Abstract Microalgae have been considered as a potential candidate for biodiesel feedstock. Single-stage simultaneous extraction–transesterification process is proposed for simpler and more effective biodiesel conversion. In this study, the experiment of biodiesel production from microalgae Spirulina sp. was performed in a batch-stirred reactor using palm oil as a co-solvent of methanol and catalyzed by potassium hydroxide at a percentage of 1 wt% (w/w of palm oil). The effects of methanol–palm oil molar ratio, palm oil–microalgae weight ratio, and temperature on biodiesel yield were investigated. The results showed that the best biodiesel yield was 85.28% (99.01% of partial biodiesel yield from palm oil and 16.69% of partial biodiesel yield from dry microalgae), obtained at a methanol–palm oil molar ratio of 10:1, a palm oil–microalgae weight ratio of 5:1, and at a temperature of 60°C. Upon comparison, the overall yield increased by 34.59% (37.73% of partial biodiesel yield from palm oil and 13.00% of partial biodiesel yield from dry microalgae) than that of the two-stage (conventional) method. Single-stage simultaneous extraction–transesterification process also reduced the number of unsaturated fatty acid components in biodiesel that will lower the biodiesel quality.

中文翻译：

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推进微藻螺旋藻生产生物柴油。通过使用棕榈油作为甲醇共溶剂的同时提取-酯交换工艺

摘要 微藻已被认为是生物柴油原料的潜在候选者。单阶段同时提取-酯交换工艺被提议用于更简单和更有效的生物柴油转化。在这项研究中，从微藻螺旋藻生产生物柴油的实验。在间歇搅拌反应器中进行，使用棕榈油作为甲醇的共溶剂，并由 1 wt% (w/w 棕榈油) 的氢氧化钾催化。研究了甲醇-棕榈油摩尔比、棕榈油-微藻重量比和温度对生物柴油产量的影响。结果表明，在甲醇-棕榈油摩尔比为 10:1 时获得的最佳生物柴油产量为 85.28%（棕榈油部分生物柴油产量的 99.01% 和干微藻部分生物柴油产量的 16.69%），棕榈油-微藻重量比为 5:1，温度为 60°C。相比之下，总产量比两阶段（常规）方法提高了 34.59%（棕榈油部分生物柴油产量的 37.73% 和干微藻部分生物柴油产量的 13.00%）。单阶段同时提取-酯交换过程还减少了生物柴油中不饱和脂肪酸组分的数量，这会降低生物柴油的质量。