Abstract

In this work, a mechanistic model was developed to simulate the kinetics of the production of levulinic acid (LA) from sugarcane bagasse (SCB), rice husk (RH) and soybean straw (SS). The production of LA from those agro-industrial wastes followed the methodology of biorefining in three stages. Experimental data from the third stage (catalytic depolymerization of cellulose) obtained under a wide range of operating conditions were used to estimate the parameters of the model. An optimization procedure based on a genetic algorithm was used to determine the optimal parameter values. The prediction of the concentrations of glucose, 5-HMF and LA using the mechanistic model was particularly accurate, as demonstrated by R² and RMSE. Thereby, a satisfactory concordance was reached between the high yields of LA of 61.1 mol%, 67.7 mol% and 61.4 mol% calculated by the model, and the experimental yields of 60.5 ± 2.1 mol%, 65.2 ± 2.9 mol% and 61.5 ± 4.0 mol% (under optimum conditions of 190 °C, 7.0% w/v of H₂SO₄, 75 min) for SCB, RH and SS, respectively. The biorefining of the agro-industrial wastes under optimum operating conditions allowed a satisfactory catalytic depolymerization of cellulose, regardless of the degree of crystallinity. The estimation of yields led to suggesting a strategy from the point of view of process synthesis and design, integrating SCB, RH and SS to supply their off-season and, thus, to ensure the supply of raw materials in the production of LA.

Graphic abstract

中文翻译：

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动力学模型对木质纤维素生物质基乙酰丙酸生产的动力学见解

摘要

在这项工作中，建立了一个机械模型来模拟由甘蔗渣（SCB），稻壳（RH）和大豆秸秆（SS）生产乙酰丙酸（LA）的动力学。从那些农业工业废料中生产LA，遵循了三个阶段的生物精炼方法。在广泛的操作条件下获得的来自第三阶段（纤维素的催化解聚）的实验数据被用来估计模型的参数。使用基于遗传算法的优化程序来确定最佳参数值。如R ^2所示，使用机理模型预测葡萄糖，5-HMF和LA的浓度特别准确。和RMSE。从而，在由模型计算出的LA的高产率61.1mol％，67.7mol％和61.4mol％之间以及在实验产率60.5±2.1mol％，65.2±2.9mol％和61.5±4.0之间达到了令人满意的一致性。对于SCB，RH和SS分别为mol％（在190°C的最佳条件下，H ₂ SO _4的7.0％w / v ，75分钟）。在最佳操作条件下对农业工业废料进行生物精制，无论结晶程度如何，都可以使纤维素令人满意地催化解聚。对产量的估计导致从工艺综合和设计的角度提出了一种策略，将SCB，RH和SS整合在一起以供应淡季，从而确保LA生产中的原材料供应。

图形摘要