Abstract Biodiesel production from microalgae is viable but faces scale-up challenges. The main drawbacks in the industrial production of biodiesel are high-water content in the biomass (~80%) and the numbers of process stages involved in its production. Using direct transesterification is taken into account to be a good solution; because lipid-extraction and transesterification processes are completed in one step. This converts wet biomass directly into biodiesel. This study evaluates a single-step, environmentally-friendly method that directly converts wet microalgae into biodiesel directly with the involvement of supercritical carbon dioxide. Carbon dioxide is exploited in a supercritical state to simultaneously extract lipids from algal biomass impregnated with 15 cc ethanol per 1 g dry microalgal and transesterify that extract to generate fatty-acid-ethyl esters. Wet microalgal biomass of Nannochloropsis oculata was used as the biomass feed for this process. Its biodiesel production efficiency is impacted by temperature and water content. Water has a negative effect on productivity at temperatures

中文翻译：

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利用超临界二氧化碳提取将浸渍乙醇的湿微藻直接转化为生物柴油的新见解

摘要 利用微藻生产生物柴油是可行的，但面临扩大规模的挑战。生物柴油工业生产的主要缺点是生物质中的高含水量 (~80%) 和生产过程中涉及的工艺阶段数量。考虑使用直接酯交换是一个很好的解决方案；因为脂质提取和酯交换过程是一步完成的。这将湿生物质直接转化为生物柴油。本研究评估了一种单步、环保的方法，该方法在超临界二氧化碳的参与下直接将湿微藻直接转化为生物柴油。在超临界状态下利用二氧化碳从每 1 g 干微藻浸渍有 15 cc 乙醇的藻类生物质中同时提取脂质，并将该提取物进行酯交换以生成脂肪酸乙酯。Nannochloropsis oculata 的湿微藻生物质用作该过程的生物质饲料。其生物柴油生产效率受温度和含水量的影响。水在温度下对生产力有负面影响