Abstract:
The continuous growth of CO2 emissions has led to the deterioration of global environment and a serious crisis to the human living environment. Converting CO2 into high-value-added chemicals is an important way to achieve carbon reduction and resource recycling, but currently still existing some technical challenges. The reverse water gas shift (RWGS) reaction has both thermodynamic feasibility and economic advantages, its produced CO can be further used in the preparation of other industrial chemicals, which was regarded as a highly potential and promising green route for fuel production. Researchers at home and abroad have conducted extensive studies on traditional thermal catalytic RWGS reaction in terms of catalytic material preparation, reaction mechanism analysis, and reaction parameter optimization. However, there is a lack of systematic review and evaluation of emerging RWGS reaction technologies. Comparing with thermocatalytic routes, the emerging technologies showed advantages in overcoming the problems of high thermodynamic stability of CO2, low CO conversion and CO production, and energy efficiency. In this review, we firstly introduce the research progress of RWGS emerging technologies, the advantages and limitations of different RWGS emerging technologies were compared, and the technologies application of membrane, photothermal, plasma-assisted and electric field-promoted in RWGS and the improvement of reaction performance were discussed. Membrane has been widely applied in other industrial reactions, in RWGS reaction, the water can be removed through membranes to achieve higher CO yields, which solve the problems of product separation and catalyst deactivation caused by H2O, but membrane are expensive and its performance degradation easily due to the contamination. Photothermal reaction harnesses the synergistic interplay between light and heat energies to initiate CO2 reduction, this dual-energy approach transforms light into heat, effectively lowering the activation energy, surmounting energy barriers inherent in the RWGS reaction, which is a economical reaction route, but intermittency of sunlight and the availability of high-performance photocatalysts remain the challenges currently faced. The synergistic effect of plasma-assisted and electric field-promoted systems with catalysts is conducive to improving the CO2 conversion rate and suppressing side reactions, but above two technologies are still in the experimental research stage. Then, the scale application challenges of RWGS emerging technologies were discussed. Finally, the application prospects of emerging technologies were prospected, and suggestions for further application were outlined.