Methanol Catalyst Research Articles

Synthesis and applications of highly stable silane modified reduced graphene oxide supported cobalt based platinum nanoparticle for anodic part of direct methanol fuel cells

In this study, the effects of silane on bimetallic nanoparticles modified with reduced graphene oxide were investigated for direct methanol fuel cells. In this direction, PtCo bimetallic nanoparticles were produced using the chemical reduction method. PtCo@NH2-rGO catalyst was obtained by combining these nanoparticles on 3-Aminopropyltriethoxysilane (APTES) modified reduced Graphene Oxide (rGO). Characterization of the PtCo@NH2-rGO catalyst was performed by X-Ray Diffractometry (XRD), Fourier Transform Infrared (FTIR), and UV–Visible Spectrophotometer (UV-VIS). The methanol oxidation performances of the obtained catalysts were investigated in order to observe the electrochemical effect of NH2-rGO supporting agent on unsupported PtCo and supported PtCo (PtCo@NH2-rGO) catalysts. The PtCo@NH2-rGO electrocatalyst showed a high oxidation peak current density (86.02 mA/cm2) for the anodic portion of the direct methanol fuel cell. This result shows the high performance of the NH2-rGO supported catalyst for direct methanol fuel cells. The resulting catalyst gives promise for potential direct fuel cell applications.

Utilization of marine ulva lactuca seaweed and freshwater azolla filiculoides macroalgae feedstocks toward biodiesel production: Kinetics, thermodynamics, and optimization studies

The current study compared between marine ulva lactuca seaweed and freshwater azolla filiculoides macroalgae to evaluate the productivity and characteristics of lipids and biodiesels. Using Soxhlet apparatus, 7.6 ± 0.10% and 12.52 ± 0.23% of lipids were extracted from ulva lactuca and azolla filiculoides, respectively. Besides, a second-order kinetic model and Eyring equations were used to conduct the study of kinetics and thermodynamics of oil extraction from both species. The activation energies were estimated to be 53.93 kJ/mol & 85.79 kJ/mol for ulva lactuca and azolla filiculoides, respectively. Analyses of thermodynamic properties of the Soxhlet extraction for both species revealed that the extraction was exothermal and temperature-dependent process. However, they are different in the Gibbs free energy of activation (ΔG) analysis where it revealed spontaneous extraction process for ulva lactuca and unspontaneous process for azolla filiculoides. The extracted oils from both species were subjected to optimized base-catalyzed transesterification in order to synthesize biodiesel fuel. Four independent varying variables were optimized using response surface methodology (RSM) which were oil to methanol molar ratio (1:3–1:12), NaOH catalyst ratio (1–2% w/w), temperature (55–70 °C), and time (1–2.5 h). The maximum biodiesel yield was from ulva lactuca lipids 88.77% obtained at 1:12, 1.5%, 63 °C, and 1.7 h. In contrast, 82.85% of biodiesel was yielded from azolla filiculoides lipids at optimal values 1:10, 1%, 60 °C, and 2 h for oil to methanol molar ratio, catalyst ratio, temperature, and time, respectively, for both species. Characteristics of both biodiesels revealed almost close compliance with ASTM D6751 and EN14214 standards. Apart from comparisons, it can be concluded that marine ulva lactuca seaweeds and freshwater azolla filiculoides macroalgae are obtainable, affordable, and potential feedstock toward sustainable biodiesel production.

Chemoselective Chan-Lam and reductive nitroarene coupling of boronic acid using an octahedral Ni-DMAP complex as catalyst

An octahedral Ni-DMAP complex has been developed as catalyst for C–N and C–S cross coupling and reductive nitroarene coupling using boronic acid as coupling partner. Reaction of amines, thiols, azides, and tosyl azides with boronic acids could be achieved in presence of 10 mol % of the catalyst in methanol at 80 °C without using extra base. The current protocol is highly selective for primary amines in presence of secondary amines, thiols and phenols. Reductive coupling of a range of nitroarenes and boronic acids was also successfully achieved using the same catalyst.

