Influence of combined catalysts on the catalytic pyrolysis process of biomass: A systematic literature review

The need for energy resources is rising as a result of modernization and the industrial revolution, as well as fuel stocks are essential for security and sustainability. Research into alternative energy sources, which include solar cells and biofuels (biofuels, including biogas, bio-oil, and bio-char), is becoming more and more important as conventional fossil fuels run out. A thermochemical conversion process called pyrolysis can transform biomass into valuable compounds into bio-fuels. However, some issues such as thermal instability and excessive oxygen content require further processing. One of the fastest and most effective methods to use biomass is through pyrolysis. The selection of catalysts is a critical factor in the successful conversion of waste materials into valuable products by catalytic pyrolysis. During the pyrolysis process, catalysts can increase the calorific value of gaseous products and enhance the output and quality of significant products. Meanwhile, there are disadvantages to catalytic pyrolysis, including high hydrogen pressures and reaction temperatures, high operating costs, and catalyst deactivation. Several studies have been done to improve catalyst choices in order to increase the benefits and decrease the drawbacks of catalytic pyrolysis. By controlling product distribution and composition, altering reaction routes, and combining different catalyst types for synergistic effects, catalyst combinations can enhance catalytic performance. This systematic literature review aims to provide an overview of the impacts of combining catalysts and serve as a learning tool for future research on selecting catalyst combinations for biomass pyrolysis.