两种催化剂合成混合二元酸二甲酯的对比研究

The Contrast Research with Two Kinds of Catalysts for Catalytic Synthesis of Mixed Dimethyl Esters

以工业副产物混合二元酸(DBA)和甲醇为原料,分别用复合固体酸和PW12/Si O2为催化剂催化合成混合二元酸二甲酯(DBE),对比发现两种催化剂条件下的最佳合成条件均为甲醇和酸(DBA)摩尔比为3.5,催化剂的用量均为混合二元酸(DBA)质量的2%,反应时间均为4 h,载水剂加入量均为50 m L/100 g DBA,在此条件下,两种催化剂下的DBE收率均接近85%,产品酯的总质量分数均在98.6%以上,且两种催化剂重复使用5次时,DBE收率均大于70%,权衡利弊,在相同实验条件下,且DBE收率相似的条件下,使用固体酸催化剂加热催化酯化合成混合二元酸二甲酯具有较高的经济效益、环境效益和较好的应用前景。

With by-product of mixed dibasic acid（ DBA） and methanol as raw materials,using composite solid acid and PW12/ Si O2 as catalyst for the synthesis of mixed dimethyl esters（ DBE） respectively,it was found that two kinds of catalyst under the conditions had the similar synthesis conditions. The optimum conditions were as follows： the both mole ratio of methanol and acid（ DBA） was 3. 5,the dosage of the catalyst were mixed dibasic acid（ DBA） quality 2%,reaction time was 4 h,water carrying agent amount was 50 m L /100 g DBA. Under the above conditions,the yield of DBE two catalysts were close to 85%,the total mass fraction product ester were all above 98. 6%,and the two kinds of catalyst used repeatedly for 5 times,the yield of DBE was greater than 70%. Considering the advantages and disadvantages,under the same experimental conditions and the yield of DBE and similar conditions,the use of solid acid catalyst heating catalytic esterification of mixed dimethyl esters had higher economic benefits and environmental benefits and better application prospect.