Application of Quasihexagonal Pt@PdS2-MWCNT catalyst with High Electrochemical Performance for Electro-Oxidation of Methanol, 2-Propanol, and Glycerol Alcohols For Fuel Cells

Today, it is very important to develop energy conversion devices such as fuel cells in order to meet the demand for clean energy. In fuel cells, on the other hand, nanostructures are frequently used. To benefit from this activity, the dendritic semi-hexagonal Pt@PdS2-MWCNT catalyst was synthesized using the hydrothermal method within the scope of the study. According to XRD results, it was determined that the crystal structure of Pt@PdS2-MWCNT was formed, and it had a crystal size of 4.11 nm. In addition, because of TEM studies, it was observed that there were particles of 4.02 nm on the MWCNT surface and a Quasihexagonal structure was obtained. The resulting catalyst was used in fuel cell application as an anodic catalyst for the oxidation of methanol, 2-propanol, and glycerol. The catalyst synthesized in the results obtained; Current peaks of 86.71 mA/cm2, 67.32 mA/cm2 and 58.44 mA/cm2 were obtained in cyclic voltammetry for methanol, 2-propanol, and glycerol, respectively. At the same time, scanning speed, chronoamperometry and long-term stability tests were performed for electro-oxidation stability and stability of the catalyst for methanol, 2-propanol and glycerol oxidations using sulfuric acid buffer solution. The results provided better stability and activity of the catalyst, with a higher current peak and 11.7% retention for methanol oxidation compared to other alcohols.

THE EFFECT OF Al2O3, CeO2, AND ZrO2 ON THE PERFORMANCE OF Cu/ZnO CATALYST IN METHANOL SYNTHESIS FROM BIOMASS PYROLYSIS SYNGAS

The effect of Al<sub>2</sub>O<sub>3</sub>, CeO<sub>2</sub>, and ZrO<sub>2</sub> as promoters on the catalytic activity of a Cu/ZnO catalyst for methanol synthesis from biomass pyrolysis syngas was investigated. The catalysts were prepared using a coprecipitation method, with the wt.% ratio of Cu:Zn:M = 68:28:4 (M = Al, Ce, and Zr). The activity of the catalysts was tested to determine the most appropriate promoter for the Cu/ZnO catalyst to accommodate methanol production from low stoichiometric number (S<sub>N</sub>) syngas. The experiment was performed in a continuous flow fixed bed reactor at 513 K, 4 MPa, gas hourly space velocity (GHSV) of 2000 h<sup>-1</sup>, and 24 h time on stream using simulated biomass pyrolysis syngas with a composition of 25% H<sub>2</sub>, 25% CO, 20% CH<sub>4</sub>, 20% CO<sub>2</sub>,10% N<sub>2</sub> (S<sub>N</sub> = 0.111). The effluent gas was analyzed every 6 h using gas chromatography to determine the conversion of gases and production of hydrocarbons. The catalysts were characterized by N<sub>2</sub> adsorption/desorption, Powder X-ray Diffraction (XRD), and Temperature Programmed Reduction of hydrogen (H<sub>2</sub>-TPR) techniques. It was found that the promoter in Cu/ZnO-based catalysts plays a crucial role in the methanol selectivity and catalysts stability, yet does not significantly affect feed conversion. Nevertheless, the findings will significantly contribute to developing a robust catalyst that can be used for a direct route for methanol production from biomass pyrolysis syngas.

Multifunctional ternary ZnMgFe LDH as an efficient adsorbent for ceftriaxone sodium and antimicrobial agent: sustainability of adsorption waste as a catalyst for methanol electro-oxidation.

