Two Acid sites PEG thermoregulated ionic liquid was prepared and used as the catalyst for the esterification of aromatic acid and alcohol.The yield of esterification catalyzed by ionic liquid was 99% in 1 h at 80 ℃ w...Two Acid sites PEG thermoregulated ionic liquid was prepared and used as the catalyst for the esterification of aromatic acid and alcohol.The yield of esterification catalyzed by ionic liquid was 99% in 1 h at 80 ℃ with 0.1%(molar fraction)acidic PEG ionic liquid.The catalyst system could be applied to a wide range of esterification of aromatic acids and alcohols.The ionic liquid has the advantages of both homogeneous and heterogeneous phase at different temperature with a high product yield and the ease of product as well as catalyst separation.The ionic liquid studied plays the role of catalyst and is recycled up to seven times without any significant loss of activity.Morover,by simple phase separation the ionic liquid phase could be re-utilized up to seven times without leaching.展开更多
一步法制备了4种季铵盐型离子液体,并用FT-IR和1 H NMR表征结构。结果表明所合成的离子液体符合其理论结构;以它们为催化剂进行了乙酸正丁酯的合成研究,在相同条件下乙酸正丁酯的产率顺序为[Et2NH2][HSO4]>[Et3NH][HSO4]>[n-Pro3N...一步法制备了4种季铵盐型离子液体,并用FT-IR和1 H NMR表征结构。结果表明所合成的离子液体符合其理论结构;以它们为催化剂进行了乙酸正丁酯的合成研究,在相同条件下乙酸正丁酯的产率顺序为[Et2NH2][HSO4]>[Et3NH][HSO4]>[n-Pro3NH][HSO4]>[n-But3NH][HSO4],并且[Et2NH2][HSO4]和[Et3NH][HSO4]与产物不互溶,而[n-Pro3NH][HSO4]和[n-But3NH][HSO4]与产物互溶,表明季铵盐离子液体的催化活性和极性都随阳离子链长度的增加而降低。以三乙胺硫酸为催化剂考察了反应时间、反应温度、醇酸摩尔比和离子液体用量对乙酸正丁酯产率的影响规律,结果表明:在n(正丁醇)∶n(乙酸)∶n(离子液体)=1∶2∶0.25,反应时间8h,反应温度90℃的条件下乙酸正丁酯的产率达到81.94%。采用减压蒸馏,除去离子液体相中的水、乙酸正丁酯和未反应的原料,将离子液体进行循环使用4次,结果表明乙酸正丁酯的产率没有明显下降,说明离子液体的稳定性和循环使用性较好。展开更多
文摘Two Acid sites PEG thermoregulated ionic liquid was prepared and used as the catalyst for the esterification of aromatic acid and alcohol.The yield of esterification catalyzed by ionic liquid was 99% in 1 h at 80 ℃ with 0.1%(molar fraction)acidic PEG ionic liquid.The catalyst system could be applied to a wide range of esterification of aromatic acids and alcohols.The ionic liquid has the advantages of both homogeneous and heterogeneous phase at different temperature with a high product yield and the ease of product as well as catalyst separation.The ionic liquid studied plays the role of catalyst and is recycled up to seven times without any significant loss of activity.Morover,by simple phase separation the ionic liquid phase could be re-utilized up to seven times without leaching.
文摘一步法制备了4种季铵盐型离子液体,并用FT-IR和1 H NMR表征结构。结果表明所合成的离子液体符合其理论结构;以它们为催化剂进行了乙酸正丁酯的合成研究,在相同条件下乙酸正丁酯的产率顺序为[Et2NH2][HSO4]>[Et3NH][HSO4]>[n-Pro3NH][HSO4]>[n-But3NH][HSO4],并且[Et2NH2][HSO4]和[Et3NH][HSO4]与产物不互溶,而[n-Pro3NH][HSO4]和[n-But3NH][HSO4]与产物互溶,表明季铵盐离子液体的催化活性和极性都随阳离子链长度的增加而降低。以三乙胺硫酸为催化剂考察了反应时间、反应温度、醇酸摩尔比和离子液体用量对乙酸正丁酯产率的影响规律,结果表明:在n(正丁醇)∶n(乙酸)∶n(离子液体)=1∶2∶0.25,反应时间8h,反应温度90℃的条件下乙酸正丁酯的产率达到81.94%。采用减压蒸馏,除去离子液体相中的水、乙酸正丁酯和未反应的原料,将离子液体进行循环使用4次,结果表明乙酸正丁酯的产率没有明显下降,说明离子液体的稳定性和循环使用性较好。