酸解聚玉米秸秆的产物及其形成机制研究

Products and Mechanism of Corn Stalk After Depolymerization with Acid

为了探明酸解聚农作物秸秆的产物及其形成机制,本试验以玉米秸秆为研究对象,硫酸为解聚剂,利用高效液相色谱法检测解聚产物,探讨了不同硫酸浓度、解聚温度对玉米秸秆高分子结构解聚产物分布的影响。结果表明:解聚液中的主要糖类有木糖、阿拉伯糖、葡萄糖,副产物有乙酸、糠醛、5-羟甲基糠醛、阿魏酸和对香豆酸。当解聚温度高于120℃,5%硫酸解聚4 h时有纤维二糖、乙酰丙酸和甲酸生成。7%硫酸80℃解聚4 h时,有纤维二糖产生,说明硫酸浓度和解聚温度对玉米秸秆的解聚产物及其分布有一定的影响。分析并提出了硫酸解聚秸秆机制及副产物的形成途径。

The objective of the paper was to investigate the product and mechanism in the process of depolymerization crop straw with acid. Corn stalk was used as the material to research the effects of acid concentration and temperature on corn stalks product distribution through depolymerization by sulfuric acid in a method of high performance liquid chromatography. The results showed that the major carbohydrates in liquid of the depolymerized corn stalk were xylose,arabinose and glucose,and the major by- products were acetic acid,furfural,5- hydroxymethyl furfural,ferulic acid and p- coumaric acid. When the temperature was higher than 120 ℃,cellobiose,levulinic acid and formic acid were detected in depolymerization liquid after being treated with 5% sulfuric acid for 4 h. In addition,cellobiose could be produced from corn stalk through depolymerization with 7% sulfuric acid for 4 h at 80 ℃. These results indicated that the sulfuric acid concentration and temperature had a certain influence on the yield and distribution of products generated from corn stalk during depolymerization process. Meanwhile,the possible mechanism of depolymerization corn stalk with sulfuric acid and the formation pathway of by- product was put out.