In order to achieve sustainable benefits for the adsorption of wastewater pollutants, spent adsorbents need to be recycled and/or valorized. This work studied a two-dimensional (2D) ZnMgFe layered double hydroxide (LDH) for ceftriaxone sodium (CTX) adsorption. This LDH showed a crystallite size of 9.8 nm, a BET surface area of 367.59 m2 g-1, and a micro-sphere-like morphology. The factors investigated in this study were the adsorbent dose, initial concentration, initial pH, and contact time. ZnMgFe LDH showed 99% removal of CTX with a maximum adsorption capacity of 241.75 mg g-1 at pH = 5. The Dubinin-Radushkevich model was found to be the most adequate isotherm model. The spent adsorbent (ZnMgFe LDH/CTX) was reused as an electro-oxidation catalyst for direct methanol fuel cells. ZnMgFe LDH/CTX showed almost a 10-fold increase in electrochemical activity for all scan rates compared to bare ZnMgFe LDH in 1 M KOH. As methanol concentration increases, the maximum current density generated by both the ZnMgFe LDH and ZnMgFe LDH/CTX samples increases. Moreover, the maximum current density for ZnMgFe LDH/CTX was 47 mA cm-2 at a methanol concentration of 3 M. Both samples possess reasonable stability over a 3600 S time window with no significant deterioration of electrochemical performance. Moreover, the antimicrobial studies showed that ZnMgFe LDH had a significant antifungal (especially Aspergillus, Mucor, and Penicillium species) and antibacterial (with greater action against Gram-positive than negative) impact on several severe infectious diseases, including Aspergillus. This study paves the way for the reuse and valorization of selected adsorbents toward circular economy requirements.

Solid-state synthesis of Pt/C cathode catalysts for direct methanol fuel cells

In this study, we have used a facile and high-yield solid-state synthesis process to synthesize a highly dispersed and efficient Pt/C cathode catalyst for direct methanol fuel cell applications.

Tailoring the catalytically active sites in Co-based catalysts for electrochemical methanol upgrading to produce formate

Electrochemical valorization of bulk chemicals to produce value-added fine chemicals is highly attractive and deemed to be a green and economic way to optimize traditional industrial synthesis.

Modification of multi-walled carbon nanotubes with platinum-osmium to develop stable catalysts for direct methanol fuel cells.

In the study, a new bimetallic catalyst was synthesized for methanol oxidation using multi-walled carbon nanotube (MWCNT)-supported platinum-osmium (PtOs) nanoparticles (PtOs@MWCNT NPs). The morphological structures of the prepared NPs were examined using different techniques, such as scanning electron microscopy (SEM) and X-ray diffraction (XRD). The electrochemical characterization of the synthesized PtOs@MWCNT catalysts, such as chronoamperometry (CA), cyclic voltammetry (CV), scan rate (SR) analysis, cyclic catalytic test, and electrochemical surface area (ECSA) evaluation, were performed in an alkaline medium. From the results obtained, the size of the NPs was found to be 3.12 nm according to the Debye-Schrrer equation, and the MWCNTs were clearly observed by SEM imaging. After the characterization of the prepared nanomaterials, the PtOs@MWCNT catalysts were employed in the methanol oxidation reaction, and a high oxidation current value of 220.86 mA cm-2 was observed. Besides, according to the CA results, the catalyst exhibited high stability for 4000 s, and it was seen that Os metal improved the catalytic activity of the main catalyst. These results show that the PtOs@MWCNT catalyst is highly stable and reusable, and provides high electrocatalytic activity in the methanol oxidation reaction. Moreover, the obtained catalyst gave ideal results in terms of CO tolerance and activity. These data show that the obtained catalyst will provide significant improvement and superior efficiency in fuel-cell applications.

Metal organic framework-derived transition metal-doped CoSx nanocage for enhanced visible light-assisted methanol electrocatalytic oxidation.

Designing noble metal-free anode catalysts for visible light-assisted direct methanol fuel cells still remains a significant challenge. In this study, combining the photocatalytic and electrocatalytic properties of CoSx, a visible light-assisted methanol electrocatalytic oxidation strategy was provided. Doping engineering was employed to adjust the electronic structure of CoSx and improve their photoassisted methanol electrocatalytic oxidation activity. Using ZIF-67 as precursor, transition metal-doped CoSx (M-CoSx, M = Zn, Cu, Ni, and Cd) nanocage was synthesized by cation exchange and L-cysteine-controlled etching. Cd doping not only widens the light adsorption to the visible region but also enhances the separation efficiency of photogenerated electron-hole pairs. The electrochemical and photochemical results indicated that the strong oxidative photogenerated hole, OH˙, and O2˙- are beneficial for methanol electrocatalytic oxidation. The synergistic electrocatalytic and photocatalytic effect will be a practical strategy for improving the methanol electrocatalytic oxidation activity of noble metal-free semiconductor catalysts.

