Abstract:
The continuous growth of carbon dioxide (CO
2) emissions has led to the deterioration of the global environment, creating a serious crisis for the human living environment. As a major carbon emitter, the steel industry accounted for 16.9% of the total industrial CO
2 emissions in China. Thus, the steel industry shoulders significant responsibility for carbon reduction in the process of implementing the country’s dual carbon strategy. Converting CO
2 into high-value-added chemicals is an important way to achieve carbon reduction and resource recycling, but it faces certain technical challenges. The reverse water–gas shift (RWGS) reaction can convert CO
2 into syngas component carbon monoxide (CO), which has both thermodynamic feasibility and economic advantages. The produced CO can be used in the preparation of other industrial chemicals, which is a promising green route to fuel production. At present, the thermal catalytic process in the RWGS reaction is the main technical route. However, it has problems such as high thermodynamic stability of CO
2 and low CO
2 conversion rate, CO production, and energy efficiency. Thermodynamic analysis indicates that the temperature must be increased to maintain a high equilibrium CO
2 conversion rate. Reducing the temperature will lead to side reactions. The water produced by the reaction can also cause catalyst deactivation. Therefore, exploring various emerging enhancement technologies to solve the above problems is crucial for promoting the large-scale industrial application of RWGS reactions. Researchers have conducted extensive studies on the 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 enhancement RWGS reaction technologies. In this review, we first introduce the research progress of RWGS emerging enhancement technologies. The advantages and limitations of different RWGS technologies are compared, and the applications of membrane-, photothermal-, plasma-assisted, and electric field-promoted RWGS reaction and the improvement of reaction performance are discussed. Membranes have been widely used in other industrial reactions. In the RWGS reaction, water can be removed through membranes to achieve higher CO yields, which solves the problems of product separation and catalyst deactivation caused by H
2O. However, membranes are expensive and their performance degrades easily owing to contamination. The photothermal reaction harnesses the synergistic interplay between light and heat energies to initiate CO
2 reduction. This dual-energy approach transforms light into heat, effectively lowering the activation energy and overcoming energy barriers inherent in the RWGS reaction. Although this is an economical reaction route, the intermittency of sunlight and availability of high-performance photocatalysts remain a challenge. The synergistic effect of plasma-assisted and electric field-promoted systems with catalysts is conducive to improving the CO
2 conversion rate and suppressing side reactions. However, the above two technologies are still in the experimental research stage. Finally, the application prospects of RWGS emerging enhancement technologies and suggestions for further applications are discussed.