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An electrocatalyst decorated with nickel oxide nanoflower and borophene (PdNiONF/B) has been presented as a possible catalyst for the ethanol oxidation reaction (EOR) in alkaline media. The crystal microstructure, composition, and morphology of the product were analyzed by using X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and Energy‐dispersive X‐ray spectroscopy (EDS). The catalytic activity of the PdNiONF/B for ethanol electrooxidation was assessed by using electrochemical impedance spectroscopy, cyclic voltammetry, and chronoamperometry. PdNiONF/B shows a high current at 0.12 mA as compared to palladium on carbon (Pd/C) and palladium on borophene (Pd/B) in 2 M of NaOH+ 2 M of EtOH. In addition, PdNiONF/B is stable and more tolerant of impurities. This observation suggests that PdNiONF/B possesses a better catalytic behavior. The ratio of the backward peak current (Ibwd) to the forward peak current (Ifwd) (Ibwd/Ifwd) in a 2 M of NaOH+2 M of EtOH is equal to (Ibwd/Ifwd) 1.0 V vs. Ag|AgCl for PdNiONF/B catalyst. This ratio indicates that PdNiONF/B has an excellent tolerance to ethanol intermediate species poisoning. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To develop environmentally friendly acetylene hydrochlorination catalysts with high efficiency to replace HgCl2, copper-based catalysts were prepared by the impregnation method. The catalyst with the best performance was finally obtained by adding organic additives NHP. The acetylene conversion rate of the catalyst reached 89%, and the test conditions were T = 150 °C, GHSV(C2H2) = 90 h−1, VHCl/VC2H2 = 1:1.08. The characterization results of XRD, TEM, and ICP showed that NHP improved the dispersion of Cu and reduced the loss of Cu. In addition, from the results of TPR and XPS, the NHP inhibited the reduction of Cuα+ to Cu0, thereby preserving the long-term stability of the catalyst. The BET and TGA results show that the addition of organic additives greatly suppressed the formation of carbon deposits during the catalyst reaction process. Overall, this research provided a series of high-performance Cu-based catalysts obtained by the addition of organic additives NHP. [ABSTRACT FROM AUTHOR]

Objective To develop the process of catalytic cracking of C4 olefins to propylene and the catalyst preparation technology, the pilot test and industrial side line test are completed. Methods The fixed-bed evaluation apparatus was used to investigate the impact of catalyst formulation, modification, and industrial conditions on catalyst activity, selectivity, and stability. Results The catalyst with ZSM-5 zeolite as the active component had good activity, selectivity, stability and regeneration performance in the conversion of C4 olefins to propylene. The introduction of phosphorus did not change the crystal structure of the catalyst, but it reduced the number of acidic sites on the catalyst, and adjusted the molar ratio of B acid and L acid of ZSM-5 zeolite. With the increase of phosphorus loading to 5wt * 0/0 the interaction between phosphorus and aluminum in molecular sieves was gradually strengthened, and phosphorus could interact with framework aluminum and non-framework aluminum. Conclusions The conversion rate of C4 olefins is more than 80%, the selectivity of propylene is 35% - 45% the once-through life of catalyst is more than one month, and the regeneration recovery rate is 95%. [ABSTRACT FROM AUTHOR]

Abstract An electrocatalyst decorated with nickel oxide nanoflower and borophene (PdNiONF/B) has been presented as a possible catalyst for the ethanol oxidation reaction (EOR) in alkaline media. The crystal microstructure, composition, and morphology of the product were analyzed by using X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and Energy‐dispersive X‐ray spectroscopy (EDS). The catalytic activity of the PdNiONF/B for ethanol electrooxidation was assessed by using electrochemical impedance spectroscopy, cyclic voltammetry, and chronoamperometry. PdNiONF/B shows a high current at 0.12 mA as compared to palladium on carbon (Pd/C) and palladium on borophene (Pd/B) in 2 M of NaOH+ 2 M of EtOH. In addition, PdNiONF/B is stable and more tolerant of impurities. This observation suggests that PdNiONF/B possesses a better catalytic behavior. The ratio of the backward peak current (Ibwd) to the forward peak current (Ifwd) (Ibwd/Ifwd) in a 2 M of NaOH+2 M of EtOH is equal to (Ibwd/Ifwd) 1.0 V vs. Ag|AgCl for PdNiONF/B catalyst. This ratio indicates that PdNiONF/B has an excellent tolerance to ethanol intermediate species poisoning.

To enhance the catalytic performance of nickel-based catalysts and improve their efficiency in biomass pyrolysis, a nickel-based catalyst supported on a ZnZr composite carrier was synthesized using the sol-gel method. The morphological changes of the catalyst before and after the reaction were observed using X-ray diffraction, scanning electron microscopy, nitrogen gas adsorption, temperature-programmed reduction, and other methods to analyze its catalytic performance. A series of experiments were conducted to explore the optimal conditions for the catalyst's gas production, including carrier material ratios, loading amounts, residence time, and reaction temperature. The bimetallic carrier of Zn and Zr provided a higher specific surface area, allowing the metallic nickel to enter its mesopores. The synergistic effect of the bimetallic system facilitated the catalytic activity of nickel, significantly enhancing gas production. The maximum CO and H2 production were achieved at Zn/Zr = 6/4. The catalyst achieved an optimal gas yield of 507 mL/g at a residence time of 20 min and a reaction temperature of 800 °C, demonstrating strong stability.