Effect of crystal size of ZSM-11 zeolite on the catalytic performance and reaction route in methanol to olefins

ZSM-11 zeolite is a promising catalyst for methanol to olefins (MTO); however, its low catalytic stability limits its realistic application. Herein, various ZSM-11 zeolites with different particle sizes were synthesized. The particle size of ZSM-11 has a significant influence on the formation and evolution of reaction intermediates, thereby determining its catalytic performance in MTO. Notably, S-ZSM-11, with a smaller particle size (approximately 400 nm), showed remarkable propene selectivity and catalytic lifetime as high as 42.6% and 243 h, respectively. These values were significantly higher than those observed with larger particle sizes (> 1 µm). The results obtained from gas chromatograph (GC)-MS, 13C MAS NMR, and various isotope-labeling experiments indicated that reduction of crystal size, accompanied by the generation of more intracrystalline mesopores, inhibits the aromatic intermediates formation and decreases the aromatic-based cycle contribution. In contrast, the alkene-based cycle is relatively enhanced, resulting in higher yields of propene and C3+ alkenes. Moreover, ethene is mainly produced via the paring route due to the limitation of alkyl side-chain growth of methylbenzenes.Highlights: various ZSM-11 zeolites with different particle sizes were synthesized by the hydrothermal method. S-ZSM-11, with a particle size of approximately 400 nm, shows superior catalytic performance in methanol to olefins. The propene selectivity and catalytic lifetime reach as high as 42.6% and 243 h, respectively. Decrease of crystal size inhibits the formation of aromatic species and decreases the aromatic-based cycle contribution. Ethene is mainly produced via the paring route.

Facile preparation of a methanol catalyst with ultra-high voltage efficiency and super-durability: Pt pollution introduction by composite electrodeposition

We innovatively develop a high-performance MOR catalyst with small amounts (3.2 wt%) of Pt by composite electrodeposition using a Pt plate as a counter electrode. The material exhibits ultra-high voltage efficiency and unparalleled stability.

Methanol Synthesis from CO2 and H2O Using a Solid Phosphate Electrolyzer at 240 °C and 28 Bar

It has been demonstrated that it is possible to produce methanol in one step in reasonable amounts by electrolysis of CO2 and H2O gasses dissolved under 28 bar and at 240 °C in contact with an electrolyte consisting of solid CsH2PO4 with additions of polyvinyl butyral (PVB) acting as a binder. The cathode was designed as a sandwich with a layer of a copper methanol catalyst and a porous platinum electrode. The anode consisted of porous ruthenium metal covered by a layer of RuO2. The system was operated with current densities of up to ca. 100 mA cm−2 with a voltage of less than 2 volts producing methanol with a Faradaic efficiency of up to ca. 7%. There seems to be nothing against recirculating the rest of reactant gases to improve the conversion. The question is of course whether the present approach can compete with a more traditional conversion starting with electrochemical produced hydrogen.

Extraction, Characterization and Determination of Physicochemical Properties of Biodiesel obtained from Desert Date (Balanites aegyptiaca) Seed Oil

