Influence of pH of the solution on realumination of BEA zeolite

摘要

The influence of pH value in the solution on the realumination process of BEA zeolite wasrninvestigated by mean of nitrogen adsorption, XRD, ~(27)Al MAS NMR and FT-IR. It was foundrnthat non-framework aluminum species (octahedrally coordinated aluminums) in the solutionrnare easily reinserted into the framework of dealuminated BEA zeolite by controlling the pHrnvalue of the solution below 7. The cumene cracking activity of the realuminated BEA zeoliternat pH 5.1 was comparable to that of the parent BEA zeolite. The influence of aluminumrnspecies in the solution on the realumination process was also investigated using variousrnaluminum compounds.