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Dimethyl carbonate (DMC) can be applied as a greener alternative to more hazardous materials, e.g. phosgene or dimethyl sulfate. Herein, one-pot synthesis of DMC from propylene oxide, methanol and CO2 using alkali halide catalysts under mild conditions was studied. Addition of Zn powder to the K2CO3-NaBr-ZnO catalyst system was seen to increase DMC selectivity from 19.8% (TOF = 39.0 h−1) to 40.2% (TOF = 78.1 h−1) at 20 bar and 160 °C for 5 h. Catalyst characterisation showed that Zn powder increases the stability of the catalyst, preventing the active ingredients on the catalyst surface from leaching. An increase in propylene oxide conversion to DMC is attributed to the increase of Zn2+ ions in the reaction solution. Elevated pressure was not found to be a necessary reaction condition for transesterification. This study shows that increased selectivity to DMC can be achieved at mild conditions with the addition of Zn powder.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '20 bar', 'Temperature': '160 °C', 'Catalyst': 'halide catalysts'}

In this work, intermetallic PdZn-ZnO catalysts supported on high surface area TiO2 were synthesized using metal-organic precursors and different Zn/Pd molar ratio (2.5, 5 and 7.5). The use of organic Pd and Zn precursors in the impregnation of TiO2 has made it possible to achieve the formation of PdO and ZnO nanoparticles that facilitate the uniform formation of small intermetallic β-PdZn particles after reduction with hydrogen at 450 °C. No significant differences in formation, crystallinity or size of intermetallic PdZn particles with varying the Zn concentration were observed. The differences were in the characteristics of the ZnO particles that lead to enhanced development of the contacts between the PdZn and ZnO particles . The best methanol yield (78.9 mmolMeOH·min−1·molPd −1) was obtained over the catalyst with highest ZnO content. This was consequence of the higher development of PdZn-ZnO interfaces, where CO2 adsorption and hydrogenation of intermediate species to methanol occurs, as well as of the higher stability of the largest ZnO particles under reaction conditions.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '30 bar', 'Temperature': '5 °C', 'Catalyst': 'TiO2 catalysts'}

Copper-zeolites have been reported to catalyze the direct conversion of methane to methanol. In this work, we report that pretreatment of copper-mordenite (Cu-MOR) using a gas mixture of NO and NH3 (NO/NH3) results in remarkably increased activity for the direct oxidation of methane to methanol. The methanol yield over the pretreated catalysts reaches as high as 106 μmol/gcat, compared to 28 μmol/gcat over the un-pretreated Cu-MOR. The NO/NH3 gas pretreatment redisperses CuO nanoparticles to Cu ions with catalytically favorable Cu oxidation state.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '40 bar', 'Temperature': '200 °C', 'Catalyst': 'pretreated catalysts'}

One of the methods of industrial dimethyl ether production is the catalytic dehydration of methanol. In this research work, methanol dehydration reactor has been modeled using continuous model and its results have been compared with experimental works and Voronoi pore network model. A 1D heterogeneous dispersed plug flow model was utilized to model an adiabatic fixed-bed reactor for the catalytic dehydration of methanol to dimethyl ether. The mass and heat transfer equations are numerically solved for the reactor. The concentration of the reactant and products and also the temperature varies along the reactor, therefore the effectiveness factor would also change in the reactor. We used the the effectiveness factor that was simulated according to the diffusion and reaction in the catalyst pellet as a Voronoi pore network model. Sensitivity analysis was performed to determine the influence of T, P and weight hourly space velocity on performance of the chemical reactor. Acceptable agreement was reached between the measured and the model data. The results showed that the maximum reaction conversion was obtained about 90 % at WHSV = 10 h−1 and T = 560 K, while the inlet temperature (Tinlet) had a greater effect on methanol conversion. In addition, the effect of water in the feed on methanol conversion was quantitatively studied. Also, the deactivation kinetics of γ-Al2O3 heterogeneous-acidic catalyst in methanol to dimethyl ether dehydration process was studied using integral analysis method. Based on independent deactivation kinetics, a second order was found that accurately fitted the experimental conversion time data. The main reaction activation energies and catalyst deactivation energies were 143.1 and −102.1 kJ/mol, respectively.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '1.46 bar', 'Temperature': '551 K', 'Catalyst': 'Al2O3 catalyst'}