Biodiesel is a domestically produced, clean-burning, renewable substitute for petroleum diesel. Using biodiesel as a vehicle fuel increases energy security, improves air quality and the environment, and provides safety benefits. . This study extracted, characterized and determined the physicochemical properties of biodiesel produced from Desert date (B. aegyptiaca) seed oil using Soxhlet extraction method with n-hexane as the extraction solvent. The oil obtained was characterized using FTIR and GC-MS analyses and its physicochemical properties determined. The oil obtained was subsequently transesterified using methanol and KOH catalyst. The obtained biodiesel was characterized and its physicochemical properties determined. The result showed that B. aegyptiaca seed oil had density of 0.9 g/cm3, viscosity of 6 cSt at 40 0C and viscosity of 2.5 cSt at 100 0C. The cloud and pour points of the oil was 21 and 9 0C respectively. The oil comprised of eleven fatty acids; predominantly linoleic acid (21.88 %), vaccenic acid (13.90 %) and palmitic acid (10.96 %). The biodiesel had density of 0.88 g/cm3, kinematic viscosity of 4.2 cSt, cloud and pour points of 16 0C and 7 0C respectively. The biodiesel also had free fatty acid (FFA) of 0.79 %, iodine value of 42 mgI2/100g and saponification value of 176. The biodiesel primarily consisted of 9,12-Octadecadienoic acid methyl ester (45.46 %), Hexadecanoic acid methyl ester (20.12 %), Butyl-9,12-Octadecadienoate (12.43 %) and Heptadecanoic acid-16-methyl ester (10.43 %). The properties obtained for the biodiesel were comparable to those of biodiesels reported in literature and thus, shows remarkable potentials to be used as substitute to fossil-based diesel fuel.

One-Pot direct reductive amination of furfural over Pd@CNTs

N-substituted furfuryl amines (secondary amines) are important class of organic compounds which are primarily used in making agricultural and pharmaceutical intermediates. The main objective of the present study is to develop the use of bio-based ennvironment friendly chemical such as furfural for selective one-step process for N-substituted furfuryl amines production using formic acid (FA) as a hydrogen source over heterogeneous catalyst. Rh-CNTs, Pd-CNTs, Pd-Al2O3, and Pd-HT catalysts were prepared using a facile combination of wet impregnation, followed by freeze-drying method and used for the synthesis of N-substituted furfuryl amines. The as-synthesized and used catalysts were characterized by various physico-chemical characterization methods to investigate the role of support in promoting activity and selectivity of catalyst. Under optimised condition, Pd-CNTs catalyst in methanol was found to convert furfural and aniline almost completely to N-(furan-2-ylmethyl)aniline. Moreover, Pd-CNTs catalyst showed outstanding activity towards complete decomposition of FA to H2 and CO2, giving a high yield of N-(furan-2-ylmethyl)aniline (>99%) from hydrogenation of furfural and aniline. The catalyst also showed good recyclability and worked for at least three consecutive recycling runs without lossing activity. The effect of reaction parameters viz. temperature, reaction time, and FA concentration, on the conversion and selecivity were studied in detail.

Investigation of Dual Fuel with Bipartite Additives in CI Engine

Extend the longevity of diesel in the world there is a need for identify ing alternatives sources. Biodiesel is the one of the best alternatives to overcome the fuel crises, day to day fuel price arise and environment emission concerns. In this study, the performance of the engine and emission has been studied. The raw non-edible waste cooking oil and Jatropha oils are equally blended 1:1 ratio is used to convert the biodiesel with methanol and alkaline catalyst KOH (Potassium Hydroxide) by transesterification process. Evaluated the physical properties of WJB value as per ASTM Standards. Nano additives magnesium oxide and graphene oxide were added 2:1 ratio mixed with biodiesel and diesel blend. The 4-stroke diesel engine used to find emission and performance of the bio-diesel blend WJB10, WJB20, WJB30,WJB40 and compared with mean diesel. The performance test ,combustion test and emission result were found lesser fuel consumption with brake thermal efficiency and reduced HC,CO,CO2 and NOx in WJB30 fuel blend compared to diesel.

DFT approach to the stability, the structural, electronic and photocatalytic properties of the ZnV2O6(001) surface terminations

