环保型增塑剂柠檬酸正丁酯的绿色合成工艺

围绕环保型增塑剂柠檬酸正丁酯传统合成工艺中存在的设备腐蚀性强、二次污染大、反应时间长等问题,分析反应过程中可能对产率影响的因素,通过对催化剂丝光沸石进行金属离子改性,进而探讨了微波协同改性丝光沸石高效催化合成柠檬酸正丁酯的绿色工艺条件。通过控制单因素实验,对多种金属离子改性丝光沸石的催化性能进行了比较,研究了无水柠檬酸与正丁醇物质的量之比(酸醇比)、改性催化剂的用量、微波辐照功率、微波辐照时间、反应温度等实验条件对柠檬酸正丁酯产率的影响,同时对催化剂进行了回收实验处理。结果表明,Al^3+改性后的丝光沸石具有较好的催化性能,是合成柠檬酸正丁酯时最适宜的催化剂,最适宜合成工艺为酸醇比1∶4、催化剂用量为无水柠檬酸质量的3%、微波辐照功率为500 W、辐照时间6 min、反应温度130℃,合成产物的产率可达91.7%,催化剂二次循环回收使用后合成产物的产率达87.4%。

Green Synthesis Process of Plasticizer Tri-n-Butyl Citrate

Aim at the problems of strong corrosion,large secondary pollution and long reaction time in the traditional synthesis process of eco-friendly plasticizer tri-n-butyl citrate,the factors that may affect the yield of tri-n-butyl citrate in the process of synthesis were analyzed.By modifying the catalyst mercerized zeolite with metallic ion,the green process synthesis conditions of tri-nbutyl citrate catalyzed by synergism of microwave and mercerized zeolite efficiently were discussed.Through control single variable method,the catalytic properties of various metal ion modified mercerized zeolites were compared,and the effects of molar ratio of anhydrous citric acid and n-butanol(acid alcohol ratio),modified catalyst content,microwave irradiation power,microwave irradiation time and reaction temperature on the yield of tri-n-butyl citrate were studied.Meanwhile,the recycle experiment of mercerized zeolite was done.The experimental results show that Al3+modified mercerized zeolite is the most suitable catalyst for synthesis of n-butyl citrate and has better catalytic performance,the most suitable synthesis process conditions are that acid alcohol ratio is 1∶4,modified catalyst content is 3% of mass of anhydrous citric acid,microwave irradiation power is 500 W,microwave irradiation time is 6 min,reaction temperature is 130℃,and the yield of tri-n-butyl citrate can reach 91.7%.After secondary recycling of catalyst,the yield of tri-n-butyl citrate is 87.4%.