结晶水的性质及其对含钨杂多酸酸性的影响

CHARACTERIZATION OF CRYSTAL WATER IN HPA W AND ITS EFFECT ON ACIDITY OF HPA W CATALYSIS

在含结晶水较多的含钨杂多酸（ＨＰＡ－Ｗ·ｎＨ２Ｏ）中，结晶水有两种不同的存在状态。结晶水数ｎ不同的ＨＰＡ－Ｗ·ｎＨ２Ｏ，有不同的酸性表现。ｎ减小，酸性增强；当ｎ≈１时，表现最强的酸性；ｎ再减小，酸强度有所下降。另外，ｎ减小时，对酸强度高于－５．６的酸量分布产生影响，对酸强度低于＋３．３的酸量分布与总酸量基本没有影响。

There are two states of crystal water in HPA W·nH 2O.The n in the strongest acidity HPA W·nH 2O is not 0 but 1 although the acidity of HPA W·nH 2O is strengthened when n is decreased.As n decreases,the acid amount increases for HPA W·nH 2O with acid stronger than -5 6,but it is almost fixed for HPA W·nH 2O with acid strength less than +3 3.