Silica-supported silver nanoparticles exhibit outstanding efficiency in the CO2 hydrogenation to methyl formate in the presence of methanol under high pressure. Here, we show that ZrO2 and Al2O3 supports significantly increase the catalyst activity, in line with their higher Lewis acidity. The weight time yield of methyl formate over Ag/ZrO2 is up to 16.2 gMF gAg h−1 without detectable side-products, 25 times higher compared to Ag/SiO2 at the same temperature. Transient in situ and operando DRIFTS studies uncover spillover processes of formate species from Ag onto the acidic support materials and show that the surface formates can further react with adsorbed methanol at the sites near the perimeter between Ag and the support to yield methyl formate.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '300 bar', 'Temperature': '152 °C', 'Catalyst': 'Ag catalysts'}

Dedicated bioenergy combined with carbon capture and storage are important elements for the mitigation scenarios to limit the global temperature rise within 1.5 ° C . Thus, the productions of carbon-negative fuels and chemicals from biomass is a key for accelerating global decarbonisation. The conversion of biomass into syngas has a crucial role in the biomass-based decarbonisation routes. Syngas is an intermediate product for a variety of chemical syntheses to produce hydrogen, methanol, dimethyl ether, jet fuels, alkenes, etc. The use of biomass-derived syngas has also been seen as promising for the productions of carbon-negative metal products. This paper reviews several possible technologies for the production of syngas from biomass, especially related to the technological options and challenges of reforming processes. The scope of the review includes partial oxidation (POX), autothermal reforming (ATR), catalytic partial oxidation (CPO), catalytic steam reforming (CSR) and membrane reforming (MR). Special attention is given to the progress of CSR for biomass-derived vapours as it has gained significant interest in recent years. Heat demand and efficiency together with properties of the reformer catalyst were reviewed more deeply, in order to understand and propose solutions to the problems that arise by the reforming of biomass-derived vapours and that need to be addressed in order to implement the technology on a big scale.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '80 bar', 'Temperature': '3.2 °C', 'Catalyst': 'reformer catalyst'}

A potential measure to mitigate climate change and high energy consumption is the conversion of the abundant carbon dioxide (CO2) in industrial flue gas into value-added products. Herein, combined with the 300,000 tonnes of electrolytic manganese metal technical renovation project of Tianyuan Manganese Industry in Ningxia, the methanol production performed using 10,000 tonnes of CO2 annually is simulated. The hydrogen produced by alkaline hydro-electrolysis through solar and wind power generation is mixed with the CO2 purified in the manganese dioxide roasting workshop of the self-made manganese plant and fed into the methanol reactor with a Cu/Zn/Al/Zr catalyst. The methanol thus obtained is sold after separation and purification. The water at the bottom of the rectifying column is mixed with fresh water and circulated in the water electrolytic unit for hydrogen production. The design of the supporting photovoltaic (PV) power generation systems is simulated using TRNSYS18 software. Results show that the optimal reaction temperature, pressure and space velocity for methanol preparation using this system are 501 K, 50 bar and 5.9 m3/kgcat h, respectively. Simulation results indicate that the proposed methanol production process boasts a higher energy efficiency and process yield than the conventional process. Consequently, potential annual profits would increase by USD6.71 × 107 along with reduced greenhouse gas emissions. This study thus provides a novel approach for cogeneration of green methanol while reducing industrial waste gas emission.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '50 bar', 'Temperature': '501 K', 'Catalyst': 'Zr catalyst'}