Copyright of Journal of the Chinese Society of Rare Earths is the property of Editorial Department of Journal of the Chinese Society of Rare Earths and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The catalyst activity monitoring in the selective catalytic reduction (SCR) system is of great importance for safety and economic operation in the power plant. To address the problem, a framework based on clustering considering time delay has been proposed. A compound parameter, q, is put forward in this paper as a strategy to remove the influences from gas volume (power output), inlet NOx concentration, and outlet NOx concentration to the ammonia amount. A modified entropy‐based fuzzy clustering (EFC) method is proposed by a threshold varying model and then tested for its efficiency by four datasets from the University of California, Irvine (UCI) machine learning repository. With the maximum mutual information entropy coefficient (MIC) method for detecting time delay and the modified EFC method, process data from three working levels are handled for automatically obtained clustering centres. The proposed activity value, μ, is then calculated based on 1440 process data before and after the catalyst replacement shown in boxplot figures. The results of the framework are analyzed to be in accordance with the real working conditions, with μ values and fluctuation ranges starting to fall near first from the 721st sample in the 24th box. [ABSTRACT FROM AUTHOR]

The activity of the Ni/diatomaceous earth catalyst used in the process of obtaining acetone from isopropyl alcohol was studied in a laboratory setup over a wide temperature range (150-350°C) at atmospheric pressure. The analysis of raw materials and reaction products was carried out by the chromatographic method. In the process of isopropyl alcohol conversion on the Ni/diatomaceous earth catalyst surface, the formation of compaction products and the effect of oxygen and hydrogen on the catalyst surface were studied using a Mag-Ben setup equipped with a quartz-spring reactor. The formation of compaction products on the surface of the Ni/diatomaceous earth catalyst was determined by thermogravimetric and kinetic methods. The maximum amount of compaction products is formed at a temperature of 300°C and above on the Lewis sites. Thermogravimetric studies showed that the formation of compaction product on the surface of the Ni/diatomaceous earth catalyst is time and temperature dependent. [ABSTRACT FROM AUTHOR]

Copyright of Materials & Technologies / Materiali in Tehnologije is the property of Institute of Metals & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A complex study of the structure, morphology, and electrochemical properties of the Pt20/SnO210/RGO electrocatalyst is presented. The advantage of the chemical synthesis of reduced graphene oxide (c-RGO) compared to thermal methods (t-RGO) is due to the formation of graphene plates with amorphous carbon black agglomerates and the chemical composition of the surface. The nature of the interaction between platinum and tin dioxide particles and a conclusion about the formation of heterostructures Pt-SnO2 with the surface interaction of lattices excluding the formation of hetero phases has been established. This achieves high dispersity during the formation of platinum particles without significant agglomeration and increases the electrochemical surface area (ESA) of platinum to 85 m2 g−1 vs. carbon black. In addition, the surface interaction of particles and the formation of hetero-clusters Pt-SnO2 can cause the improved activity and stability of the Pt20/SnO210/c-RGO electrocatalyst. [ABSTRACT FROM AUTHOR]

Hydrogen （H2 ), a renewable green energy source， has been widely focused on tackling environmental issues and fossil energy shortages. The development of low-cost， highly efficient and stable electrocatalysts towards hydrogen evolution reaction （HER） is one of the major challenges facing the large-scale utilization of hydrogen. Cobalt phosphide （CoP） has been widely studied in the field of electrocatalytic HER due to its metal-like properties and corrosion resistance in acid and alkali electrolytes. This review firstly elaborates the major advantages and challenges for CoP heterojunction as electrocatalyst for HER. Next， the different effects of the CoP heterojunction on HER are discussed. Finally， the prospects of CoP heterojunction for HER electrocatalysis are summarized and prospected. [ABSTRACT FROM AUTHOR]

This study investigated the effect of different Co3O4-based catalysts on the catalytic decomposition of nitrous oxide (N2O) and on nitric oxide (NO) conversion. The experiments were carried out using various reaction temperatures, alkaline solutions, pH, mixing conditions, aging times, space velocities, impregnation loads, and compounds. The results showed that Co3O4 catalysts prepared by precipitation methods have the highest catalytic activity and N2O conversion, even at low reaction temperatures, while the commercial nano and powder forms of Co3O4 (CS) have the lowest performance. The catalysts become inactive at temperatures below 400 °C, and their activity is strongly influenced by the mixing temperature. Samples without stirring during the aging process have higher catalytic activity than those with stirring, even at low reaction temperatures (200–300 °C). The catalytic activity of Co3O4 PM1 decreases with low W/F values and low reaction temperatures. Additionally, the catalyst's performance tends to increase with the reduction process. The study suggests that cobalt-oxide-based catalysts are effective in N2O catalytic decomposition and NO conversion. The findings may be useful in the design and optimization of catalytic systems for N2O and NO control. The results obtained provide important insights into the development of highly efficient, low-cost, and sustainable catalysts for environmental protection. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, we analyzed the durability of the commercial Pt/C catalysts with platinum loading of 20% and 40% using two different accelerated durability tests, i.e., using Ar or O2 when bubbling the electrolyte during testing. The structural analysis of the changes in the morphology of the catalysts was performed by XRD and TEM as well as the assessment of the degradation degree of the catalysts using the values of the specific surface area and ORR activity, both, before and after the stress testing. Regardless of the stress testing conditions, the JM20 material was established to degrade ESA and the catalytic activity to a greater extent than JM40, which may be due to the structural and morphological features of the catalysts and their evolution during the stress testing under various conditions. The JM20 material has been reported to exhibit a greater degree of degradation when bubbling the electrolyte with oxygen during the stress testing compared to argon, which may be explained by a different mechanism of degradation for the catalyst with the predominant oxidation of the carbon support, leading to a different nature of the distribution of the platinum nanoparticles over the surface of the carbon support, according to results that have estimated the number of nanoparticle intersections. [ABSTRACT FROM AUTHOR]

