Preparations Of Solid Acid Catalysts And Their Catylitic Properties For Fries Rearrangement

In this thesis, the preparations and characterizations of a series of pillared layered and supported solid acid catalysts with porous structure were reported. All these materials have been applied to the catalytic reactions of Fries rearrangement of phenyl acetate. Two of them were proved to show the characteristic catalytic performances for the reaction.A series of pillared layered materials such as the mixed Al/Cr pillared -zirconium phosphate (Al/Cr-ZrP), zirconium sulphophosphnates, mixed Al/Cr pillared monmorillonite and heteropolyanions pillared hydrotalcites as well as the chromium pillared layered titanoniobate, have been prepared and characterized. The tetrahydrate zirconium sulfate supported on various support like silica gel. aluminum oxide, activated carbon and mesoporous materials have also been prepared and tested as the catalysts for the Fries rearrangement of phenyl acetate. The factors affect the properties of Al/Cr-ZrP during the preparation were investigated. It was found that the pillared product with precolloidalize by ethanolamine had a higher interlayer distance than that by n-propylamine. The relatively low concentrations (0.067M) and comparatively large amount (6.67CEC, cation exchange capacity) of cations are benefit for the increase of the interlayer distance of the final product. The mixed metal oxide pillared a -zirconium phosphate shows an interlayer distance higher than 3.96nm and a BET surface area about 310m2/g. Such a large surface area is mainllycontributed from the formation of the large amount of interlayer pores with a narrow pore size distribution at around 2.3nm by pillaring. The high selectivity for the disproportionate in cumene conversion reaction confirmed the formations of pores on Al/Cr-ZrP larger than those of Zeolites.It is found that the layered surface supported zirconium base solid catalyst showed a high catalytic activity and selectivity for the Fries rearrangement reaction. The catalyst showed a higher PA conversion activity and a much higher selectivity for o-hydroxyacetophenone (o-HAP) than strongly acidic zeolite catalysts. The favorite carrier materials and the optimum-loading amount of the active component were chosen. The catalytic properties of the catalyst were influenced significantly by the pretreatment temperatures. The characterization of the optimum catalyst showed that the high activity and selectivity of the catalyst resulted from the high degree of dispersion of the active component and moderate strong acidity as well as its large pore size.The reactions over (3 zeolite indicated that the ratio of Si/Al in zeolites might hardly affect the overall activity. However, the increase of the Al content is helpful for the increase of the selectivity of Fries rearrangement products. De aluminum of (3 zeolite affects the activity and selectivity obviously. The process of de aluminum decreases the amount of active acid site for Fries rearrangement. The overall activity of (3 zeolite was maintained when the zeolite structure was remained. On the other hand, the o-/p-HAP ratio was increased because of the decrease of crystallinity. The destruction of (3 zeolite by de aluminum led to the increase of the overall activity due to the formation byproducts.