The hydrogenation of CO2 to methanol is one of the promising CO2 utilization routes in the industry that can contribute to emissions mitigation. In this work, improved operating conditions were reported for the sustainable catalytic hydrogenation of CO2 to methanol using Cu/ZnO/Al2O3 catalyst operated at 70 bar and 210 °C. The CO2 feedstock used for this process is pure CO2 produced from the cryogenic upgrading process of biogas or hydrocarbon industries and ready-to-use hydrogen purchased at 30 bar and 25 °C. The process was modeled and simulated using the commercial Aspen Plus software to produce methanol with a purity greater than 99% at 1 bar and 25 °C. The simulation results revealed that an adiabatic reactor operated with a CO2/H2 ratio of 1:7 produces methanol with a yield ≥99.84% and a CO2 conversion of 95.66%. Optimizing the heat exchanger network (HEN) achieved energy savings of 63% and reduced total direct and indirect CO2 emissions by 97.8%. The proposed methanol process with an annual production rate of 2.34 kt/yr is economically sound with a payback period of nine years if the maximum H2 price remains below $0.97/kg. Hence, producing or purchasing gray H2 from a steam reforming plant is the most viable economic source for the process.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '150 bar', 'Temperature': '250 °C', 'Catalyst': 'Al2O3 catalyst'}

Photo-thermal reduction of atmospheric carbon dioxide into methane, methanol, and carbon monoxide under mild conditions over suitable (photo)catalysts is a feasible pathway for the production of fuels and platform chemicals with minimal involvement of fossil fuels. In this perspective, we showcase transition metal nanoparticles (Ni, Cu, and Ru) dispersed over oxide semiconductors and their ability to act as photo catalysts in reverse water gas shift reaction (RWGS), methane dry reforming, methanol synthesis, and Sabatier reactions. By using a combination of light and thermal energy for activation, reactions can be sustained at much lower temperatures compared to thermally driven reactions and light can be used to leverage reaction selectivity between methanol, methane, and CO. In addition to influencing the reaction mechanism and decreasing the apparent activation energies, accelerating reaction rates and boosting selectivity beyond thermodynamic limitations is possible. We also provide future directions for research to advance the current state of the art in photo-thermal CO2 conversion.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '100 bar', 'Temperature': '340 °C', 'Catalyst': 'semiconductor catalysts'}

The effect of adding Ag to CuO-ZrO2 catalysts for the hydrogenation of CO2 to methanol was investigated using CuO-ZrO2, Ag/CuO-ZrO2, and Ag/ZrO2. The addition of Ag to CuO-ZrO2 catalysts decreased the specific surface area and also broke its mesostructure. Thus, Ag played a significant role as a sintering aid in the preparation of Ag/CuO-ZrO2 catalysts. We note that the as-prepared Ag/CuO-ZrO2 catalysts contained Ag+ and Zr q + (q <4) sites and that the Zr q + content increased with increasing Ag+ content. Furthermore, the presence of CuO in the Ag/CuO-ZrO2 catalyst appeared to stabilize Ag+ and Zr q + species under air. Based on H2 chemisorption and powder X-ray diffraction patterns, formation of a Ag-Cu alloy was observed on completely reduced and spent Ag/CuO-ZrO2 catalysts. Completely reduced Ag/CuO-ZrO2 catalysts exhibited a higher methanol production rate (7.5mLh−1 gcat −1) compared to completely reduced CuO-ZrO2 (6.9mLh−1 gcat −1) and Ag/ZrO2 catalysts (2.2mLh−1 gcat −1) under the following reaction conditions: CO2/H2/N2 =1/3/1, catalyst loading=500mg, W/Ftotal =1000mgcat smL−1, reaction temperature=230°C, pressure=10bar.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '10 bar', 'Temperature': '230 °C', 'Catalyst': 'ZrO2 catalysts'}

