Sono-modified halloysite nanotube with NaAlO2 as novel heterogeneous catalyst for biodiesel production: Optimization via GA_BP neural network

This work reported the one-pot synthesis of the promising, cheap and green heterogeneous nanocatalyst for biodiesel production . The halloysite nanotube (HNT) was impregnated with 40  wt % NaAlO 2 (SA) and the assistance of ultrasonic helped to achieve a better and more stable modification. The resulting 0.4SA/HNTs-UI catalyst was applied in catalyzing the transesterification of palm oil with methanol, using a GA_BP neural network to train and predict the optimal values of reaction parameters. The test results proved the prediction accuracy of the model with R 2  = 0.989. The catalyst possessed excellent performance, and the maximum biodiesel yield of 99.15% was achieved with the catalyst loaded amount of 8.82  wt %, methanol to oil molar ratio of 16.79 and transesterification temperature of 65.12 °C. Besides, the physicochemical properties of the purified transesterification product were in accordance with the ASTM D 6751 standard of biodiesel .