甘蔗渣纳晶纤维素酸法制备工艺的响应面法优化

Optimizing the acid hydrolysis process of bagasse nanocrystalline cellulose via the surface response method

为了获得甘蔗渣纳晶纤维素酸法制备的最佳工艺条件,基于Box-Behnken试验设计,选取硫酸质量分数、水解时间和水解温度为主要影响因素,采用响应面分析法优化了甘蔗渣纳晶纤维素酸水解制备工艺参数,并建立了二次多项式回归模型。方差分析表明,回归模型较好地反映了纳晶纤维素得率与硫酸质量分数、水解时间、水解温度的关系。甘蔗渣纳晶纤维素最佳的酸水解制备工艺条件为:硫酸质量分数56%,水解时间180 min,水解温度38℃。该条件下纳晶纤维素的得率达到52.93%。酸法制备工艺的响应面优化试验显著提高了甘蔗渣纳晶纤维素的得率,降低了纳晶纤维素的制备成本。

In this paper, we would like to introduce a new approach to optimizing the acid hydrolysis process-of bagasse nanocrystalline cellulose via the surface response method. As is known, nanocrys- talline cellulose enjoys a lot of marvelous behaviors, which make it widely used in the field of food processing, papermaking, environmental protection and renewable medical materials, and so on. However, due to the high cost of nanocrystalline cellulose preparation, its application in industrial fields remains severely restricted. As a major byproduct of the sugar industry, bagasse contains a lot of cellulose, lignin, hemicellulose and other natural polymer substances. If the cellulose of bagasse can be successfully extracted with nanocrystalline cellulose, huge economic and environmental benefits will be brought about to enrich our life and industrial production. It is for this urgent need that we have made great endeavors to explore potential for utilizing bagasse nanocrystallinc cellulose and improve on the processing conditions for its future development. Based on the Box-Behnken design, we have studied and chosen sulfuric acid mass fraction, hydrolytic temperature and hydrolytic time as the three key factors at the five levels. Furthermore, we have optimized the process conditions of bagasse nanocrystalline cellulose by using acid hydrolysis and response surface methodology, and worked out a mathematical model of a second order quadratic equation for the yield of nanocrystalline cellulose. The regression coefficient and variance analysis prove that the regression model is fit for the relationship of bagasse nanocrystalline cellulose yield and sulfuric acid mass fraction, the hydrolytic temperature and hydrolytic time. And, finally, we have managed to optimize the following technological parameters： the maintenance sulfuric acid mass fraction （56%）, the hydrolytic time （180 min）, the hy- drolytic temperature （38 ℃ ）, the yield of bagasse nanocrystalline cellulose that can e achieved （52.93 % ）. The process conditions for the optimization test of bagasse nanocrystalline cellulose by the acid hydrolysis can help significantly raise the yield of bagasse nanocrystalline cellulose, thus, greatly reducing the cost for preparing nanocrystalline cellulose.