In the catalytic reforming process, aromatic yield is a standard for evaluating the production quality of the process, and studies are underway to improve productivity by optimizing the cost and energy. In particular, the activity and lifetime prediction of reforming catalysts can contribute to overall process efficiency improvement, such as product quality, productivity, and predictive maintenance. However, it is difficult to predict real-time catalyst activity and lifetime according to changes in process operation with the existing method that requires experimental data. In this study, a multiple linear regression (MLR) model and GRU model with the real process operating data are proposed for long-term plant operation and optimization in the counter-current continuous catalytic reforming. The MLR-GRU model predicts catalyst performance degradation and lifetime according to operating conditions by defining a new variable, reforming catalyst activity. The proposed model can predict the future reformate yield with an error of less than 1%. As a result of predicting the catalyst lifetime according to various operating temperatures, feed flow patterns, and feed quality, the feed flow rate had the greatest influence on the catalyst lifetime profile. In terms of the amount of produced reformate oil, the case with maximum feed rate is the worst (−25.6%); on the other hand, the case with minimum feed rate is the best (+11.4%). Thus, it is important to establish an appropriate production plan of the produced reformate oil. The model proposed in this study can predict the reformate yield and lifetime, reflecting the degradation of catalyst performance according to the operating profile in real-time, which is expected to improve productivity by production scheduling, optimization, and predictive maintenance. [ABSTRACT FROM AUTHOR]

A hydrothermal blending method was employed to successfully fabricate the SBA-16/α-MoO3 catalyst. In comparison with α-MoO3 and α-MoO3/SBA-16, SBA-16/α-MoO3 showed good catalytic activity in the conversion of synthetic diphenyl carbonate. At ambient pressure and a reaction temperature of 180 °C, the dimethyl carbonate (DMC) conversion reached 78.5% and the selectivity for diphenyl carbonate (DPC) was over 46.5%. The study was revealed that the SBA-16/α-MoO3 catalyst effectively regulated the Si distribution on surface of SBA-16, which was crucial to decrease the carbon deposition formation and increase the reaction rate. [ABSTRACT FROM AUTHOR]

A hydrothermal blending method was employed to successfully fabricate the SBA-16/α-MoO3 catalyst. In comparison with α-MoO3 and α-MoO3/SBA-16, SBA-16/α-MoO3 showed good catalytic activity in the conversion of synthetic diphenyl carbonate. At ambient pressure and a reaction temperature of 180 °C, the dimethyl carbonate (DMC) conversion reached 78.5% and the selectivity for diphenyl carbonate (DPC) was over 46.5%. The study was revealed that the SBA-16/α-MoO3 catalyst effectively regulated the Si distribution on surface of SBA-16, which was crucial to decrease the carbon deposition formation and increase the reaction rate. [ABSTRACT FROM AUTHOR]

Several biological properties of metal–organic frameworks (MOFs) and fiber compounds have been reported, and combinations of these structures can have unique properties. In this study, copper-containing and cobalt-containing MOF nanostructures were synthesized by the ultrasonic technique. Then, novel Cu/Co-hybrid MOF nanostructures were synthesized using the ultrasonic method. Synthesized Cu/Co-hybrid MOF nanostructures were used as a new and efficient recyclable catalyst in the synthesis of pyrano[2,3-c]pyrazole derivatives using the four-component reaction of phenylhydrazine, ethyl acetoacetate, malononitrile, and aldehyde. In the following, novel Cu/Co-hybrid MOF/PVA (poly vinyl alcohol) fiber nanostructures were synthesized by electrospinning and using Cu/Co-hybrid MOF nanostructures and PVA. The structures of the Cu/Co-hybrid MOF nanostructures and the Cu/Co-hybrid MOF/PVA fiber nanostructures were identified and confirmed using BET, TGA, FTIR, SEM, and XRD. In biological studies, the antibacterial, antifungal, and cytotoxicity activities of Cu/Co-hybrid MOF and Cu/Co-hybrid MOF/PVA fiber nanostructures were evaluated. In investigating the catalytic activity of Cu/Co-hybrid MOF, pyrano[2,3-c]pyrazole derivatives were synthesized with higher efficiency and less time than previously reported methods. High antibacterial (against gram-negative and gram-positive strains) and antifungal properties of synthesized Cu/Co-hybrid MOF nanostructures and Cu/Co-hybrid MOF/PVA fiber nanostructures were observed (MIC between 16 and 256 μg/mL), which were higher than some commercial drugs. In the investigation of cytotoxicity activity, the effectiveness on breast cancer cells was studied. The maximum cell proliferation and viability for Cu/Co-hybrid MOF and Cu/Co-hybrid MOF/PVA fiber nanostructures were 38% and 38% higher than the control in a concentration of 200 μg/mL after 48 h. The high catalytic and biological properties of the synthesized nanoparticles can be attributed to the presence of nano-sized bioactive metals and their high specific surface area. The significant physical-chemical properties obtained for synthesized nanoparticles in this study can be related to the desirable synthesis methods, the development of materials with high purity, and the incorporation of hybrid compounds into the nanostructures.

