This study investigated the potential application of an active biocatalyst from pawpaw (Carica papaya) trunk for the direct microwave irradiation-aided transesterification of kariya (Hildegardia barteri) seed oil (KSO) with methanol to obtain biodiesel. The transesterification process involved was modeled, and the effects of the essential process input variables on the kariya seed oil methyl ester (KSOME) yield were examined, followed by the optimization of the input variables to maximize the KSOME yield, using the Taguchi orthogonal array design method. The biocatalyst was produced with a calcination process in a muffle furnace at 200–1000 °C, and each sample obtained was characterized by a scanning electron microscope equipped with energy-dispersive X-ray spectroscopy (SEM–EDX) to determine the best temperature. The calcined pawpaw trunk ash (CPTA) produced at the best temperature of 400 °C was further characterized using X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and physisorption analyses. The CPTA at 400 °C produced a strong catalytic activity due to its morphology, metallic composition (K (23.85%), and Ca (15.40%)), crystalline structure, the average pore size of 32.2 nm, and a surface area of 0.64 m² g⁻¹. The best operating conditions established for the transesterification process were a methanol / KSO molar ratio of 10.5:1, CPTA loading of 0.5 wt%, microwave heating power of 300 W, and reaction time of 2 min, with a maximum KSOME yield of 98.50 ± 0.60 wt%. The quality of the KSOME produced satisfied the American standard specifications for biodiesel. Both KSO and pawpaw trunk could serve as inexpensive feedstock for sustainable and renewable production of biodiesel. The intensification of the transesterification process using microwave irradiation drastically shortened the reaction time needed for maximum biodiesel yield. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

中文翻译：

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田口正交阵列微波辐射辅助卡里亚籽油酯交换工艺优化：木瓜树干作为一种新型生物催化剂

本研究探讨了一种来自木瓜( Carica papaya ) 树干的活性生物催化剂在直接微波辐射辅助的kariya ( Hildegardia barteri )酯交换中的潜在应用。) 种子油 (KSO) 与甲醇获得生物柴油。对所涉及的酯交换过程进行建模，并检查基本过程输入变量对 kariya 种子油甲酯 (KSOME) 产量的影响，然后使用田口正交阵列设计优化输入变量以最大化 KSOME 产量方法。生物催化剂是在马弗炉中在 200-1000°C 下通过煅烧过程生产的，每个样品都通过配备能量色散 X 射线光谱 (SEM-EDX) 的扫描电子显微镜进行表征，以确定最佳温度。使用 X 射线衍射 (XRD)、傅里叶变换红外 (FTIR) 光谱和物理吸附分析进一步表征了在 400 °C 的最佳温度下生产的煅烧木瓜树干灰 (CPTA)。² 克^-1。为酯交换过程建立的最佳操作条件是甲醇 / KSO 摩尔比为 10.5:1，CPTA 负载量为 0.5 wt%，微波加热功率为 300 W，反应时间为 2 min，最大 KSOME 产率为 98.50 ± 0.60 重量％。KSOME生产的质量满足美国生物柴油标准规范。KSO 和木瓜树干都可以作为生物柴油可持续和可再生生产的廉价原料。使用微波辐射的酯交换过程的强化大大缩短了获得最大生物柴油产量所需的反应时间。© 2021 化学工业协会和 John Wiley & Sons, Ltd