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研究了12-钨磷酸及其14种盐以及其它3种Keggin型杂多酸对异丁烯齐聚反应的催化作用。发现12-钨磷酸的Fe(Ⅲ),La,Al,Cr(Ⅲ)和Cu(Ⅱ)盐对异丁烯齐聚反应有很高活性,可同12-鹤磷酸相媲美。各种12-钨磷酸盐的催化活性大体上随金属阳离子的电负性增大而增高,与盐的H_0≤+4.8的酸量也有相似的关联。齐聚生成物的聚合度主要与酸强度有关,酸强度越大,聚合度越高。杂多阴离子不一样的几种Keggin型杂多酸的催化活性次序与它们的酸性强弱次序相一致。
The catalytic effect of 12-tungstophosphoric acid and its 14 kinds of salts and the other three kinds of Keggin-type heteropolyacids on the oligomerization of isobutylene was studied. It was found that Fe (Ⅲ), La, Al, Cr (Ⅲ) and Cu (Ⅱ) salts of 12-tungstophosphoric acid have very high activity for the oligomerization of isobutene, which is comparable with that of 12- The catalytic activity of various 12-tungstophosphates generally increases as the electronegativity of the metal cation increases, similarly to the acid amount of H_0 ≦ + 4.8 of the salt. The degree of polymerization of the oligomerization product is mainly related to the acid strength, and the larger the acid strength, the higher the degree of polymerization. The order of catalytic activity of several Keggin-type heteropolyacids with different heteropolyanions is consistent with their order of acidity.