Chapter 3
Pretreatment of Wheat Straw Using Ionic
Liquids for Bioethanol Production: A
Review
Ibsa Neme and Chandran Masi
Abstract Ethanol production from sustainable and inexpensive farming residues
decreases greenhouse gas emissions, for instance, carbon dioxide, nitrogen dioxide,
sulfur oxide, and eliminate smog from the atmosphere. A certain number of agricultural residues and plentifully misused materials are oat straw, rice straw, and
wheat straw; waste potato, switchgrass, corn steep liquor, sweet sorghum, bagasse,
sugar beet tubers, etc. are used as potential material for bioethanol making in
different countries. Wheat straw deposits are one among the residues produced in
substantial amounts globally, including Ethiopia. However, the elimination of lignin
out of lignocelluloses untreated residues is the most critical step. Various
pretreatment methods are explained before by numerous researchers with chemical,
physical, biological, and ionic liquid pretreatment. This review carefully evaluates
the performance of highly capable and recent techniques of hydrolysis and discusses
the potential of wheat straw residue for bioethanol production, using less energydemanding and more eco-friendlier techniques than the recent commercial
pretreatment techniques. The most popular of these is the ionic liquids (ILs).
Important pretreatment steps by ionic liquids, such as 1-allyl-3-methylimidazolium
chloride,1-ethyl-3-methylimidazolium acetate, 1-butyl-3methylimiazolium,1-ethyl3-methylimidazolium acetate, 1-butyl-3-methylimidazolium hydrogen sulfate,
1-butyl-3-methylimidazolium thiocyanate, 1-ethyl-3-methylimidazolium diethyl
phosphate, 1-methyl-3-(4-sulfobutyl) imidazolium bisulfate, and cholinium taurate,
will be evaluated. Additionally, critical parameters affecting the treatment process,
such as temperature, the ratio of ionic liquids to residue dose, concentration of ionic
liquids, and time taken, would also be discussed.
Keywords Lignocellulosic materials · Pretreatment · Ionic liquids · Bioethanol
I. Neme
Department of Chemical Engineering, College of Biological and Chemical Engineering, Addis
Ababa Science and Technology University, Addis Ababa, Ethiopia
C. Masi (*)
Department of Biotechnology, College of Biological and Chemical Engineering, Addis Ababa
Science and Technology University, Addis Ababa, Ethiopia
e-mail: chandran.chandran@aastu.edu.et
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021
J. Aravind et al. (eds.), Strategies and Tools for Pollutant Mitigation,
https://doi.org/10.1007/978-3-030-63575-6_3
49
Pretreatment of Wheat Straw Using Ionic
Liquids for Bioethanol Production: A
Review
Ibsa Neme and Chandran Masi
Abstract Ethanol production from sustainable and inexpensive farming residues
decreases greenhouse gas emissions, for instance, carbon dioxide, nitrogen dioxide,
sulfur oxide, and eliminate smog from the atmosphere. A certain number of agricultural residues and plentifully misused materials are oat straw, rice straw, and
wheat straw; waste potato, switchgrass, corn steep liquor, sweet sorghum, bagasse,
sugar beet tubers, etc. are used as potential material for bioethanol making in
different countries. Wheat straw deposits are one among the residues produced in
substantial amounts globally, including Ethiopia. However, the elimination of lignin
out of lignocelluloses untreated residues is the most critical step. Various
pretreatment methods are explained before by numerous researchers with chemical,
physical, biological, and ionic liquid pretreatment. This review carefully evaluates
the performance of highly capable and recent techniques of hydrolysis and discusses
the potential of wheat straw residue for bioethanol production, using less energydemanding and more eco-friendlier techniques than the recent commercial
pretreatment techniques. The most popular of these is the ionic liquids (ILs).
Important pretreatment steps by ionic liquids, such as 1-allyl-3-methylimidazolium
chloride,1-ethyl-3-methylimidazolium acetate, 1-butyl-3methylimiazolium,1-ethyl3-methylimidazolium acetate, 1-butyl-3-methylimidazolium hydrogen sulfate,
1-butyl-3-methylimidazolium thiocyanate, 1-ethyl-3-methylimidazolium diethyl
phosphate, 1-methyl-3-(4-sulfobutyl) imidazolium bisulfate, and cholinium taurate,
will be evaluated. Additionally, critical parameters affecting the treatment process,
such as temperature, the ratio of ionic liquids to residue dose, concentration of ionic
liquids, and time taken, would also be discussed.
Keywords Lignocellulosic materials · Pretreatment · Ionic liquids · Bioethanol
I. Neme
Department of Chemical Engineering, College of Biological and Chemical Engineering, Addis
Ababa Science and Technology University, Addis Ababa, Ethiopia
C. Masi (*)
Department of Biotechnology, College of Biological and Chemical Engineering, Addis Ababa
Science and Technology University, Addis Ababa, Ethiopia
e-mail: chandran.chandran@aastu.edu.et
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021
J. Aravind et al. (eds.), Strategies and Tools for Pollutant Mitigation,
https://doi.org/10.1007/978-3-030-63575-6_3
49