Beta@ZIF-67 复合材料的制备及对聚乳酸塑料的催化降解性能

Biodegradable plastics,such as polylactic acid(PLA),are preferable to traditional petroleum-based plastics. However,the natural degradation of PLA takes a long time and releases CO₂. Therefore,upcycling PLA is a better option for achieving sustainable development. In this study,a Beta@ZIF-67 composite was developed for efficient catalytic degradation of waste PLA plastics,which was achieved by growing the zeolitic imidazolate framework-67(ZIF-67) on the surface of Beta zeolite. As a result,the real-life PLA plastics were completely converted to methyl lactate in just 4 h at 180 ℃ with a yield up to 76.4%. The high catalytic efficiency was attributed to the composite's open pore structure,large specific surface area,and the synergistic effect of the active sites provided by ZIF-67(Lewis acid/base)and Beta zeolite(Brønsted acid). Overall,this study provides a new way for designing and synthesizing zeolite-based composite catalysts,which show promising applications in the catalytic degradation of plastics.