5MeV电子加速器辐照对甲酸循环分离南荻木质纤维素的影响

Effects of 5-MeV electron accelerator irradiation on cycling separation of lignocellulose from Triarrhena lutarioriparia by formic acid

研究5 MeV电子加速器辐照(吸收剂量400 kGy)对甲酸循环分离南荻纤维素、木质素和木糖的影响,并对南荻纤维素酶解效果和结构特征进行分析。结果表明:辐照组南荻经甲酸循环分离,纤维素平均纯度达81.13%,木质素和木糖回收率分别为28.68%和10.16%,均高于对照组样品;随着循环次数的增加,木糖浓度和木质素纯度升高,最终对照组和辐照组南荻木糖浓度分别为31.35 mg/mL和37.35 mg/mL,木质素纯度均超过90%。傅里叶变换红外光谱和X射线衍射分析表明,经甲酸分离的南荻纤维素发生甲酰化修饰,结晶度提高,同时,南荻甲酸纤维素酶解120 h转化率达到54.30%~57.47%,显著高于南荻原料。采用甲酸循环分离工艺能够有效分离南荻木质纤维素组分。

The effect of 5-MeV electron accelerator irradiation of 400 kGy on the formic acid cycling separation of cellulose,lignin,and xylose from Triarrhena lutarioriparia(TL)were studied,and the enzymatic conversion rate and structural characteristics of TL cellulose were analyzed.For 400 kGy irradiated TL,the results revealed that the average purity of cellulose was 81.13%and the recovery of lignin and xylose were 28.68%and 10.16%,respectively,which were higher than those of the unirradiated sample.The recovery of cellulose,concentration of xylose,and purity of lignin increased with the increase in cycle times.The final concentration of xylose for pre-and post-irradiated TL were 31.35 mg/mL and 37.35 mg/mL,respectively,and the purity of lignin was more than 90%.Fourier transform infrared and X-ray diffraction results revealed that TL cellulose separated by formic acid were formylated and exhibited high crystallinity.The enzymatic conversion rate of TL cellulose was 54.30%-57.47%after hydrolysis for 120 h,this rate was considerably higher than that of TL.These results indicated that the formic acid recycling fractionation process could effectively separate TL lignocellulosic components,which could support its large-scale utilization.