The role of catalysts in the decomposition of phenoxy compounds in coal: A density functional theory study.

The pyrolysis mechanisms of anisole (C 6 H 5 OCH 3 ), as a coal-based model compound, on CaO, ZnO and γ-Al 2 O 3 catalysts were studied using density functional theory (DFT). In contrast to the products of pyrolysis (C 6 H 6 , H 2 and CO), the products of catalytic pyrolysis on CaO, ZnO, and γ-Al 2 O 3 are C 6 H 5 OH and C 2 H 4 ; CO, C 5 H 6 and C 2 H 4 ; and C 6 H 5 OH and C 2 H 4 , respectively. Our results indicate that CaO, ZnO and γ-Al 2 O 3 catalysts not only decrease the energy barrier of C 6 H 5 OCH 3 decomposition but also alter the pyrolysis process and the products. It is also found that the pyrolysis gas H 2 alters the products on CaO (C 6 H 5 OH and CH 4 ), but it does not affect the products on ZnO and γ-Al 2 O 3 . In sum, these catalysts are beneficial for phenoxy compound decomposition. [ABSTRACT FROM AUTHOR]