The ZnV2O6 of (001) different surface terminations and the CO2 reduction process were examined using the first principles. We explored the several (001) surface terminations of ZnV2O6 and discovered that the surface terminated in O is the most stable. Although the light absorption coefficient of the surface terminated in Zn is significantly higher in the visible region than that of the surface terminated in O, and the work function is lower, the surface terminated in O has a preferable band gap (2.113 eV) for the photocatalytic reaction and the most stable surface energy. The adsorption and reduction mechanisms of CO2 on a ZnV2O6(001) terminated in O surface were examined, and the species tends to bind to O sites on the surface and form C–O or O–H bonds. CO2→COOH*→HCOOH*→HCO*→H2CO→CH2OH*→CH3OH is the best reaction pathway for CO2 reduction on surfaces terminated in O, and the hydrogenation of COOH* to HCOOH is the rate-determining step with a maximum ΔG and a 4.16 eV energy barrier. ZnV2O6(001) could be a decent candidate for a CO2 to methanol catalyst. As a conclusion, ZnV2O6(001) can be employed as a potential catalyst for converting carbon dioxide to methanol, and theoretical part of the ZnV2O6(001) interaction system has been expanded.

A non-corrosive bifunctional electrocatalyst based on titanate sheet for oxygen reduction and hydrogen evolution reactions

The development of suitable catalysts and catalyst supports is critical in the electrochemical energy generation methods. Herein, a titanate nanosheet-based catalyst support is synthesized and investigated for oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER). In an in situ single-step hydrothermal method, Pd nanoparticles were anchored onto sodium titanate nanosheet, which imparts excellent stability and methanol tolerance, suggesting its suitability as the cathode catalyst in direct methanol fuel cells. The electrocatalyst also demonstrated high efficiency towards electrochemical and photoelectrochemical hydrogen evolution reactions with an overpotential of −0.29 V and −0.20 V, respectively.

Application of Transesterification Derivatization Reaction for GC-MS Analysis

This paper is focused on study of the concentration of the basic catalyst in methanol on the yield of the derivatization transesterification reaction of triacyglycerols. Potassium hydroxide and sodium hydroxide solutions were used as basic catalysts. Triacylglycerols were transesterified, rapeseed oil was used as a sample. Triacylglycerols were converted to methyl esters of fatty acids, which were subsequently determined by GC-MS where the peak areas were monitored, because they represent the yield of the formed fatty acid methyl esters, namely palmitic, oleic, linoleic and stearic acids. The highest yield of transesterification of the oil to methylesters of fatty acids was found for a concentration of 3.0 mol dm–3 for KOH and 2.0 mol dm–3 for NaOH. At higher catalyst concentrations, a predominant side-reaction, saponification, was observed, which decreased the overall yield of fatty acid methyl esters.

Comparative study for electrochemical and Single-Cell performance of a novel MXene-Supported Platinum–Ruthenium catalyst for Direct methanol fuel cell application

• Novel formulation of bimetal embedded on MXene structure. • Latest two dimensional materials with ceramic and metal-like category. • Comparative study on electrochemical and DMFC single cell performance. • Promising anodic electrocatalyst for methanol oxidation reaction. • High electrochemical surface area and intrinsic activity leads to high performance. Direct methanol fuel cell (DMFC) is one of the reliable sources of energy owing to numerous benefits it offers and its suitability for portable electronic applications. Therefore, this study aims to overcome the main issues confronting anodic electrocatalyst part by introducing the novel formulation of platinum–ruthenium (PtRu) bimetal into the 2D Ti 3 C 2 T x structure to boost the electrocatalytic activity and single-cell performance. A comparative study for electrochemical measurement and DMFC performance is conducted between as-synthesized electrocatalyst PtRu/Ti 3 C 2 T x and two other electrocatalysts, PtRu/C and Pt/C. This comparative study between electrocatalyst revealed that PtRu/Ti 3 C 2 T x exhibits the highest electrochemical surface area (55 m 2 g -1 ), electrocatalytic and intrinsic activity (449 mA mg PtRu −1 / 1.36 mA cm ECSA −2 ), carbon monoxide tolerance (1.56), and smallest charge-transfer resistance (2.66 Ω) compared with other electrocatalysts. Furthermore, the validation by DMFC single-cell test showed that PtRu/Ti 3 C 2 T x electrocatalyst improves the performance almost 70 % compared to the Pt/C electrocatalyst. This excellent electrochemical and single-cell performance of PtRu/Ti 3 C 2 T x electrocatalyst validates its potential to be one of the promising candidates for the anodic electrocatalyst in DMFC application.