Zhao Linlin, Shen Guoliang, Xu Tiejun, Wen Ruiyang, Jiang Sijin
School of Petrochemical Engineering, Shenyang University of Technology Liaoyang 111003 China
RSC Adv. 2025 Mar 4;15(9):6952-6961. doi: 10.1039/d4ra08443h. eCollection 2025 Feb 26.
Chelated titanium adipate with stable properties was prepared an ester-exchange reaction using low-carbon alkyl titanate, and it was characterized and analyzed using infrared spectroscopy, thermogravimetry, and scanning electron microscopy. Diisooctyl adipate (DOA) was synthesized an ester-exchange method using the synthesized novel titanium adipate as a catalyst and isooctanol and dimethyl adipate as raw materials, where dimethyl adipate is the methyl esterification product of the by-product (mixed dicarboxylic acid) in industrial adipic acid production. The process is easy to carry out, green and environmentally friendly, and the methanol by-product can be recycled and utilized. With the objective of optimizing the DOA ester exchange rate, the effects of three factors, namely, catalyst dosage, the molar ratio of isooctanol to dimethyl adipate and the reaction temperature at catalyst addition, on the optimization objective were systematically investigated one-way and response surface tests. Analysis of variance (ANOVA) and parameter optimization were conducted using Design-Expert software to obtain the optimal parameter combinations and verify the accuracy of the experimental results. The results showed that the optimal reaction conditions were as follows: a catalyst dosage of 2.39%, an isooctanol to dimethyl adipate molar ratio of 2.55 : 1, and a reaction temperature of 117 °C at the time of catalyst addition; this resulted in a high ester exchange rate of 94.23%. Due to the high catalytic efficiency, environmental friendliness and energy saving, and recyclable catalyst, this study provides a feasible process for the effective synthesis of DOA using industrial by-products, which is of significance.
采用低碳烷基钛酸酯通过酯交换反应制备了性能稳定的螯合钛己二酸酯，并利用红外光谱、热重分析和扫描电子显微镜对其进行了表征和分析。以合成的新型钛己二酸酯为催化剂，异辛醇和己二酸二甲酯为原料，通过酯交换法合成了己二酸二异辛酯（DOA），其中己二酸二甲酯是工业己二酸生产中副产物（混合二元羧酸）的甲酯化产物。该工艺易于实施，绿色环保，副产物甲醇可回收利用。为了优化DOA的酯交换率，通过单因素和响应面试验系统研究了催化剂用量、异辛醇与己二酸二甲酯的摩尔比以及添加催化剂时的反应温度这三个因素对优化目标的影响。使用Design-Expert软件进行方差分析（ANOVA）和参数优化，以获得最佳参数组合并验证实验结果的准确性。结果表明，最佳反应条件如下：催化剂用量为2.39%，异辛醇与己二酸二甲酯的摩尔比为2.55∶1，添加催化剂时的反应温度为117℃；此时酯交换率高达94.23%。由于该催化剂具有高催化效率、环境友好、节能且可回收等优点，本研究为利用工业副产物有效合成DOA提供了一种可行的工艺，具有重要意义。
