efficiency in DAFC applications. [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]

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]

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]

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]

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]

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]

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]

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 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]

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 purpose of this work was to study the catalytic activity for the conversion of methanol into formaldehyde, dimethyl ether, methyl formate, dimethoxymethanane of zeolite catalysts - based on natural clinoptilolite and its modified Co2+, Cu2+, Mo2+, Cr2+ forms (Cl-X). The yield was 14.3% in the naturalclinoptilolite, 27.8% in the Co2+-modified sample, and 37.3% in the Cu2+-modified sample, correspondingly. The introduction of relatively small amounts of Co2+ and Cu2+ cations into the catalyst led to an increase in the activity of the catalysts. The effect of partial pressure of CH3OH on the yield of DME was studied (maximum yield of 37.3%, mol. DME is achieved at the ratio CH3OH:O2 = 3:1). The decrease in the reaction temperature from 523 to 423 K led to an increase in the yield of DMM, and the formation of dimethyl ether and methyl formate increased with an increase in temperature to 623 K. [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]

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]

This article explores the challenges and potential solutions for decarbonizing marine transportation. It discusses the environmental impact of the industry, including greenhouse gas emissions and pollution, and the need for alternative fuels. The advantages and disadvantages of hydrogen, ammonia, methanol, and battery energy storage systems are examined as potential alternatives. The article also addresses the challenges and considerations associated with each fuel, such as cost, storage, safety concerns, and infrastructure requirements. The ongoing research and development efforts in these areas are emphasized, as well as the need for comprehensive solutions to achieve zero-emission vessels. The article showcases various projects focused on advancing the use of methanol fuel in maritime transportation, including the production of methanol from renewable sources, the development of methanol-fueled ships, and the testing of methanol fuel cells. The potential of e-methanol, a carbon-neutral synthetic methanol, as a promising maritime fuel is also discussed. E-methanol is produced using renewable energy and carbon capture technologies, and it can blend with existing fuels without requiring significant modifications to vessels. The importance of using low-cost, biogenic carbon dioxide as a carbon source for e-methanol production, as well as the utilization of byproducts such as waste heat and dioxygen, is emphasized. Overall, the adoption of methanol and e-methanol as marine fuels can contribute to decarbonization efforts and reduce the carbon footprint of the maritime industry. [Extracted from the article]

The present study conceptualizes and simulates a methanol production process through the direct hydrogenation of captured CO2. CuO/ZnO/ZrO2 was employed as the catalyst and Aspen HYSYS was used for the process simulation. Configurational optimization of the process flowsheet was carried out using a step-by-step hierarchical approach. Many alternate flowsheets have resulted, and their capital investment, product cost, and profitability measures were calculated. The discrimination among the competing flowsheets was carried out based on net profit and percent return on investment. The retained flowsheet was further analyzed for optimizing the recycle ratio and evaluating the effect of the price of captured CO2, green H2, natural gas (fuel), and catalyst on the economic performance of the plant. The optimum value of the recycle ratio was computed to be 4.23. Additionally, it was found that the price of H2 is the most important parameter in defining the feasibility and profitability of the process. Mathematical correlations were also developed that relate the profitability and price of the above-mentioned feed materials. [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]

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]

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]

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]

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]