乙酸脱除天然竹纤维木质素的研究

以慈竹为研究对象,对常压下乙酸脱除天然竹纤维中的木质素进行了探讨。以反应温度、乙酸体积分数、催化剂硫酸体积分数和反应时间为单因子,考察这些因素对天然竹纤维木质素脱除率的影响。结果表明:影响因素从大到小依次为反应温度、催化剂硫酸体积分数、乙酸体积分数和反应时间。正交试验结果表明,乙酸在脱除天然竹纤维木质素的过程中也脱除了部分半纤维素和纤维素。结合木质素脱除率、半纤维脱除率和纤维素脱除率,得到了最佳工艺条件,即90℃,乙酸体积分数88%,硫酸体积分数0.3%,反应时间3 h,在该条件下木质素的脱除率达到55.84%。

Study on removing the lignin of natural bamboo fibers by acetic acid

Based on Sinocalamus affinis,this thesis conducts a study on removing lignin in natural bamboo fibers under atmosphere pressure by acetic acid.First,it studies reaction temperature,volume fraction of acetic acid,volume fraction of sulfuric acid catalyst and reaction time as single factors to find their respective impact on removing lignin of original bamboo fibers.The results show that their influence degrees rank in a decreasing order,i.e.,reaction temperature,volume fraction of sulfuric acid catalyst,volume fraction of acetic acid and reaction time.Next,it does an orthogonal experiment,whose results display that some hemicelluloses and celluloses are removed when acetic acid removes lignin in natural bamboo fibers.In consideration of the removal rates of lignin,hemicellulose and cellulose,the optimal operating conditions are obtained,that is,reaction temperature is 90 ℃,the volume fraction of acetic acid is 88 %,the volume fraction of sulfuric acid is 0.3 %,and the reaction time is 3 hours.Under the conditions,the removal rate of lignin can be 55.84 %.