Pyrolysis of oil palm biomass residue can convert the rich organic matter in biomass into sustainable green energy, thereby addressing the challenge of surplus oil palm biomass residue generated during cultivation. Nonetheless, the pyrolysis of oil palm leaves (OPLs) has received limited attention. In this study, design of experiment-response surface methodology (DoE-RSM) was employed to identify the optimal combination of reaction temperature, residence duration, and nitrogen (N₂) flow rate for maximum biochar yield. The elemental analysis, high heating value (HHV), functional group, morphology, pore structure, and thermal behavior were assessed. By varying the operational parameters using response surface methodology, the biochar yield increased by 32.6–85.3%. The DoE-RSM predicted a theoretical yield of 52.1% at 344 °C, 146 min, and 3.2 scfh N₂ flow rate. The experiment confirmed a comparable yield of 53.7% at the stated parameters. The HHV of 24.14 MJ kg⁻¹ was recorded under optimal conditions, and was comparable to sub-bituminous and bituminous coal. Fourier transform infrared analysis validated the OPL biochar by weakening O-H, C=O, C-OH, and C-H peaks. Scanning electron microscopy images revealed enlarged pores and altered morphology in the OPL biochar. X-ray diffraction showed lower crystallinity of the OPL biochar than the feedstock. Raman spectroscopy showed higher I_D/I_G, indicating a more disordered carbon structure in the OPL biochar. Thermogravimetric analysis confirmed higher temperature for main devolatilization of OPL biochar, and the differential thermogravimetric analysis curve pattern resembled that of Mukah Balingan coal. The findings are helpful for an initiative to convert a large amount of leftover OPLs produced during cultivation and to turn them into high value-added material for a sustainable contribution to a circular carbon economy.

中文翻译：

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油棕叶可用于潜在的可再生次烟煤：通过响应面法和产品表征优化生物炭产量

油棕生物质残渣的热解可以将生物质中丰富的有机物转化为可持续的绿色能源，从而解决种植过程中产生的剩余油棕生物质残渣的挑战。尽管如此，油棕叶（OPL）的热解受到的关注有限。在本研究中，采用实验响应面方法设计 (DoE-RSM) 来确定反应温度、停留时间和氮气 (N2) 流量的最佳组合，以实现最大生物炭产量。对元素分析、高热值（HHV）、官能团、形态、孔隙结构和热行为进行了评估。通过使用响应面法改变操作参数，生物炭产量增加了 32.6-85.3%。DoE-RSM 预测在 344 °C、146 分钟和 3.2 scfh N2 流速下的理论产率为 52.1%。实验证实在规定参数下的可比产率为 53.7%。在最佳条件下记录的HHV 为 24.14 MJ kg ^-1，与次烟煤和烟煤相当。傅里叶变换红外分析通过削弱 OH、C=O、C-OH 和 CH 峰来验证 OPL 生物炭。扫描电子显微镜图像显示 OPL 生物炭的孔隙扩大，形态发生改变。X 射线衍射显示 OPL 生物炭的结晶度低于原料。拉曼光谱显示较高的 I _D /I _G，表明 OPL 生物炭中的碳结构更加无序。热重分析证实 OPL 生物炭的主要脱挥发分温度较高，并且差热重分析曲线模式与 Mukah Balingan 煤的曲线模式相似。这些发现有助于将种植过程中产生的大量剩余 OPL 转化为高附加值材料，为循环碳经济做出可持续贡献。