咪唑类离子液体催化合成抗氧剂BHT

2，6-二叔丁基对甲酚（BHT）是一种受阻酚类抗氧化剂，因其抗氧化性强、挥发性低、稳定性高、耐用性好等优点被广泛应用于化工、食品、医药等领域。本文以对甲酚和异丁烯为原料，对咪唑类离子液体1-（3-磺酸基丙基）-3-甲基咪唑（IL1）催化合成BHT的反应进行了研究，得到的最优反应条件为：对甲酚与催化剂IL1的摩尔比为5：1，在80℃下反应8h。BHT粗品的含量达到99.1%，收率为93.0%，且IL1重复使用4次后仍具有较高的催化活性。与传统酸性催化剂如浓硫酸和对甲苯磺酸比较，IL1具有催化活性高、易于分离、可重复使用、对设备腐蚀性小等优点，在BHT的工业制备中具有良好的应用前景。

Study on the synthesis of BHT catalyzed by ionic liquid

As a typical sterically hindered phenolic antioxidant,2,6-di-tert-butyl-4-methyl-phenol,also known as BHT,is widely used in chemical industry,food,medicine and other fields owing to its strong anti-oxidation property,low volatility,high stability and strong durability.The preparation of BHT catalyzed by 1-(3-sulfopropyl)-3-methyl imidazole(IL1) using p-cresol and isobutylene as the starting materials was studied.The optimal reaction conditions were determined as follows:the molar ratio of p-cresol to IL1 was 5:1,and the reaction was carried out at 80℃ for 8h.The purity of crude BHT was 99.1% and the yield was 93.0%.Furthermore,it was found that IL1 could be recycled for at least four times without any apparent loss of catalytic activity.In general,IL1 was a promising alternative for such traditional acid catalysts as H₂SO₄ and TsOH for the preparation of BHT,owing to its advantages of easy separation,reusability,high activity,and low corrosion to equipment.