| With increasing environmental awareness and demands on the process of economic development, a kind of catalyst, which both protects environment and improves economic efficiency, needs to be applied in the practically chemical industry. This kind of catalyst shows high activity, high selectivity, which allows the use of relatively small reactors and operation at mild conditions. Solid acid catalysts are the most widely used catalysts owing to their higher acid strength, thermal stability, lower reducibility, peculiar selectivity, catalytic activity, non-corrosive and environmentally benign and presenting fewer disposal problems. Their separation from liquid products is easier than the homogeneous catalysts. But most of solid acids still possess some disadvantages, for example, easy delution of active components, low mechanical strength, complexes surface property of the catalyst and intricate catalytic mechanism, which confine the catalysts to be widely used in the practical production. Particularly, the service life of catalysts is the important factors during they are used practically. How to study and tap catalysts of new type, higher benefits and longer service life become the hot topics. We select various supports and different active components to prepare several series of solid acid catalysts in order to measure the catalytic performance of catalysts and study the delution of active components on the supports. The preparation condition of complex catalyst APMB was studied. The catalysts were also used in amplifying reactions. All above provide a great number of referential data in the practical researches.A series of solid acid catalysts have been prepared by equilibrium and incipient wetness impregnation techniques and refluxing-adsorption techniques in the second part of this paper. By means of equilibrium impregnation technique, we have selected various supports and different active components to prepared several kinds of catalysts, such as TZ-1, a kind of NNNN, a kind of PW/DBTMn, and so on. These supports included montmorillonite, montmorillonite modified by surfactant, sepiolite, silicon oxide, and active carbon, the active components usually used heteroploy compounds or inorganic salts.The characterization of the catalysts was performed using X-ray powder diffraction (XRD), infrared spectroscopy (IR), thermal analysis 1 (DTA), and so on in the third part of this paper. The acid strength and the surface acid quantity of solid acid catalysts were measured though titration using n-butyl amine and different Hammett indicators. Based on these measurements, we researched the surface characters of supported catalysts and interaction between active components and their supports. Results show that active components were highly homodispersed on the supports, the strong interaction between them has also been proved. This character was also well displayed in the form of the stability of catalysts in the process of reaction.Different kinds of catalytic models were set up, such as esterification. acetal and ketal reaction, the catalytic properties, such as catalytic activity. selectivity, and stability were investigated. Results exhibited that catalysts have better stability, higher catalytic activity, longer catalyst life andhigher selectivity. Moreover, the selectivity of catalysts is near to 100 percent towards all the representative reactions selected. The catalyst of TZ-1 was used to esterification of acetic acid and alcohol, and the reaction demonstrated there is inverse ratio between delution of active components and catalytic properties, namely, the greater amount of delution of active components is, the lower of catalytic activity, stability and service life is. Among all catalysts, APMB displayed the highest catalytic activity and stability in the reaction of esterification. After it was used repeatedly ten times, the esterification rate still remained about percent 98. Through amplifying" experiment of imitative practically chemical industry, The catalyst's stability was still very hi...
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