乙二醇法提取棉秆中木质素的研究

Lignin in Cotton Stalk Extraction by Ethylene Glycol

棉秆中的木质素含量约为20%。将棉秆中的木质素进行分离和利用,有望缓解棉秆的资源浪费和环境污染问题。试验采用乙二醇为溶剂提取棉秆中的木质素,考察了反应温度、反应时间、乙二醇浓度、催化剂用量等主要因素对木质素产率的影响。结果表明,提取棉秆中木质素的最佳条件为:反应温度200℃、反应时间3.0 h、乙二醇浓度80%,在此条件下木质素产率达74.6%。采用32%的硫酸作为催化剂可提高棉秆中木质素的产率,当其加入量为溶剂体积的0.50%时,木质素的产率可达80.4%。

Because of its high content of 20% in cotton stalk,the lignin in cotton stalk might be separated for utilization in order to alleviate the problem of resources waste and environment pollution.The lignin was extracted with ethylene glycol as solvent under different temperatures,time,ethylene glycol contents and catalyst amounts.The results showed that the optimal extracting condition were under 200 ℃,reaction time 3.0 h with 80% ethylene glycol,and the yield of lignin was 74.6%.The sulphuric acid of 32% as catalyst could be used to increase the yield of lignin,which reached 80.4% when the dosage was 0.50%.