采用两步法制备了功能化Brφnsted酸性双核咪唑离子液体催化剂,并用1H-NMR、FT-IR对催化剂的结构进行了表征,系统考察了其在醋酸与丁酯催化酯化高选择性地合成醋酸丁酯反应中的催化性能.结果表明,功能化Brφnsted酸性双核咪唑离子液体具有很好的催化活性,其催化活性与阴离子的种类有关,其中双-(3-甲基-1-咪唑)亚丁基双硫酸氢盐(MTEIMHS)的催化活性最好,在最佳催化剂用量为1.6%(wt),反应在90℃的温度下反应4 h,醋酸转化率可达到82%,且选择性接近99.9%.由此可见MTEIMHS双核离子液体有望成为一种有潜力的酯化催化剂.%A functional Brpnsted acid binuclear imidazole ionic liquid catalyst was synthesized by a two-step proceeding and its structure was characterized by 1H-NMR and FT-IR, respectively. The catalytic performance of the prepared ionic liquid catalyst used in the synthesizing butyl acetate by esterification of acetic acid and butyrate with high selectivity was systematically investigated. The results show that the prepared functional Brpnsted acid binuclear imidazole ionic liquid has perfect catalytic activity which is closely related to the kinds of active anions in it. It was found that the bis-(3-methyl-l-imidazole)butylidene double bisulfate (MTEIMHS)has the best catalytic activity, and under the optimal operation conditions found (catalyst used dosage 1.6 (wt),reaction temperature 90℃ and time 4 h), the conversion ratio of acetic acid can reach 82 and the selectivity is near up to 99.9 . It was confirmed that the MTEIMHS binuclear ionic liquid is expected to be a kind of potential catalyst for esterification.
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