Abstract

The utilization of algal biomass residue after lipid extraction for other purposes can lead to maximum usage of algal biomass and economically beneficial microalgal biodiesel technology. In this study, the performance and economic potential of the conversion of Scenedesmus sp. lipids to biodiesel over lipid extracted algae (LEA) derived catalysts were investigated. The lipid extracted algae (LEA) derived catalysts (Ni/C and Ni/Fe₃O₄-C) were synthesized by impregnation technique and characterized using different analytical tools. The biodiesel conversion of 96.43%, 98.5% and 95.12% was achieved using biochar (C), Ni/C, and Ni/Fe₃O₄-C respectively under the following conditions: reaction time (4 h), temperature (60 °C), methanol to oil molar ratio (30:1) and catalyst dosage (15% w/w of oil). The findings from this study have shown that the use of lipid extracted algae derived catalysts reduced the unit production cost of microalgal biodiesel from 2.03 $/kg to (1.70–1.74 $/kg) when compared to homogeneous catalyst. Among the lipid extracted algae derived catalysts, the use of Ni/C catalyst gave the lowest unit production cost (1.70 $/kg) for biodiesel production from microalgae. The recyclability potential of the LEA derived catalysts could improve the economic viability of the process. The payback period in the range of 1.32 yr–5.57 yr obtained using LEA derived catalysts was below the lifespan of the project (10 years), suggesting that the proposed microalgal biodiesel production is economically feasible.

摘要

将脂质提取后的藻类生物质残渣用于其他目的可以最大限度地利用藻类生物质和经济上有益的微藻生物柴油技术。在这项研究中，栅藻的转化性能和经济潜力。研究了通过脂质提取藻类 (LEA) 衍生的催化剂将脂质转化为生物柴油。脂质提取的藻类 (LEA) 衍生催化剂 (Ni/C 和 Ni/Fe ₃ O ₄ -C) 通过浸渍技术合成并使用不同的分析工具进行表征。使用生物炭 (C)、Ni/C 和 Ni/Fe ₃ O _{4实现了 96.43%、98.5% 和 95.12% 的生物柴油转化率}-C 分别在以下条件下：反应时间 (4 h)、温度 (60 °C)、甲醇与油的摩尔比 (30:1) 和催化剂用量 (油的 15% w/w)。这项研究的结果表明，与均相催化剂相比，使用脂质提取的藻类衍生催化剂将微藻生物柴油的单位生产成本从 2.03 美元/千克降低到（1.70-1.74 美元/千克）。在脂质提取的藻类衍生催化剂中，使用 Ni/C 催化剂使微藻生产生物柴油的单位生产成本最低（1.70 美元/千克）。LEA 衍生催化剂的可回收潜力可以提高该工艺的经济可行性。使用 LEA 衍生催化剂获得的 1.32 年至 5.57 年的投资回收期低于项目的寿命（10 年），