Enhanced saccharification of rice straw using combined ultra-high pressure and ionic liquid microemulsion pretreatments
Energy efficiency ratio is significant in completely estimating lignocellulosic biomass pretreatment. In this work, rice straw (RS) was pretreated by ultra-high pressure (UHP), ionic liquid microemulsion (ILM), and a combination of UHP and ILM (ILM + UHP) at mild temperature. The chemical composition, crystalline structure, surface morphology, and enzymatic hydrolysis of untreated and pretreated RS samples were compared. After ILM pretreatment ([Emim]Ac/cyclohexane/Triton X-100/n-butanol = 0.25/0.15/0.45/0.15) at 500 MPa, 50 °C for 4 h, the cellulose content of the regenerated RS increased by 62.5, 66.2% of the lignin was removed, 37.3% of crystallinity index decreased, and the reducing sugar yield of 89.6% was achieved. All results show that the ILM + UHP pretreatments were more effective than sole UHP or ILM treatment at low temperature.
KeywordsLignocellulosic biomass Combination pretreatment Ultra-high pressure Ionic liquid microemulsion Enzymatic hydrolysis
This work was supported by Fund for National Natural Science Foundation of China (21706040), Guangdong Province Innovation School Project (2015KQNCX061, GDOU2015050240), Fund of Key Laboratory of Aquatic Product Processing, Ministry of Agriculture, China (B16387), and Fund of Scientific Research Start-up Funds of Guangdong Ocean University (E15178).
Compliance with ethical standards
Conflict of interests
The authors declare no competing financial interest.
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