In this work, an HCl-catalyzed ethylene glycol (EG) pretreatment was exploited for promoting sugar release from sugarcane bagasse (SCB). The results showed that the combination of HCl and EG could remove the xylan (∼100.0%) and lignin (∼61.3%) in SCB together, which finally resulted in the pretreated substrate having a good efficacy for follow-up enzymatic hydrolysis . The maximum glucose yield of this work was 93.9% and obtained after pretreatment at 130 °C for 60 min with 0.5% HCl and 72 h enzymatic digestion. The analysis of various pretreated or un-pretreated SCB indicated that the changes of surface morphology and internal compositions of SCB were the mainly reasons for its hydrolysis efficiency enhancement. The addition of Tween 80 into hydrolysis process could remarkably shorten hydrolysis time and cellulase dosage from 72 h to 36 h and 20 FPU/g substrate to 10 FPU/g substrate, respectively, meanwhile maintaining a relatively high glucose yield (91.4%).
Jian Shi,Jialin Li,Hui Ma,Donghuai Tu,Qian Zhang,Wei Mao,Jianming Yang,Jian Lu
RuO 2 supported on rutile TiO 2 or SnO 2 has been proved extremely effective for catalyzing the oxidation of HCl into Cl 2 . The supports play a crucial role in the catalyst systems. In this work, Ti-Sn oxides with different Sn/(Sn + Ti) molar ratios (0–0.2) were synthesized by a facile co-precipitation method as supports. The corresponding Ru/Ti-Sn oxide catalysts were investigated in HCl catalytic oxidation and systematically characterized to elucidate the role of Ti-Sn oxide supports on the process. The diffraction, spectroscopy and microscopy results reveal the crystal and surface structures of supports and catalysts. Among all the RuO 2 /Ti 1-x Sn x O 2 catalysts, RuO 2 /Ti 0.97 Sn 0.03 O 2 exhibits the best catalytic activity of 2.6 g Cl 2 ·g cat -1 ·h −1 with only 0.5% Ru loading and excellent stability on stream. Differed from the previous understanding, Ti 0.8 Sn 0.2 O 2 support containing the most rutile phase shows unsatisfying performance. The excessive Sn content renders more crystal disorder and volatile substrate, inevitably lowering the dispersion and stabilization of RuO 2 active phase. However, moderate Sn addition induces well-dispersed SnO 2 and rutile TiO 2 film, facilitating the dispersion of RuO 2 phase on the support surface with more active oxygen species. A large number of oxygen vacancies on Ti 0.97 Sn 0.03 O 2 can act as an active oxygen reservoir and boost catalytic performance.
危险品化学品经营许可证（带存储）