In this study, based on the new kinetic model, the novel configuration of the reactor in the acetylene hydrogenation process was proposed. The mathematical model is developed to evaluate the catalyst behavior in new configuration. Results indicated that the catalyst lifetime was increased near 50% by the change in the configuration of the bed reactor. The ethylene production flow rate was increased by 11 mol s−1. The consequent arrangement of the reactor beds, lead a delay in the catalyst regeneration step, about 200 days.

The present work quantifies metal-contaminant interactions between palladium substrates and three salient chlorinated organic contaminants, namely trichloroethylene 1,3,5-trichlorobenzene (TCB), and 3,3',4,4'-tetrachlorobiphenyl (PCB77). Given that Pd is one of the conventional catalytically active materials known for contaminant removal, maximizing catalytic efficiency through optimal adsorption dynamics reduces the cost of remediation of contaminants that are persistent water pollutants chronically affecting public health. Adsorption efficiency analyses from all-atom molecular dynamics (MD) simulations advance the understanding of reaction mechanisms available from density functional theory (DFT) calculations to an extractable feature scale that can fit the parametric design of supported metal catalytic systems and feed into high throughput catalyst selection. Data on residence time, site-specific adsorption, binding energies, packing geometries, orientation profiles, and the effect of adsorbate size show the anomalous behaviour of organic contaminant adsorption on the undercoordinated {110} surface as compared to the {111} and {100} surfaces. The intermolecular interaction within contaminants frommolecular dynamics simulation exhibits refreshing results than ordinary single molecule density functional theory calculation. Since complete adsorption and dechlorination is an essential step for chlorinated organic contaminant remediation pathways, the presented profiles provide essential information for designing efficient remediation systems through facet-controlled palladium nanoparticles. [ABSTRACT FROM AUTHOR]

H-Oil gas oils have a higher density and higher nitrogen content, and consequently much lower reactivity than straight-run vacuum gas oils during fluid catalytic cracking (FCC). The conversion of H-Oil gas oils observed in a laboratory catalytic cracking unit at constant operating conditions showed a 20 wt.% lower conversion rate than straight-run hydrotreated vacuum gas oil. Thus, a revamp of commercial FCC units, and the selection of a higher activity catalyst with lower coke selectivity is needed to provide the stable trouble-free operation of the unit. The performed revamp of the commercial FCC unit allowed a stable operation at a higher throughput. It also allowed an increased riser outlet temperature from 532 to 550 °C; increased maximum allowable regenerator temperature from 705 to 730 °C; decreased afterburning from 12 to 6 °C; decreased NOx emissions in the flue gas from 250 to 160 mg/Nm3; improved catalyst regeneration; decreased catalyst losses to 0.0142 kg/t feed; and improved catalyst circulation at a higher throughput. It was confirmed in the commercial FCC unit that the H-Oil light vacuum gas oil is the least reactive H-Oil gas oil during catalytic cracking. [ABSTRACT FROM AUTHOR]

This work focuses on the result of strontium doping on La 1−x Sr x Ni 0.8 Fe 0.2 O 3 catalytic cracking of coal tar in the COREX process. The results show that Sr doping significantly affected the catalytic performance of perovskite. O 2 -Temperature programmed desorption (O 2 -TPD) and X-ray photoelectron spectroscopy (XPS) results show that La 0.8 Sr 0.2 Ni 0.8 Fe 0.2 O 3 (Sr 0.2) has more active oxygen species and higher oxygen mobility. The performance of Sr-doped catalysts is higher than that of LaNi 0.8 Fe 0.2 O 3 , producing less tar and carbon deposition. Moreover, Sr 0.2 exhibited the highest gas yield of 34.6 mmol/g coal , H 2 yield of 27.5 mmol/g coal , 100% tar conversion rate, and the lowest carbon deposition of 19.4 mg/(g·h). Tar cracking mechanism was proposed by characterization results. The perovskite could serve as a bridge for oxygen migration and simultaneous oxygen supplementation, thus sustaining catalyst activity and durability. The appropriate amount of Sr doping perovskite is favorable to high catalytic activity and anti-carbon deposition at high temperatures. This work could provide some referential value for the highly-efficient cracking of tar. [ABSTRACT FROM AUTHOR]

The durability of low temperature proton exchange membrane fuel cell (PEMFC) catalysts crucially affects their lifetime. The choice of carbon support is important in terms of increasing the stability of catalysts. In this research, Pt/C samples were obtained using the polyol synthesis method on two types of carbon supports: the standard support, Vulcan XC-72, and carbon support with a high degree of graphitization, ECS-002402. One method for assessing structural characteristics is through transmission electron microscopy (TEM), according to which materials G1 and G2 showed an average nanoparticle size of 3.7 and 4.2 nm, respectively. On all catalysts, the oxygen reduction reaction proceeded according to the four electron mechanism. Durability was assessed by changes in ESA and activity in the ORR after 1000 cycles, with changes in the upper potential values: 0.7; 1.0; 1.2; and 1.4 V. After accelerated stress testing, the G1 material showed the greatest residual activity at a potential of 1.4 V (165 A/g (Pt). Based on the results of comparing various ADT protocols, the optimal mode of 0.4 and 1.4 V was chosen, and should be used for further studies comparing the durability of Pt/C catalysts. [ABSTRACT FROM AUTHOR]

