Poor cold flow is the main factor that affects biodiesel fuel utilization in cold regions during winter, owing to the high melting point of saturated fatty acids. In the present study, we produced fatty acid methyl esters from shea butter by transesterifying it with methanol. The esterification process was catalyzed by HSO. We obtained an optimum ester conversion of 99.54 wt% using 0.5 wt% HSO and 1.2 wt% KOH. Subsequently, we applied additive winterization to improve the cold-flow properties of the obtained shea butter biodiesel using the nonionic surfactants sorbitan palmitate and sorbitan stearate. We selected cooling temperatures between the cloud point and the pour point of shea butter biodiesel, and achieved a 8–10 K reduction in the cloud point at 294 K using 0.5–1.0 wt% sorbitan stearate. Additive winterization significantly improved the low-temperature flow properties of shea butter biodiesel.

中文翻译：

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通过添加剂防冻改善乳木果油生物柴油的冷流性能


由于饱和脂肪酸熔点较高，冷流不良是影响寒冷地区冬季生物柴油利用的主要因素。在本研究中，我们通过乳木果油与甲醇进行酯交换来生产脂肪酸甲酯。酯化过程由 HSO 催化。我们使用 0.5 wt% HSO 和 1.2 wt% KOH 获得了 99.54 wt% 的最佳酯转化率。随后，我们使用非离子表面活性剂脱水山梨糖醇棕榈酸酯和脱水山梨糖醇硬脂酸酯应用添加剂防冻来改善所获得的乳木果油生物柴油的冷流性能。我们选择乳木果油生物柴油的浊点和倾点之间的冷却温度，并使用 0.5–1.0 wt% 脱水山梨糖醇硬脂酸酯在 294 K 下实现了 8–10 K 的浊点降低。添加剂防冻显着改善了乳木果油生物柴油的低温流动特性。