Abstract

This study aims to validate and investigate the power of green coconut biomass (mesocarp) for the production of levulinic acid (LA). Several methods have been applied to characterize this biomass physically and chemically, in order to provide an assertive direction in the use of this residue. The LA conversion was performed with different catalysts, hydrochloric acid (HCl) and sulfuric acid (H₂SO₄). The conversion reactions were performed by varying time (t) and temperature (T) according to the optimum conditions described in the literature for each catalyst. In order to increase the yield of LA, the biomass was pretreated with sulfuric acid (H₂SO₄), sodium hydroxide (NaOH), and water (H₂O in soxhlet) solutions. There were significant increases in the release of sugars, xylose, and arabinose (p < 0.05), after the pretreatments with NaOH solution (assay 9). The maximum yield of LA was 43.8% under the following reaction conditions: 3 h, 180 °C, and 0.045 M of hydrochloric acid (HCl). In addition to the levulinic acid, the 5-hydroxymethylfurfural (HMF) and furfural (FF) furanics were also quantified with yields of 13.4% and 4.4% respectively. The results have shown the power of green coconut shells within biorefineries to produce value-added chemicals.

Graphic Abstract

中文翻译：

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使用不同方法从椰子渣（Cocos nucifera）生产乙酰丙酸

摘要

本研究旨在验证和研究绿色椰子生物质（中果皮）生产乙酰丙酸 (LA) 的能力。已经应用了几种方法来从物理和化学上表征这种生物质，以便为这种残留物的使用提供一个明确的方向。LA 转化使用不同的催化剂、盐酸 (HCl) 和硫酸 (H ₂ SO ₄ ) 进行。根据文献中描述的每种催化剂的最佳条件，通过改变时间 (t) 和温度 (T) 来进行转化反应。为了提高LA的收率，生物质用硫酸（H ₂ SO ₄）、氢氧化钠（NaOH）和水（H ₂O in soxhlet) 溶液。用 NaOH 溶液预处理后，糖、木糖和阿拉伯糖的释放显着增加（p < 0.05）（测定 9）。在以下反应条件下，LA 的最大产率为 43.8%：3 小时、180 °C 和 0.045 M 的盐酸 (HCl)。除了乙酰丙酸，5-羟甲基糠醛 (HMF) 和糠醛 (FF) 呋喃也分别以 13.4% 和 4.4% 的产率被量化。结果表明，生物精炼厂内的绿色椰子壳具有生产增值化学品的能力。

图形摘要