The primary goal of this study is to develop a composite material from the anthill and chicken eggshell and to use it as a catalyst for the synthesis of biodiesel from virgin and waste vegetable oils. The anthill–eggshell composite (AEC) catalyst was prepared using an incipient wetness impregnation method. Central composite design (CCD) was applied to investigate the effects of catalyst preparation parameters (calcination temperature, calcination time, and anthill proportion in the AEC) on the yields of biodiesel from the two oils. Based on the CCD, two quadratic models were developed to correlate the AEC preparation parameters to the two responses. Analysis of variance (ANOVA) was performed to verify the reliability of the models and also, identify the factor that mostly affects the experimental design responses. Optimization results showed that the predicted values of biodiesel yield from the models for the two oils agreed reasonably well with the experimental values. The optimum conditions for the preparation of AEC catalyst for the transesterification process were calcination temperature of 1000 °C, calcination time of 4 h, and anthill proportion of 20% to achieve 97.13% yield of biodiesel from virgin vegetable oil. At the same optimum parameters, the yield of biodiesel from waste vegetable oil was found to be 70.92%.

中文翻译：

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蚁丘和蛋壳复合催化剂的开发：从原始植物油和废植物油生产生物柴油的优化研究

这项研究的主要目的是从蚁丘和鸡卵壳中开发一种复合材料，并将其用作从原始植物油和废植物油合成生物柴油的催化剂。蚁丘-蛋壳复合（AEC）催化剂是使用初期湿润浸渍法制备的。应用中央复合设计（CCD）研究催化剂制备参数（煅烧温度，煅烧时间和AEC中的蚁丘比例）对两种油中生物柴油收率的影响。基于CCD，开发了两个二次模型，以将AEC准备参数与两个响应相关联。进行方差分析（ANOVA）来验证模型的可靠性，并确定主要影响实验设计响应的因素。优化结果表明，两种油模型的生物柴油产率预测值与实验值基本吻合。酯交换过程中制备AEC催化剂的最佳条件是煅烧温度为1000°C，煅烧时间为4 h，蚁丘比为20％，以从原始植物油中获得97.13％的生物柴油收率。在相同的最佳参数下，废弃植物油中生物柴油的产率为70.92％。来自原始植物油的生物柴油产率为13％。在相同的最佳参数下，废弃植物油中生物柴油的产率为70.92％。来自原始植物油的生物柴油产率为13％。在相同的最佳参数下，废弃植物油中生物柴油的产率为70.92％。