Bed materials and their catalytic activity are two main parameters that affect the performance of the dual fluidized bed (DFB) gasification system in terms of product gas composition and tar levels. Two sources of bed materials were used for the operation of a commercial DFB gasification system in Thailand, using woodchips as a biomass feedstock. One source of the bed materials was the calcined olivine which had been used in the Gussing Plant, Austria, and the other activated bed material was a mixture of fresh Chinese olivine and used Austrian olivine with additives of biomass ash, calcium hydroxide and dolomite. These bed materials were collected and analysed for morphological and chemical composition using a scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray fluorescence spectroscopy (XRF). The product gas was cleaned in a scrubber to remove tars, from which the samples were collected for gravimetric tar analysis. Its composition data was automatically recorded at the operation site before it entered the gas engine. From the SEM, EDS and XRF analyses, calcium-rich layers around the bed materials were observed on the activated bed material. The inner layers of bed materials collected were homogeneous. Biomass ash, which was generally added to the bed materials, had significant calcium and potassium content. These calcium-rich layers of the bed materials, from the calcium hydroxide, biomass ash and dolomite, influenced system performance, which was determined by observing lower tar concentration and higher hydrogen concentration in the product gas. [ABSTRACT FROM AUTHOR]

A complex study of the structure, morphology, and electrochemical properties of the Pt20/SnO210/RGO electrocatalyst is presented. The advantage of the chemical synthesis of reduced graphene oxide (c-RGO) compared to thermal methods (t-RGO) is due to the formation of graphene plates with amorphous carbon black agglomerates and the chemical composition of the surface. The nature of the interaction between platinum and tin dioxide particles and a conclusion about the formation of heterostructures Pt-SnO2 with the surface interaction of lattices excluding the formation of hetero phases has been established. This achieves high dispersity during the formation of platinum particles without significant agglomeration and increases the electrochemical surface area (ESA) of platinum to 85 m2 g−1 vs. carbon black. In addition, the surface interaction of particles and the formation of hetero-clusters Pt-SnO2 can cause the improved activity and stability of the Pt20/SnO210/c-RGO electrocatalyst.

The catalyst MNi0.9Zr0.1O3 (M = La, Ce, and Cs) was prepared using the sol–gel preparation technique investigated for the dry reforming of methane reaction to examine activity, stability, and H2/CO ratio. The lanthanum in the catalyst LaNi0.9Zr0.1O3 was partially substituted for cerium and zirconium for yttrium to give La0.6Ce0.4Ni0.9Zr0.1−xYxO3 (x = 0.05, 0.07, and 0.09). The La0.6Ce0.4Ni0.9Zr0.1−xYxO3 catalyst's activity increases with an increase in yttrium loading. The activities of the yttrium-modified catalysts La0.6Ce0.4Ni0.9Zr0.03Y0.07O3 and La0.6Ce0.4Ni0.9Zr0.01Y0.09O3 are higher than the unmodified La0.6Ce0.4Ni0.9Zr0.1O3 catalyst, the latter having methane and carbon dioxide conversion values of 84% and 87%, respectively, and the former with methane and carbon dioxide conversion values of 86% and 90% for La0.6Ce0.4Ni0.9Zr0.03Y0.07O3 and 89% and 91% for La0.6Ce0.4Ni0.9Zr0.01Y0.09O3, respectively. The BET analysis depicted a low surface area of samples ranging from 2 to 9 m2/g. The XRD peaks confirmed the formation of a monoclinic phase of zirconium. The TPR showed that apparent reduction peaks occurred in moderate temperature regions. The TGA curve showed weight loss steps in the range 773 K–973 K, with CsNi0.9Zr0.1O3 carbon deposition being the most severe. The coke deposit on La0.6Ce0.4Ni0.9Zr0.1O3 after 7 h time on stream (TOS) was the lowest, with 20% weight loss. The amount of weight loss increases with a decrease in zirconium loading. [ABSTRACT FROM AUTHOR]

Methane Dry Reforming is one of the means of producing syngas. CeNi0.9Zr0.1O3 catalyst and its modification with yttrium were investigated for CO2 reforming of methane. The experiment was performed at 800 °C to examine the effect of yttrium loading on catalyst activity, stability, and H2/CO ratio. The catalyst activity increased with an increase in yttrium loading with CeNi0.9Zr0.01Y0.09O3 catalyst demonstrating the best activity with CH4 conversion >85% and CO2 conversion >90% while the stability increased with increases in zirconium loading. The specific surface area of samples ranged from 1–9 m2/g with a pore size of 12–29 nm. The samples all showed type IV isotherms. The XRD peaks confirmed the formation of a monoclinic phase of zirconium and the well-crystallized structure of the perovskite catalyst. The Temperature Program Reduction analysis (TPR) showed a peak at low-temperature region for the yttrium doped catalyst while the un-modified perovskite catalyst (CeNi0.9Zr0.1O3) showed a slight shift to a moderate temperature region in the TPR profile. The Thermogravimetric analysis (TGA) curve showed a weight loss step in the range of 500–700 °C, with CeNi0.9Zr0.1O3 having the least carbon with a weight loss of 20%. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering for Thermal Energy & Power / Reneng Dongli Gongcheng is the property of Journal of Engineering for Thermal Energy & Power and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Behavior of Pt/C catalysts obtained by the platinum deposition on standard and nitrogen-doped carbon supports with different microstructure has been studied in the oxygen electroreduction reaction in an acidic electrolyte. The catalysts based on the modified supports are characterized by a uniform spatial distribution of small-sized (1.5–2 nm) Pt nanoparticles over the surface of the supports, which results in high values of the electrochemically active surface area (110–130 m2 g− 1 (Pt)). The use of various stress testing protocols has shown that the Pt/C material based on the N-doped KetjenBlack EC DJ-600 possesses the highest mass activity and durability, which noticeably exceed the corresponding characteristics of the commercial HiSPEC3000 catalyst. [ABSTRACT FROM AUTHOR]

