Metal Aluminum Phosphate Molecular Sieve Synthesis And Isomerization Performance

Isobutylene is the basic raw material for the production of MTBE, tert-butanol, methyl methacrylate, butyl rubber and other chemical products, the production of isobutene under the existing conditions of the letter to be addressed is the study of a high performance catalyst. This article by hydrothermal synthesis method, using phosphoric acid as the phosphorus source, intended boehmite as aluminum source diisopropylamine as a template, manganese acetate as the metal source, according to a certain proportion and order of mixing evenly, at a certain temperature as well as the conditions under autogenous pressure, through a certain time aging, successful synthesis of the load after the crystallization process of metal atoms MnAPO4-11molecular sieve. By XRD diffraction, SEM SEM, BET surface analysis, analytical tools NH3-TPD acid analysis, Fourier transform infrared spectroscopy were used to characterize molecular sieve, zeolite crystal grains of crystallinity, specific surface area, pore structure and acid strength and other factors a detailed study. After washing, drying, calcination, and molding the catalyst raw material mixture to C4, evaluated in a fixed bed reactor, the catalyst prepared by the reaction of n-butene isomerization reaction of isobutene in the performance. The results show that the hydrothermal synthesis, according to a certain proportion and order of the aluminum source, a phosphorus source, synthetic hetero atom molecular sieve having AEL structure, load metal hetero atoms MnAPO4-11zeolite framework with a weak acid, significantly improve the catalyst acid activity. Wherein n is the molar ratio of the compound. Optimal aging temperature is85℃-100℃, aging time of3to4hours, the crystallization temperature of190℃-200℃, crystallization time60h-72h. Through the micro-reactor the catalyst performance was evaluated at a space velocity of butene1.2h-1, the reaction temperature is300-380℃range, the reaction pressure is atmospheric pressure, the n-butene conversion was34%-60%of isobutene with yield reached36%, stable response performance.