关键词: 废塑料, 燃料, 热解, 催化剂, 反应机理

Abstract: Four types of processes of the waste plastic to fuel，included pyrolysis，catalytic cracking，pyrolysis followed by catalytic upgrading，and catalytic cracking followed by catalytic upgrading，were introduced and compared briefly. Recent advances in catalytic cracking catalysts of waste plastic and catalytic upgrading catalysts of cracking products were reviewed. The effects of catalyst acidity，specific surface area，pore diameter distribution and type of supported metal ions on catalytic cracking and upgrading reactions of waste plastics were analyzed. The thermal and catalytic cracking mechanisms of waste plastics of polyolefins and polystyrene were also described. Advices on research and development of the waste plastic to fuels were proposed. It was pointed out that the combination technology of catalytic cracking followed by catalytic upgrading would be the most promising process of waste plastic to fuel in the future，and its research should focus on the catalysts with the stronger acidity and appropriate porous structure，which could increase the reaction activities and diffusion rate of large molecules.

Key words: waste plastics, fuels, pyrolysis, catalyst, reaction mechanism