Here, a cost-effective route for the preparation of biodiesel (BD) from waste cooking oil (WCO) as an alternative eco-friendly fuel and lubricant via catalytic transesterification process using simple base catalyst was demonstrated. Physical and chemical characterization based on FT-IR, ¹H-NMR, and ¹³C-NMR spectroscopy reveals that free carboxylic acid functionality successfully alters to methyl ester of same hydrocarbon chain during the reaction. The BD was characterized by its physical, fuel characteristics including density, viscosity, acid value, flash point, pour point, and foaming tendency, and compared with existing diesel fuel in accordance with ASTM test standard. Prepared BD showed excellent fuel efficiency with higher flash (142 °C) and fire point (147 °C) than the existing diesel fuel. In order to use these synthetic biodiesel esters as advanced green lubricants, their lubrication behavior was tested and compared with hydrocarbon base oil hexadecane (HD). The macrotribological results showed the biodiesel significantly reduced the coefficient of friction by a maximum ~ 43% and specific wear rate ~ 71% in comparison with that of HD at variable applied load. The lubricating efficiency of prepared BD was found to be a similar trend in microtribometric experiments with reciprocating sliding motion under variable loads with similar contact pressure (P_m ~ 1.36–1.95 GPa) as demonstrated in macrotribological rotating motion. Due to polar nature of biodiesel, it deposits on the contact interface and provides a thick molecular film, which may be responsible for enhanced tribological behavior compared with pristine hydrocarbon oil.

在此，展示了一种经济有效的途径，可通过使用简单的碱催化剂进行催化酯交换过程，从废弃的食用油（WCO）中制备生物柴油（BD）作为替代的环保燃料和润滑剂。基于FT-IR，¹ H-NMR和^13的物理和化学表征C-NMR光谱表明，在反应过程中，游离羧酸官能团成功地改变为相同烃链的甲酯。BD的特征在于其物理，燃料特性（包括密度，粘度，酸值，闪点，倾点和起泡趋势），并根据ASTM测试标准与现有柴油进行了比较。制备的BD具有出色的燃油效率，比现有柴油具有更高的闪蒸（142°C）和着火点（147°C）。为了将这些合成生物柴油酯用作高级绿色润滑剂，对它们的润滑性能进行了测试，并将其与烃基油十六烷（HD）进行了比较。宏观摩擦学结果表明，与HD在可变负载下相比，生物柴油最大程度地降低了摩擦系数，最大降低了〜43％，比磨损率降低了约71％。在微摩擦学实验中，在具有相似接触压力的可变载荷下往复滑动运动的情况下，发现制备的BD的润滑效率具有类似的趋势（P_米 所证明在macrotribological旋转运动〜1.36-1.95 GPa）的。由于生物柴油的极性性质，它沉积在接触界面上并提供厚的分子膜，与原始烃油相比，这可能导致摩擦性能增强。