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合成了ＨＰＷ１２、ＨＳｉＷ１２杂多酸的一系列铯盐：ＣｓｘＨ３－ｘＰＷ１２（ｘ＝０～３），ＣｓｘＨ４－ｘＳｉＷ１２（ｘ＝０～４）．测定了它们的酸强度、ｐＨ滴定曲线、ＮＨ３－ＴＰＤ、ＩＲ光谱和比表面积．以乙酸和正丁醇的酯化为探针反应，考察了催化剂的酸催化活性．实验发现，碱金属取代后，ＰＷ１２系列的多数催化剂的酸强度提高，而ＳｉＷ１２系列的则降低，但对同一系列来说，由ＮＨ３－ＴＰＤ测得的酸强度和酸量均随取代量增加而减小，ｐＨ滴定的结果与此类似，当ｘ＝２．５时，两系列催化剂的比表面积均存在一个极值．对乙酸和正丁醇的催化酯化活性只与总酸量有关，与表面积无关，属假液相反应．
A series of cesium salts of HPW12 and HSiW12 heteropolyacids were synthesized: CsxH3-xPW12 (x = 0 ~ 3) and CsxH4-xSiW12 (x = 0 ~ 4). Their acid strength, pH titration curve, NH3-TPD, IR spectra and specific surface area were measured. The esterification of acetic acid and n-butanol was used as the probe reaction, and the acid catalytic activity of the catalyst was investigated. It was found that the acid strength of most PW12 series catalysts was increased after alkali metal substitution, while that of SiW12 series was decreased, but for the same series the acid strength and acidity measured by NH3-TPD both increased with the substitution amount Similarly, the result of pH titration is the same. When x = 2.5, there is an extremum in the specific surface area of both series of catalysts. Acetic acid and n-butanol catalytic esterification activity only with the total acid content, has nothing to do with the surface area, is a pseudo-liquid phase reaction.