Regenerated Cellulose Membrane from Peanut Shell for Biodiesel Purification

Biodiesel purification by water washing has been proved to be an unattractive process from an economic and environmental point of view. In this work, we propose the use of regenerated cellulose membranes from peanut shell as an alternative in the biodiesel purification. The preparation of the membranes was optimized from a central composite design, resulting in dense and non-porous membranes. However, in contact with biodiesel, the membranes undergo expansion due to the retention of methanol, water, and glycerol molecules, allowing the permeation of fatty acid methyl esters. The filtered biodiesel presents quality parameters, such as total ester content of 98.3 ± 1.4% and free glycerol content < 0.02%, in agreement with the main regulatory agencies. The regenerated cellulose membranes from peanut shell are easily prepared, with high repeatability (relative standard deviation (RSD) < 1.8%) and are presented as an economical and environmental solution for the biodiesel purification.水洗法应用于生物柴油纯化的工艺，经证实从经济与环境维度均不具备应用吸引力。本研究提出以花生壳基再生纤维素膜（regenerated cellulose membranes）作为生物柴油纯化的替代方案。通过中心复合设计（central composite design）优化该膜的制备工艺，最终获得致密无孔的纤维素膜。但该膜与生物柴油接触后，因截留甲醇、水与甘油分子而发生溶胀，使得脂肪酸甲酯可渗透通过。经该膜过滤后的生物柴油各项质量指标均符合主流监管机构要求，其中总酯含量为98.3 ± 1.4%，游离甘油含量低于0.02%。花生壳基再生纤维素膜制备简便、重复性优异（相对标准偏差（relative standard deviation, RSD）< 1.8%），是一种兼具经济性与环境友好性的生物柴油纯化方案。