改性TiO_(2)-太阳光协同强化秸秆产糖的研究

Synergistic Enhancement of Straw Sugar Production by Modified TiO_(2)under Sunlight Irradiation

为了强化生物质能源的清洁利用,提高生物质糖转化率,合成了L-缬氨酸改性二氧化钛复合催化剂;随后以稻草秸秆为原料,木质素去除率与还原糖产量为目标,通过改性二氧化钛-太阳光协同预处理强化秸秆酶解糖化效率。过程中考察了催化剂种类、浓度、pH、太阳光光照时间以及光照方式对秸秆还原糖转化率的影响。在单因素试验基础上,对工艺参数进行了正交试验优化。SEM与FT-IR分析结果显示,L-缬氨酸成功负载于二氧化钛颗粒上;形成的复合催化剂联合太阳光辐照可有效强化秸秆还原糖转化率。综合考虑经济性因素,最终方案选择催化剂浓度为35 mg/L、pH为6.0、预处理时间70 min。验证试验显示,木质素去除率可达93.1%。预处理后,酶解糖化过程采用光暗交替循环方案,酶载量20 FPU/g,其还原糖转化率可达117.3 mg/g,还原糖转化率非常显著。

In order to strengthen the clean utilization of biomass energy and improve the conversion rate of biomass sugar,L-valine modified titanium dioxide composite catalyst was synthesized in this study.Subsequently,using lignin removal efficiency and reducing sugar yield as index,the biomass pretreatment and enzymatic saccharification from straw material were enhanced by combining the modified titanium dioxide and solar light.During the process,the effects of catalyst type,catalyst concentration,pH,sunlight exposure time,and lighting method on the reducing sugar yield were investigated.On the basis of single factor experiments,orthogonal experiments were conducted to optimize the process parameters.The results of SEM and FT-IR showed that L-valine was successfully loaded onto titanium dioxide particles;The composite catalyst in combination with sunlight irradiation can effectively enhance the reducing sugar yield of straw.Taking cost-effectiveness into consideration,the optimum conditions determined statistically via orthogonal methodology were modified TiO 2 catalyst concentration(35 mg/L),pH(6.0),pre-treatment time(70 mins)for maximum lignin removal efficiency(93.1%).After pre-treatment,the enzymatic hydrolysis and saccharification process adopted a light-dark alternating cycle scheme with an enzyme load of 20 FPU/g,and the reduction sugar yield could reach 117.3 mg/g,which was very significant.