Catalytic strategies for CO2 hydrogenation to BTX and p-xylene: A sustainable approach towards carbon neutrality

In recent decades, the substantial rise in atmospheric carbon dioxide (CO2) levels has raised significant environmental concerns, such as global warming and ocean acidification. As a result, reducing carbon emissions and the interest in carbon neutrality have emerged as vital global goals to protect the environment and society. The hydrogenation of CO2 to produce BTX (benzene, toluene, xylene), particularly p-xylene (PX), provides a sustainable pathway for CO2 transformation toward valuable chemical feedstocks. This review presents an overview of the thermodynamics and reaction mechanisms involved in CO2 hydrogenation to BTX and PX, revealing the key factors influencing product selectivity. The effects of catalyst modification methods, including silylation, silicalite encapsulation, core-shell structures, and metal modification, on the selectivity and activity of catalyst are discussed. Factors such as zeolite morphology, catalyst size, contact time, mesoporosity, acidity, and surface alkylation/methylation are analyzed for their effects on BTX and PX selectivity. Lastly, the paper outlines the current challenges and future perspectives in advancing CO2 hydrogenation towards the production of BTX and PX, highlighting opportunities for further research and technological advancements in this area.