In situ encapsulation of peroxophosphotungstate in ZIF-8: A highly active, reusable and structurally stable catalyst for desulfurization

Abstract

An efficient and sustainable catalyst is urgently needed for the actual oil refining process. Different amounts of peroxophosphotungstate (PW₄) were successfully encapsulated into the pore of ZIF-8 framework material to obtain composites (x%-PW₄@ZIF-8, x = 10.7, 14.6, 27.5 and 34.8) through a stirring process at room temperature for desulfurization of model diesel. The successful encapsulation of the active component PW₄ in the pore was verified by a variety of characterization methods, and there is weak force between the PW₄ and the ZIF-8. The composite 27.5%-PW₄@ZIF-8 showed good catalytic activity for various sulfides under moderate conditions. In addition, DBT removal rate catalyzed by 27.5%-PW₄@ZIF-8 could still reach levels of 95.1% after 10 cycles. The high efficiency of activity and excellent reusability are attributed to the high matching of host and guest sizes. This work provides new inspiration for designing and preparing catalysts with high activity and excellent reusability by a simple and environmentally friendly method.