Investigation of accessibility and reactivity of cellulose pretreated by ionic liquid at high loading

Takatsugu Endo; Ei Mon Aung; Shunsuke Fujii; Shota Hosomi; Mitsugu Kimizu; Kazuaki Ninomiya; Kenji Takahashi

doi:10.1016/j.carbpol.2017.08.105

Investigation of accessibility and reactivity of cellulose pretreated by ionic liquid at high loading

Carbohydr Polym. 2017 Nov 15:176:365-373. doi: 10.1016/j.carbpol.2017.08.105. Epub 2017 Aug 25.

Authors

Takatsugu Endo¹, Ei Mon Aung², Shunsuke Fujii³, Shota Hosomi⁴, Mitsugu Kimizu⁵, Kazuaki Ninomiya⁶, Kenji Takahashi⁷

Affiliations

¹ Faculty of Natural System, Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. Electronic address: taendo@mail.doshisha.ac.jp.
² Faculty of Natural System, Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. Electronic address: eimonaung@stu.kanazawa-u.ac.jp.
³ Faculty of Natural System, Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. Electronic address: fujii-sh091@stu.kanazawa-u.ac.jp.
⁴ Faculty of Natural System, Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. Electronic address: hsmst14@gmail.com.
⁵ Industrial Research Institute of Ishikawa, 2-1 Kuratsuki, Kanazawa 920-8203, Japan. Electronic address: mkimizu@irii.jp.
⁶ Institute for Frontier Science Initiatives, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. Electronic address: ninomiya@se.kanazawa-u.ac.jp.
⁷ Faculty of Natural System, Institute of Science and Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. Electronic address: ktkenji@staff.kanazawa-u.ac.jp.

PMID: 28927619
DOI: 10.1016/j.carbpol.2017.08.105

Abstract

High loading of cellulose in ionic liquid (IL) pretreatment is potentially a key technique for cellulose conversion to glucose in biorefining. In this work, to expand the potential use of this high loading technique, the accessibility of microcrystalline cellulose pretreated with an IL across a wide cellulose loading range (5-50mol%) and its relationship with the hydrolytic reactivity were comprehensively investigated. The results show that the estimated cellulose accessibility based on the crystallinity and specific surface area was notably higher in 25mol% loading than that for a conventional loading of 5mol%. Consistently, acid-catalyzed glucose conversion was faster at this high loading, showing that a higher cellulose loading improves the pretreatment efficiency. In contrast, enzymatic hydrolysis was not enhanced by a high cellulose loading. A key difference between the activities in these two hydrolytic reactions is the catalyst size.

Keywords: Cellulose; High loading; Hydrolysis; Ionic liquid; Pretreatment.