H-Oil gas oils have a higher density and higher nitrogen content, and consequently much lower reactivity than straight-run vacuum gas oils during fluid catalytic cracking (FCC). The conversion of H-Oil gas oils observed in a laboratory catalytic cracking unit at constant operating conditions showed a 20 wt.% lower conversion rate than straight-run hydrotreated vacuum gas oil. Thus, a revamp of commercial FCC units, and the selection of a higher activity catalyst with lower coke selectivity is needed to provide the stable trouble-free operation of the unit. The performed revamp of the commercial FCC unit allowed a stable operation at a higher throughput. It also allowed an increased riser outlet temperature from 532 to 550 °C; increased maximum allowable regenerator temperature from 705 to 730 °C; decreased afterburning from 12 to 6 °C; decreased NOx emissions in the flue gas from 250 to 160 mg/Nm3; improved catalyst regeneration; decreased catalyst losses to 0.0142 kg/t feed; and improved catalyst circulation at a higher throughput. It was confirmed in the commercial FCC unit that the H-Oil light vacuum gas oil is the least reactive H-Oil gas oil during catalytic cracking.

Magnetic oxide nanoparticles have engaged most consideration due to their rare character, such as easy separation, surface-tovolume ratio, paramagnetic and high surface area. Natural biopolymers, namely, (Chitosan, Guar-Gum, Tamarind, Alginate, Dextran, Pectin) have posed as an incredible host for the preparation of magnetic nanoparticles. Biopolymer based magnetic nanocomposites have been fabricated from long time using method like co-precipitations, green synthesis, in-situ, hydrothermal and wet chemical method. Properties of biopolymer magnetic nanocomposites draw attention to the researchers towards fabricating at the nano level for various applications like as adsorptions inorganic metal, organic impurity, targeted drug-delivery, bio-sensing, catalysis activity, antimicrobial activity, antifungal activity, antioxidant activity, anti-cancer activity, energy, environmental remediation, waste water treatment and textiles. This review is designed to report very firstly reported biopolymer magnetic nanoparticles (BMNPs) in last ten years and attractive approach in various applications. [ABSTRACT FROM AUTHOR]

Selective hydrogenation of acetylene was studied using palladium catalysts supported on different transition alumina spheres. The alumina supports were prepared by calcining pseudo boehmite alumina sphere at different calcination temperatures; the ρ-Al2O3 used was flash calcined alumina. The alumina supports were characterized using different techniques like XRD, surface area, pore volume and acidity. The Pd/Al2O3 catalyst were prepared, palladium penetration depth was measured using microscopic imaging and the catalyst reducibility were studied by Temperature Programmed Reduction (TPR). The microscopic imaging using TEM were done to study the palladium particle size and nature of particle clusters on the support surface. The catalyst performance evaluation was done in a fixed bed reactor with 1% acetylene in nitrogen feed and studied the impact of support properties on the catalytic activity. The catalyst prepared on γ-Al2O3 support showed the highest conversion and lowest selectivity, whereas the catalyst on α-Al2O3 support has the lower conversion and highest selectivity. Thermogravimetric analysis coupled with mass spectroscopy analysis were done for the spent catalyst to understand the possibilities of heavy component deposition of the catalyst. The catalyst prepared on α-Al2O3 support had the lowest hydrocarbon deposit on the surface whereas the γ and δ alumina showed the highest hydrocarbon deposits on the catalyst surface. [ABSTRACT FROM AUTHOR]

It is well known that hydrogen promotes catalyst activity in Cr/PNP‐catalyzed ethylene tetramerization, but the mechanism of this effect is unclear. A density functional theory (DFT) study was conducted to explore this effect, and conformation changes were carefully taken into consideration to build a clear reaction pathway. Three components in the ethylene tetramerization catalytic cycle were examined in detail: the production of 1‐hexene from metallacycloheptane, the production of 1‐octene from metallacyclononane, and the formation of an active centre on the Cr/PNP catalyst. This result indicates that the formation of an active centre on the catalyst becomes more favorable upon the imposition of hydrogen, where hydrogen functions as a second ligand. This easing effect could be the key factor leading to the outperformed Cr/PNP catalyst activity in ethylene tetramerization. [ABSTRACT FROM AUTHOR]

