A Novel Combined Pretreatment Method for Rice Straw Using Optimized EMIM[Ac] and Mild NaOH

作者：Raeisi S Morteza; Tabatabaei Meisam^*; Ayati Bita^*; Ghafari Akram; Mood Sohrab Haghighi

来源：Waste and Biomass Valorization, 2016, 7(1): 97-107.

DOI：10.1007/s12649-015-9437-5

• Combined pretreatment
• EMIM[Ac]
• Mild alkali extraction
• Lignin removal
• Rice straw

Combined pretreatment methods for improving sugar yield as well as the economic aspects of lignoethanol production processes have gained a great deal of interest. However, most investigations involving such methods have been conducted under optimum conditions. Such fully-optimized combinations although improve enzymatic digestion, they could also degrade cellulose structure resulting in reduced sugar yield in some cases. The present study was set to prepare rice straw for the 1-ethyl-3methylimidazolium acetate pretreatment step (2 h, 120 degrees C), by mild alkaline extraction (30 min, 80 degrees C, 0.3 % NaOH) with a focus on only 30 % lignin removal to minimize the hemicelluloses degradation. Moreover, the effect of size reduction (<0.42 mm and <2 cm) was also investigated. The results showed that the novel combination method based on only 30 % lignin removal led to an increased sugar yield by 17 %. Unexpectedly, although IL pretreatment needs material to be ground (<0.42 mm), the difference in sugar yields for the two sized tested was negligible.

• 出版日期2016-2