CO2 conversion into methanol under ambient conditions using efficient nanocomposite photocatalyst/solar-energy materials in aqueous medium

CNT-based nanocomposite photocatalyst/solar-energy materials serving as in situ hydrogen generators for selective conversion [hydrogenation] of CO2 into methanol: a mechanistic/photoelectrochemical outlook.

Simulation of CO2 Conversion into Methanol in Fixed-bed Reactors: Comparison of Isothermal and Adiabatic Configurations

CO2 capture and utilization (CCU) has been widely considered as a potential solution to overcome global warming. Conversion of CO2 into methanol is an interesting option to transform waste into value-added chemical while also reducing greenhouse gases emissions in the atmosphere. In this paper, utilization of CO2 into methanol was simulated using Aspen Plus software. The reaction between CO2 and H2 to produce methanol and water was carried out in a simulated fixed-bed reactor with Cu/ZnO/Al2O3 commercial catalyst, following LHHW (Langmuir – Hinshelwood – Hougen – Watson) kinetic model. Isothermal and adiabatic reactor configurations were compared under similar feed conditions and the concentration profile along the reactor was observed. The result showed that isothermal configuration converted 3.23% more CO2 and provided 16.34% higher methanol yield compared to the adiabatic reactor. Feed inlet temperature variation was applied and the effect to methanol production on both configurations was studied. The highest methanol yield for adiabatic and isothermal reactor was obtained at 200 oC and 240 oC respectively.

Increase of the CO2 conversion into methanol by zeolite membrane technology using Cu-Zn-Al-Ce catalyst

The objective of this study is to increase CO2 conversion into methanol by applying zeolite membrane technology for reaction, using catalytic component with 16 % CeO2 -30 % CuO - 30 % ZnO/ 24 % Al2O3. Different experiments were conducted to identify the appropriate zeolite membrane to separate by-products. The following experiments determined the appropriate conditions for synthesis of methanol process from CO2 in reaction system with chosen zeolite membrane. The results of study showed that, NaA membrane could separate water out of the gas mixture after reaction the most effectively. This will limit the influence of water by-product on the catalytic activity and produce larger methanol amount in comparison to the reaction system without zeolite membrane. NaA zeolite membrane has shown its good performance since the produced methanol is 1.4 to 1.7 times higher than of non-membrane reaction system. The optimal conditions for methanol synthesis reaction from CO2 using the NaA zeolite membrane are: temperature from 220 to 240 oC, pressure is 5 bar, flow of materials input is 200 ml/min, the ratio of H2:CO2 is 3:1. Potential applications of the methanol synthesis from CO2 using zeolite membrane reactor system is absolutely suitable.