Cu-ZnO-Al2O3 is the most widely applied catalyst for CO2 hydrogenation to methanol. However, it is still a challenge to produce methanol using this catalyst under low-temperature (<250 °C) and low-pressure (<10 bar) conditions with desirable yield and selectivity. In this work, by tuning the experimental processing parameters such as solvent, loading amount, and annealing temperature, highly improved ZnO nanoarray supported Cu-ZnO-Al2O3 catalysts have been successfully demonstrated. By using organic solvent (N,N-dimethylformamide (DMF), acetone, or isopropanol) for dip-coating loading process instead of deionized (DI) water, Cu-ZnO-Al2O3 nanocatalysts was comparatively better dispersed on the nanorod array support with populated and abundant active sites, thus enhancing the methanol yield. With the control of the loading amount and annealing temperature, finely distributed Cu nanoparticles were obtained on the ZnO nanorod surfaces to enhance the interactions between Cu and ZnO nanorod surfaces. Further improvement of the catalyst performance is demonstrated by tuning the reaction space velocity. At 200 °C and 10 bar conditions, the optimized catalyst achieved a methanol yield of 6.46 mol h−1 kg−1 with 100 % selectivity. The good stability after prolonged testing of the catalysts demonstrates the potential practical implementation. The in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) measurements under the 1 bar reveal that the CO2 hydrogenation to methanol on the ZnO nanoarray supported Cu-ZnO-Al2O3 catalyst follows the CO reaction pathway, due to the surface oxygen vacancies on ZnO nanorods which facilitate CO2 dissociation.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '10 bar', 'Temperature': '250 °C', 'Catalyst': 'Al2O3 catalyst'}

Microalgae are important biodiesel feedstocks because of their high lipid content and low land requirement for cultivation. One method of harvesting and concentrating algal biomass is by means of a foam column using surfactant CTAB as a collector and foaming agent, however, the downstream treatments for the “foamate” produced have not yet been investigated. Here, the freshwater microalgae strain, Chlorella vulgaris, was harvested by a continuous dispersed air flotation column and the foamate obtained was used as the feedstock for conversion to biodiesel via in situ reactive extraction using KOH as the catalyst. The process variables were methanol: oil molar ratio (100:1 to 1000:1), reaction temperature (40–60 °C) and reaction time (5–10 min). The maximum biodiesel yield from the foamate produced of 97% from C. vulgaris microalgae was accomplished at a molar ratio (methanol to oil) of 1000:1, a 60 °C temperature of reaction and a 10 min time of reaction. Longer reaction times resulted in reduced fatty acid methyl ester (FAME) yield due to saponification, converting the FAME to soap. High FAME yields were obtained despite the presence of significant quantities of free fatty acids (6% lipid) in the C. vulgaris biomass. The method also exhibited greater tolerance to water than that observed in conventional transesterification conditions. At a methanol: oil molar ratio of 1000:1, the method was not adversely affected by the presence of up to 80% level of moisture in the microalgae. Hence, a viable, FFA-tolerant, water-tolerant process has been demonstrated for direct conversion of microalgae foamate to biodiesel, at mild conditions (60 °C and below) in a short residence time (10 min).

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '0.48 bar', 'Temperature': '60 °C', 'Catalyst': 'base catalyst'}

The viability of catalyzed CO2 conversion routes strongly depends on improving the catalytic performance and understanding of the process. Herein, we investigate the effect of Ca loading on PdZn/CeO2 catalysts prepared using the sol–gel chelatization method for CO2 hydrogenation to methanol. A remarkable improvement in catalyst performance was revealed with the optimum amount of Ca (0.5 wt%) in synergetic cooperation with the PdZn alloy (main active phase for the CO2 hydrogenation to methanol reaction), compared to the Ca-free counterpart. The following key performance indicators are attained at 230 °C, 20 bar, and 2400 h−1 GHSV for the optimized catalyst: 16 % CO2 conversion, > 93 % methanol selectivity, and ∼ 124 g/kgcat/h methanol space–time yield. The overall catalytic performance observed is attributed to the optimum Ce3+/Ce4+ ratio, Ca2+ promotion, surface area, pore volume, and basic sites, as revealed by various characterization techniques. Results shown here indicate that the presence of Ca in the vicinity of the PdZn active enhances basicity, creates oxygen vacancies, and phase may have improved the spill-over ability of H2, consequently favoring CO2 activation and methanol formation.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '20 bar', 'Temperature': '1.5 °C', 'Catalyst': 'CeO2 catalyst'}

