超临界流体技术制备生物柴油进展及前景

Progress and prospect on supercritical fluids technology in biodiesel production

超临界流体技术制备生物柴油不使用催化剂,生产过程清洁环保,是极具发展潜力的绿色可再生能源生产技术。本文首先简述超临界流体的特点及其用于生物柴油制备的物理、化学基础;其次详细分析超临界流体技术制备生物柴油的过程中反应温度、反应压力、醇油摩尔比、低碳醇种类、水、脂肪酸、反应器及反应形式等工艺控制条件对反应的影响和原因,并介绍超临界流体制备生物柴油中的过程强化方法和技术经济性。尽管超临界流体制备生物柴油具有原料适应性好、投资和运行成本低、生产过程清洁等优点,但存在反应条件苛刻、甲醇用量高等问题,从工业化角度指出使用廉价废弃油脂原料降成本、调节原料酸值降低反应苛刻度、连续化和大型化是超临界流体制备生物柴油技术的重点提升方向。

As an environment-friendly biodiesel process,the catalyst-free supercritical fluids(SCF)technology shows great potential in green and renewable energy production.The physical and chemical foundation in SCF technology for biodiesel production was firstly discussed.The effects of process factors,including reaction temperature,pressure,alcohol, water,free fatty acid and reactor type,on the SCF transesterification were then discussed in detail.The intensification measures used in SCF biodiesel process and the techno-economic analysis were also presented.Though the SCF biodiesel process showed its merits of good feedstock adaptability,low equipment and operation cost,and catalyst-free feature,the shortcomings of harsh reaction condition and high methanol dosage hindered its industrialization.The future improvements should focus on the reduction of biodiesel cost,the decrease of reaction harshness,and continuity and industrialization.