【摘要】 红外法研究结果表明12-钨磷酸Fe³⁺、Mg²⁺和Na⁺盐都具有L酸点和B酸点。用Benesi法测得10种12-钨磷酸盐的酸强度顺序为(Al³⁺、Fe³⁺、La³⁺、Cu²⁺、Cd²⁺)>Zn²⁺>(Ca²⁺、Mg²⁺)>（Na⁺、Li⁺）,其酸量与抗衡阳离子的离子势和电负性大体成线性关系。还看出酸量与所含结晶水量有关。催化剂的酸量与其对异丙醇脱水反应和丁烯-1异构化反应的催化活性的关系表现出不同的特征,这可用“体相型”和“表面型”催化作用的不同特点来解释。更多还原

【Abstract】 IR study showed that the Fe3+, Mg2+ and Na+ salts of H3PW23O40 have both Lewis acid and Bronsted acid sites. The relative acid strength of salts of H3PW12O40 determined by Benesi’s method is roughly as follows.(Al3+, Fe3 + , La3+, Cu3 + , Cd3+)>Zn2+ >(Ca2+, Mg2 + )(Na+, Li+)The total acidity of H0≤+ 6.8 related approximately linearly with ionic potential and the electronegativity of the countercations. The acid quantity varied with the calcination temperatnre, showing maximum at 200-250℃.The somewhat different form of the graphs of catalytic activity versus acidity of catalysts on dehydration of isopropanol and isomerization of butene-1 might be due to that the former reaction occured in the bulk of the catalysts.更多还原