酸性离子液体催化丁烯酯化反应制备乙酸仲丁酯

Acidic Ionic Liquid Catalyzed Esterification of Butene for Preparation of Sec-butyl Acetate

采用两步法合成了[Bmim]HSO_4,[Bmim]Sb F6,Bmim]PF6,[BSmim]HSO_4,[BSmim]CF_3SO_3,[BSN222]H_2PW_12O_40,[Ph3PSO3H]HSO_4等离子液体,以离子液体及离子液体/酸性无机盐为催化剂,在90℃、混合碳四:乙酸体积比18:5、乙酸:催化剂摩尔比2、反应时间4 h条件下,催化丁烯与乙酸的酯化反应.结果表明,以[Ph_3PSO_3H]HSO_4为催化剂时,丁烯转化率、乙酸仲丁酯的选择性和收率分别达88.8%,100.0%和88.8%,远高于以浓H_2SO_4催化的转化率(73.5%)、选择性(77.7%)和收率(57.1%).以[Ph_3PSO_3H]HSO_4为催化剂的8次循环实验中,总丁烯转化率均大于88.4%,乙酸仲丁酯选择性均大于97.4%,且产物与离子液体易分离,催化效果和循环使用性能良好.

A series of acidic ionic liquids such as [Bmim]HSO4, [Bmim]Sb F6, Bmim]PF6, [BSmim]HSO4, [BSmim]CF3SO3, [BSN222]H2PW（12）O（40） and [Ph3PSO3H]HSO4 were synthesized following two-step method to substitute concentrated sulfuric acid as catalyst for esterification of butene. The synthesized ionic liquids and the blending with Lewis salts were used as catalysts for the esterification of butene with acetic acid at 90 ℃ for 4 h, under the volume ratio of the mixture of butane butene to acetic acid of 18：5, and the molar ratio of acetic acid to catalyst of 2. As [Ph3PSO3H]HSO4 was catalyst for the esterification of butene, the conversion rate of butene reached 88.8%, selectivity and yield of butyl acetate reached 100% and 88.8%, respectively, versus that values of sulfuric acid as catalyst of 73.5%, 77.7% and 57.1% under the same conditions. After 8 times re-use of [Ph3PSO3H]HSO4 as catalyst for the esterification of butene, the conversion rate of total butene keeps more than 88.4%, selectivity of butyl acetate more than 97.4%.