纳米SO_4^(2-)/Sm_2O_3催化合成乙酸异戊酯的研究

Study on synthesis of iso-amylacetate utilizing SO_4^(2-)/Sm_2O_3 as catalyst

针对传统的乙酸异戊酯生产主要以浓H2SO4做催化剂,具有选择性低、设备易腐蚀、产品易碳化及环境污染严重等缺点,利用自蔓延低温燃烧技术成功开发了一种纳米固体超强酸SO24-/Sm2O3催化剂.考察了该催化剂对乙酸与异戊醇反应制备乙酸异戊酯的催化活性,并与浓H2SO4、非纳米级SO42-/Sm2O3固体超强酸进行了比较.结果表明,纳米级固体超强酸对该酯化反应具有良好的催化活性,且具有无污染、无腐蚀,可以循环利用等优点.实验研究表明,当n(乙酸)∶n(异戊酯)=1∶4,催化剂用量为0.25g,反应时间为2h,反应温度为110℃,其酯化率高达96%以上.

Iso-amylacetate has been widely applied in chemical engineering. food and dope fields use it as a kind of important chemical engineering material and food additive. Concentrated H2SO4 is usually utilized as a catalyst for traditional production process of iso-amylacetate, which has some mortal bugs such as low selectivity, likely production carbonization and serious environmental pollution. In this present paper, a nanosolid superacid /Sm2O3 had been successfully prepared by auto-combustion low temperature synthesis technique, and its catalytic activity for the esterification reaction of isoamyl alcohol and acetic acid was investigated in detail. A comparison of nanosolid superacid with concentrated H2SO4 and conventionally synthesized non-nanometric superacid /Sm2O3 indicates that the newly-synthesized product has a higher catalytic activity for the esterification reaction, besides higher stability and no pollution. It was also found that when molar ratio of acetic acid and isoamyl alcohol was 1∶1.4, addition amount of the catalyst was 0.25 g, reaction time time was 2 hours and reaction temperature was kept at 110 ℃, efficiency of the esterification exceeded 96%. Thus the nanosolid superacid, as a sort of higher effective and cheaper catalyst, will be able to replace traditional one for esterification and be used in industrial production.