Volatilize different metals during the welding process of the cobalt supper alloy (Haynes 25) chambers and deposit on the catalyst can be negative effect on the catalyst life and activity. In addition, due to the exposure of the iridium catalyst to high temperatures, deactivation also effects on the catalyst's life time. In this work, we studied the deactivation effect with thermal degradation and by metal contamination of catalyst form plasma arc welding process of the cobalt based bed packed with iridium catalyst granules. The practical welding test was done to compare the catalytic activity of granules in the different places of bed along with an inert gas passing through the granules and cooling operation. The catalysts exposed to welding are characterized by EDX, XRD, and SEM. The catalytic decomposition properties are significantly destroyed after the welding test. The consideration of the catalyst surfaces proves that the precipitation of elements evaporated from cobalt-based alloy chamber, deteriorating the quality of the iridium catalytic activity. But liquid nitrogen used for cooling of weldment can be stabled the activity of catalyst exposed to hydrazine monohydrate. [ABSTRACT FROM AUTHOR]

Rechargeable Li–CO 2 battery is a facilitative and promising device for the conversion of CO 2 to electrochemical energy. However, it remains a challenge to enhance the sluggish decomposition kinetics of lithium carbonate as the discharge product. Herein, the Ru nanoparticles anchored on N-doped mesoporous hollow carbon nanospheres (Ru-AHCNs) are designed as cathode to enhance the electrochemical performance of Li–CO 2 battery. The Ru-AHCNs cathode displays a high discharge specific capacity of 11194.4 mA h g−1 at the current density of 100 mA g−1. In addition, the Ru-AHCNs cathode can stably run over 50 cycles and maintain a small overpotential (<1.38 V) with a limited capacity of 1000 mA h g−1 at 100 mA g−1. The excellent stability and catalytic activity of the cathode are ascribed to the following factors: (i) Uniform deposition of Ru nanoparticles in hollow carbon nanospheres can enhance the decomposition of Li 2 CO 3 and provide considerable exposure to active sites. (ii) N-doped mesoporous hollow carbon nanospheres can provide abundant electron transport channels and promote the nucleation of discharge products. These results evidently prove the reversible formation and decomposition of the discharge products, indicating that Ru-AHCNs cathode possesses excellent bifunctional catalytic activity. • Ru nanoparticles with considerable active sites can enhance Li 2 CO 3 decomposition. • N-doped mesoporous hollow carbon provides abundant electron transport channels. • Ru-AHCNs cathode delivers a small overpotential and high discharge capacity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe-based materials significantly improve the efficiency of microbial fuel cells. • Fe catalysts at cathode enhance ORR, favor 4e- pathway and reduce H 2 O 2 formation. • Regulating Fe and N dispersion enhances ORR activity and increases active sites. • Fe-N-C and FePc/CS catalysts outperformed commercial Pt/C in MPDs. • AI holds potential to improve Fe-MFCs by parameter and catalyst optimization. Microbial fuel cells (MFCs) face substantial challenges, including electrode cost, biofouling, and slow kinetics of the oxygen reduction reaction (ORR) at the cathode. This review examines iron-based (Fe-based) materials as electrodes and catalysts, emphasizing their efficacy in pollutant degradation and electricity generation. As anode modifiers, Fe-based materials enhance electrical energy production by improving electron transport, increasing anode voltage, and promoting microbial adhesion. At the cathode, they facilitate a more efficient 4-electron transfer process for the ORR, reducing undesirable hydrogen peroxide formation. This review discusses the impact of Fe and N dispersion, surface, and active site optimization on ORR activity and stability, highlighting the advantages of Fe-based materials in terms of stability, reproducibility, and biocompatibility through multi-element doping and nanoscale interface engineering. These modifications enable Fe-based materials to outperform traditional Pt/C catalysts in power density. The role of microbial communities, including Geobacter and Pseudomonas , in electron transfer and wastewater treatment in Fe-based MFCs is also addressed. Additionally, the potential of artificial intelligence (AI) to optimize operational and catalyst performance in enhancing Fe-based MFC efficiency is explored. This review concludes with a comprehensive assessment of Fe-based materials in MFCs, focusing on their contributions to sustainable energy and water purification by examining bioelectricity generation, fabrication costs, and power output, thereby providing a holistic overview of the advancement of Fe-based materials for environmentally sustainable applications. [ABSTRACT FROM AUTHOR]

To discuss the potential role of iridium (Ir) nanoparticles loaded under atmospheric and high pressures, we prepared a series of catalysts with the same active phase but different contents of 10wt%, 20wt%, and 30wt% on gamma-alumina for decomposition of hydrazine. Under atmospheric pressure, the performance of the catalyst was better when 30wt% of the Ir nanoparticles was used with chelating agent that had greater selectivity of approximately 27%. The increase in the reaction rate from 175 to 220 h−1 at higher Ir loading (30wt%) was due to a good dispersion of high-number active phases rather than an agglomeration surface. As a satisfactory result of this investigation at high pressure, Ir catalysts with different weight percentages showed the same stability against crushing and activity with a characteristic velocity of approximately 1300 m/s. [ABSTRACT FROM AUTHOR]

The performance of the commercial LUKOIL Neftohim Burgas fluid catalytic cracking unit (LNB FCCU) during processing 24 blends of straight run vacuum gas oils originating from 16 petroleum crudes and an imported atmospheric residue and employment of four catalysts was evaluated. It was found that the nature of the petroleum crudes processed in the ratios employed had no effect on the LNB FCCU performance. Instead, the content of the H-Oil vacuum gas oil (VGO) and its quality quantified by Kw-characterization factor was found to control the LNB FCCU conversion level. Based on the LNB FCCU commercial data a regression was developed quantifying the effect of equilibrium catalyst activity, H-Oil quality, and quantity in the fluid catalytic cracking (FCC) feed, and catalyst-to-oil ratio on the level of conversion. The regression was used to evaluate the impact of catalyst activity and catalyst-to-oil ratio, that is known to be a function of catalyst Δ coke selectivity, on the FCC conversion. [ABSTRACT FROM AUTHOR]

