Synthesis of dibutyl succinate catalyzed by magnetic solid superacid ZrO_2/SO_4~(2-)

Dibutyl succinate was synthesized from succinic acid and n -butyl alcohol using ZrO_2/SO_4~(2-)magnetic solid superacid as the catalyst. The influence of various factors on esterification percentage was inveatigated. The results showed that esterification percentage of over 91% was obtained under the optimum reaction condition, which was as follows: 0.05 mol succinic acid, n -butyl-alcohol-to-succinic-acid ratio = 2.4, quantity of catalyst = 0.5 g, quantity of water-carrying agent = 5 ml, reaction time 2 h. The catalyst could be easily separated from the product by magnetic separation.