Abstract Raw biodiesel requires purification to remove excess methanol, unreacted and/or partially reacted starting material(s), and residual catalyst. The common practice for biodiesel purification is a series of water washes. These water washes are time consuming, generate a large aqueous waste stream, and can lead to saponification and subsequent emulsion formation. To eliminate water washes, solid materials which are capable of purifying the biodiesel after a short residence time are currently the subject of active investigation. Herein, we investigate the use of coco coir, a product of coconut husks commonly used as orchid planting material, as a bio-derived, biodegradable, and inexpensive drywash material for biodiesel fuel. Overall, we find that coco fiber (1) removes soap concentrations of >3000 ppm in one pass through the column; (2) treats raw biodiesel at volumes which meet or exceed current industry standards; (3) is stable and effective for a time period greater than five years; (4) does not raise free fatty acid levels above acceptable levels; (5) does not add Ca2+ or Mg2+ to the purified fuel; (6) reduces methanol to acceptable levels; and (7) removes free glycerol, even when biodiesel samples are spiked with artificially large quantities of free glycerol.

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从兰花到生物​​柴油：椰壳纤维作为生物柴油燃料的有效干洗材料

摘要 原始生物柴油需要纯化以去除过量的甲醇、未反应和/或部分反应的起始材料和残留催化剂。生物柴油纯化的常见做法是一系列水洗。这些水洗很费时，会产生大量的废水，并可能导致皂化和随后的乳液形成。为了消除水洗，能够在短停留时间后净化生物柴油的固体材料目前是积极研究的主题。在此，我们调查了椰壳纤维（一种通常用作兰花种植材料的椰子壳产品）作为生物柴油燃料的生物衍生、可生物降解且廉价的干洗材料的用途。总的来说，我们发现椰子纤维 (1) 在一次通过色谱柱时去除了 >3000 ppm 的皂浓度；(2) 以达到或超过当前行业标准的数量处理原料生物柴油；(3) 五年以上稳定有效；(4) 不会将游离脂肪酸水平提高到可接受水平以上；(5)净化后的燃料中不添加Ca2+或Mg2+；(6) 将甲醇减少到可接受的水平；(7) 去除游离甘油，即使在生物柴油样品中加入了大量的人为游离甘油。