For the first time, silica gel-supported nickel hydrogenation catalyst has been synthesized via the mechanochemical method from oxides in a single stage. A set of data on the effect of the catalyst mechanochemical activation conditions on specific surface area, pore size distribution, crystallites size, and crystal lattice imperfection has been obtained. Activity of the obtained catalyst towards mild-conditions reduction of multiple carbon bonds in styrene, prop-2-en-1-ol, and diethyl maleate has been studied. Recommendations for establishing the optimal parameters for obtaining a nickel catalyst using mechanochemical synthesis have been elaborated. [ABSTRACT FROM AUTHOR]

Abstract Metal-incorporated SAPO-34 catalysts were prepared by one-step hydrothermal method. Effects of various parameters including the types of metal ions, Cu2+ sources, structure directing agents (SDAs), hydrothermal temperature and time on catalyst activity of the metal-incorporated SAPO-34 catalysts were investigated. Three types of metal-incorporated SAPO-34 catalysts (Cu/SAPO-34, Fe/SAPO-34 and Mn/SAPO-34) were successfully obtained. Compared with Fe/SAPO-34 and Mn/SAPO-34 catalysts, Cu/SAPO-34 catalyst revealed complete cubic-like microstructure, wide active temperature window and high conversion rate in selective catalytic reduction (SCR) of nitric oxide. After defined Cu2+ was the favorable active site of SAPO-34 catalyst, the effects of four Cu2+ sources on SCR performance were further investigated, and found Cu2+ sources did not produce significant influence on nitric oxide conversion rates. SDAs determined the formation of Cu/SAPO-34 catalyst, and the Cu/SAPO-34 catalyst adopting tetraethylenepentamine (TEPA) as SDA could maintain higher crystal integrity and active sites, which were in favor of the SCR reaction. Moreover, hydrothermal temperature and time had great influences on the formation of Cu/SAPO-34 catalyst. When the hydrothermal temperature was higher than 150 oC and the hydrothermal time was longer than 3 days, the Cu/SAPO-34 catalyst with a cubic-like structure and high catalyst activity could be obtained.

The effect of the quality of ebullated bed vacuum residue H‐Oil hydrocracking gas oils cracked in a commercial fluid catalytic cracking unit (FCCU) on its performance was studied. Six different catalysts were employed in this study. Four catalysts were tested in a commercial FCCU, and two in a laboratory FCCU. An increase of the H‐Oil hydrocracker reaction temperature was associated with a decrease in the KW factor of the H‐Oil gas oils. The diminished KW factor of H‐Oil gas oils resulted in lower FCCU conversion and higher regenerator temperatures. The FCC conversion at maximum gasoline yield is best predicted by the feed KW factor. The higher‐activity, higher‐Δcoke catalyst is unfavorable for FCCU performance because the excessive regenerator temperature excursions require reduction of the throughput. [ABSTRACT FROM AUTHOR]

Triphenylcarbenium ions (trityl cations: [RPh]3C+) are broadly identified organic compounds, because of their several uses, such as protective group, a catalyst for C–C bond formation, dye chemistry, carbohydrate chemistry, oxidation and reduction reagent, polymer and peptide synthesis, chiral catalyst, activity-based probes, and photochemical reactions. Trityl cations have also been applied as neutral Lewis acids in different chemical reactions. Possibly, the trityl cation is most widely used in hydride abstraction reactions both in the study of mechanisms transformations (organometallic and organic) and in organic syntheses. Ph3C+ is also extensively applied as very efficient activators and as one-electron oxidants for olefin polymerization reactions. In this review, we explain applications of trityl moieties in chemical processes and synthesis. [ABSTRACT FROM AUTHOR]

BACKGROUND The dry reforming of methane (DRM) process has received considerable attention for the production of syngas owing to its great environmental and economic benefits. LaNiO3 and La0.5Sr0.5NiO3 nanoparticles were synthesized with the co‐precipitation procedure using distilled and magnetic distilled water, and examined as catalysts in DRM. RESULTS: The structure and morphology of the prepared nanoparticles were characterized by X‐ray diffraction, the Brunauer–Emmett–Teller method, scanning and transmission electron microscopy, and temperature‐programmed reduction, desorption and hydrogenation techniques. The experimental results proved that the treated La0.5Ni0.5SrO3 catalyst had better initial performance in DRM in comparison with the LaNiO3 catalyst, due to its greater surface basicity. The orientation for deposition of carbon over the surface of the consumed catalysts was as follows: La0.5Sr0.5NiO3 treated > La0.5Sr0.5NiO3 non‐treated > LaNiO3 non‐treated > LaNiO3 treated. CONCLUSION: Among the synthesized catalysts, the treated La0.5Sr0.5NiO3 sample exhibited higher initial DRM activity, due to its greater surface basicity. Also, the higher surface basicity of the strontium‐substituted catalyst led to an increase in CO2 desorption and coke deposition according to the Boudouard reaction. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]