废弃油脂脂肪酸甲酯制备二聚酸甲酯聚合工艺研究

Polymerization of waste oils fatty acid methyl esters to prepare dimer acid methyl esters

以废弃油脂制备的脂肪酸甲酯为原料进行聚合反应,产物经分子蒸馏后得到单体酸甲酯(生物柴油)和二聚酸甲酯。研究了催化剂加入量、反应温度和反应时间等因素对聚合反应产品收率和质量的影响。结果表明,聚合反应适宜的工艺条件为:催化剂加入量为脂肪酸甲酯质量的10%,反应温度240℃,反应时间8 h。在此条件下,二聚酸甲酯产率达到74.0%,粗产品经提纯后二聚酸甲酯含量为90.7%。自制片状活性白土催化剂活性好,催化剂与产品容易分离,产品夹带损失少。

Monomer acid methyl ester（biodiesel） and dimer acid methyl esters were coprepared by the method including polymerization of waste oils fatty acid methyl esters, and molecular distillation which divided the raw product of polymerization into biodiesel and dimer acid methyl esters. The effects of the amount of catalyst, reaction temperature and reaction time on the polymerization were studied. The results showed that the optimum conditions were as follows ： amount of catalyst 10% （ based on the weight of fatty acid methyl esters）, reaction temperature 240℃, reaction time 8 hours. Under the optimum conditions, the yield of dimer acid methyl esters was 74.0% , and their content was 90.7% after molecular distillation. The selfmade flake -shape activated bleaching earth was found to be an effective catalyst. It was easy to separate the catalyst from the product, thus the product loss was small.