Catalytic hydrogenation of CO2 to methanol has gained considerable interest for its significant role in CO2 utilization using heterogeneous catalysts. This study is the first to propose a kinetic model based on Langmuir-Hinshelwood-Hougen-Watson (LHHW) mechanism for CO2 hydrogenation to methanol over a highly effective indium oxide (In2O3) catalyst. The work focuses on different reaction conditions mainly revolving around the variation of operating temperature, total reactor pressure, H2/CO2 molar feed ratio and weight hourly space velocity (WHSV) of the system. The experimental data were modeled using a competitive single-site kinetic model based on LHHW rate equations. A parameter optimization procedure was undertaken to determine the kinetic parameters of the developed rate equations. The model predicts that when the methanol synthesis reaction becomes equilibrium limited, the progress of the RWGS reaction forces the methanol yield to decrease due to the reversal of the methanol synthesis reaction. A mixture of CO2 and H2 has been used as the reactor feed in all the cases. Significantly w.r.t. the CO2 partial pressure, the reaction rate for methanol synthesis initially increased and then slightly decreased indicating a varying order. The single-site model accurately predicted the trends in the experimental data which would enable the development of reliable reactor and process designs.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '40 bar', 'Temperature': '200 °C', 'Catalyst': 'In2O3 catalyst'}

Direct conversion of CO2 via hydrogenation to value-added chemicals is a vital approach for utilising CO2 emitted into the atmosphere. In this paper, a critical analysis of reaction kinetic modelling studies is explored in a fixed bed reactor to improve methanol yield for different H2 to CO2 ratios by simulating a lab-scale reactor for adiabatic and isothermal conditions. The feed inlet temperature and pressure variations are applied to study the effect of both configurations on methanol production. The results show that the isothermal configuration yields 2.76% more methanol yield compared to the adiabatic reactor. The effect of H2 to CO2 molar ratios of 3, 6 and 9 on the performance of the catalyst and the influence of CO and CO2 hydrogenation is investigated with model simulations. The overall methanol yield is increased from 19.03% to 36.41% with increase in H2 to CO2 molar ratio from 3 to 9. Experiments are performed using commercial copper-based catalyst for different temperatures of 210, 230 and 250 oC at a pressure of 40bar for H2/CO2 of 3 and GHSV of 720h-1 as well as at optimal temperature of 250 oC and 50bar with varying H2/CO2 of 3, 6, 9 for 3g and 6g catalyst. The maximum methanol yield of 2.53% and space time yield of 13.59mg/gcat.h is obtained at H2/CO2 ratio of 9.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '40 bar', 'Temperature': '250 °C', 'Catalyst': 'CuZA catalyst'}

The method of Computational Fluid Dynamics is used to predict the process parameters and select the optimum operating regime of a methanol reformer for on-board production of hydrogen as fuel for a 3 kW High-Temperature Proton Exchange Membrane Fuel Cell power system. The analysis uses a three reactions kinetics model for methanol steam reforming, water gas shift and methanol decomposition reactions on Cu/ZnO/Al2O3 catalyst. Numerical simulations are performed at single channel level for a range of reformer operating temperatures and values of the molar flow rate of methanol per weight of catalyst at the reformer inlet. Two operating regimes of the fuel processor are selected which offer high methanol conversion rate and high hydrogen production while simultaneously result in a small reformer size and a reformate gas composition that can be tolerated by phosphoric acid-doped high temperature membrane electrode assemblies for proton exchange membrane fuel cells. Based on the results of the numerical simulations, the reactor is sized, and its design is optimized.

Extract the Pressure, Temperature, and Catalyst from the given input and provide them in a dictionary format with keys as "Pressure", "Temperature" and "Catalyst".

{'Pressure': '1 atm', 'Temperature': '180 °C', 'Catalyst': 'Al2O3 catalyst'}