混合酸催化水解白酒丢糟的研究

STUDY ON HYDROLYSIS OF DISTILLERS GRAINS BY MIXED ACID AS CATALYST

以还原糖浓度和糠醛生成量为指标,通过正交试验方法优化混合酸催化水解白酒丢糟的工艺条件,并分析丢糟酸解前后的结构特性。结果表明,丢糟在温度为100℃、固液比为1:12、混合酸浓度为2.5%的最优条件下催化水解120 min,可获得59.32 g/L还原糖,抑制物糠醛的生成量仅为8.37 g/L。结构特性分析表明,酸水解后的丢糟形态结构变化明显,木质纤维结构被破坏,其中的纤维素和半纤维素组分发生降解,酸解残渣的相对结晶度提高。

The mixed acid-catalyzed hydrolysis conditions of distillers grains were studied and optimized with the index of the concentration of reducing sugar and the yield quantity of furfural. The results showed that the optimal conditions for catalytic hydrolysis are reaction temperature 100 ℃, solid-liquid ratio（S/L） 1 ： 12, mixed acid concentration 2.5% and reaction time 120 min. The concentration of reducing sugar and the yield quantity of furfural is 59.32 g/L and 8.37 g/L under optimized conditions, respectively. According to the analysis of structural characteristics, the structural modifications undergone by acid hydrolysis are pronounced in comparison to that of distillers grains. Remarkably, the lignocellulosic structure was severely disrupted leading to the increasing surface exposure and porosity. It is proved that the composition of cellulose and hemicelluloses weres hydrolyzed partially and there was an increase of the crystallinity index when distillers grains was subjected to acid hydrolysis.