超声辅助提取美洲大蠊药渣残油及其制备生物柴油的研究

Ultrasonic-assisted Extraction of Residual Oil from Periplaneta americana Discards and Preparation of Biodiesel

为探索美洲大蠊药渣的综合利用的新途径,以美洲大蠊药渣为原料,石油醚为提取溶剂,通过正交设计优化超声辅助提取工艺条件,考察超声功率、提取时间、料液比和提取次数对残油提取率的影响。对制备的残油,进一步以硫酸作为催化剂,与甲醇进行酯交换反应制备生物柴油,通过正交设计优化制备工艺条件,考察反应温度、反应时间、油醇比和催化剂用量对转化率的影响。美洲大蠊药渣残油的最佳提取工艺条件为,超声波功率300 W、提取时间0.5 h、料液比1∶8、提取次数4次。在最佳提取工艺条件下,得油率可达24.25%。生物柴油的最佳制备工艺条件为:反应温度为65℃、反应时间2.5 h、油醇比为1∶5 mol/mol、催化剂用量为1.5%。转化率可达94.37%。

The purpose of this study was to explore the new way of comprehensive utilization of Periplaneta americana discards.With P.americana discards as raw material and petroleum ether as extraction solvent,the process conditions of ultrasonicassisted extraction of residual oil were optimized by orthogonal test.The effect of ultrasonic power,extraction duration,liquid to solid ratio and times of extraction on yield of residual oil were investigated.Furthermore,the oil was prepared using sulphuric acid as catalyzer through reaction of ester exchange with methanol,the preparation conditions were optimized through orthogonal experiment,and the effects of reaction temperature,reaction time,molar ratio of methanol to oil and catalyst amount on oil conversion rate were investigated.The results showed that the optimal extraction conditions of oil were obtained as follows：ultrasonic power of 300 W,extraction duration of 0.5 h,solid to liquid ratio of 1：8 and extracting for 4 times.Under the optimal extraction conditions,the yield of oil reached 24.25%.The optimal transesterification conditions were：reaction temperature of 65 ℃,reaction time of 2.5 h,molar ratio of oil to methanol of 1：6,catalyst amount 1.5% of oil weight.Under these conditions,the oil conversion rate was up to 94.37%.