The dry washing method is an alternative to replace water washing, thereby reducing the negative impacts of contamination. However, commercial adsorbents come from industrial processes that, due to their composition, may not be such a sustainable resource in the global biodiesel production process. In this study, the use of organic residues, such as sawdust, coconut fiber, nutshell, rice husk, and water hyacinth fiber, were proposed as bioadsorbents for the purification of biodiesel from waste cooking oil. Quality parameters such as the acid number, water content, and free and total glycerin content were evaluated and compared with those after purification with commercial adsorbents (Magnesol and Amberlite BD10DRY). Promising results were obtained using sawdust in the purification process, achieving a reduction in the acid number value of 31.3% respect to the unpurified biodiesel. Indeed, the reduction with sawdust was more efficient than with Amberlite BD10DRY (that increased the acid number). In addition, sawdust reduced free glycerin by 54.8%, again more efficient than Amberlite BD10DRY. The total glycerin values were similar between commercial adsorbents and sawdust. Water content after purification with sawdust was similar to the obtained with Amberlite BD10DRY and better than with Magnesol (399, 417, and 663 mg/kg respectively). These results show that sawdust can be used as an alternative bioadsorbent in a dry purification method for biodiesel, generating less environmental impact.

中文翻译：

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使用非常规生物吸附剂进行生物柴油干法纯化

干洗法可以替代水洗，从而减少污染的负面影响。然而，商业吸附剂来自工业过程，由于其组成，它们可能不是全球生物柴油生产过程中的可持续资源。在这项研究中，有人提出使用诸如木屑，椰子纤维，果壳，稻壳和水葫芦纤维之类的有机残留物作为生物吸附剂，以从废弃的食用油中纯化生物柴油。评估质量参数，例如酸值，水含量以及游离甘油和总甘油含量，并将其与使用市售吸附剂（Magnesol和Amberlite BD10DRY）纯化后的质量参数进行比较。在纯化过程中使用木屑获得了可喜的结果，酸值降低了31。相对于未纯化的生物柴油，为3％。实际上，用木屑进行的还原比用Amberlite BD10DRY进行的还原更为有效（增加了酸值）。此外，木屑使游离甘油减少了54.8％，再次比Amberlite BD10DRY效率更高。商业吸附剂和锯末之间的总甘油值相似。用木屑净化后的水含量与使用Amberlite BD10DRY所获得的相似，并且比用镁碱更好（分别为399、417和663 mg / kg）。这些结果表明，木屑可以用作生物柴油干法纯化方法中的替代生物吸附剂，对环境的影响较小。8％，再次比Amberlite BD10DRY高效。商业吸附剂和锯末之间的总甘油值相似。用木屑净化后的水含量与使用Amberlite BD10DRY获得的水含量相似，并且比用镁碱更好（分别为399、417和663 mg / kg）。这些结果表明，木屑可以在生物柴油的干法纯化方法中用作替代生物吸附剂，对环境的影响较小。8％，再次比Amberlite BD10DRY高效。商业吸附剂和锯末之间的总甘油值相似。用木屑净化后的水含量与使用Amberlite BD10DRY获得的水含量相似，并且比用镁碱更好（分别为399、417和663 mg / kg）。这些结果表明，木屑可以用作生物柴油干法纯化方法中的替代生物吸附剂，对环境的影响较小。