Preparation and characterization of Cu and Mn modified beta zeolite membrane catalysts for toluene combustion

Abstract

Cu and Mn as well as their mixed oxides modified beta zeolite membrane (Beta) coating on paper-like stainless steel fibers (PSSF) catalysts were successfully prepared and applied in toluene combustion. Firstly, Beta/PSSF with different crystallization temperature, crystallization time, Si/Al ratios etc. were prepared using secondary growth method, meanwhile, XRD, SEM and N2 adsorption-desorption isotherms were utilized to analyze the structures of the samples, respectively. Then, Cu and Mn as well as their mixed oxides loaded onto the obtained beta zeolite membrane with the optimal parameter were prepared by impregnating method. Finally, toluene combustion experiment was performed over a fixed-bed reactor. The experimental results depicted that continuous and well-intergrown beta zeolite membrane covered on the PSSF with typical truncated bipyramidal shape, and Beta/PSSF had a three-dimensional network with large void volume and majority of microporous. For the catalysts, the copper element existed as Cu2+ and Cu1+, and manganese element existed as Mn4+, Mn3+, and Mn2+. As a result, the catalytic activities for toluene combustion over mixed oxides as catalysts were superior to the single metal oxide catalysts. The T10, T50 and T90 of toluene combustion were dramatically decreased over Cu-Mn (1:3)- Beta/PSSF.