4.2.6 1-Methyl-3-(4-Sulfobutyl)Imidazolium Bisulfate
(HSO 3 -BMIM-HSO 4 )
It has the highest catalytic performance and was used to further evaluate the effects
of ionic liquid concentration, reaction time, and temperature on the conversion rate
of wheat straw when compared with IL of BMIM-Cl and BMIM-HSO 4 . This
indicates that the HSO 4 anion is more efficient than the Cl anion at dissolving and
converting wheat straw. The conversion rates of wheat straw catalyzed by BMIMHSO 4 was 85.8% (Guan et al. 2018).
4.2.7 Cholinium Taurate (Ch-Tau) ILs
Taurine is one of the sulfur-containing amino acids but does not form proteins. It is
produced from renewable materials and, in natural form, can be found in high
concentrations in skeletal and cardiac muscle and brain tissue. The acids intended
for this IL production contains the alkylated derivatives of glycine (sarcosine and N,
N-dimethyl glycine), nutritional ingredient (taurine), important bio-based platform
compounds (levulinic acid and 2-furoic acid), and inorganic acids (H 2 SO 4 and
H 3 PO 4 ). The pretreatment of wheat straw with Ch-Tau ILs at 90
C obtained
68.8% of lignin, which was separated from wheat straw (Ren et al. 2016) (Table 3.4).
5 Conclusion
Ionic liquid pretreatment provides a potentially cost-effective way designed for
bioethanol production from agricultural residue, due to less usage and easy recycling
of ILs. Out of the various types of ionic liquids, 1-butyl-3-methylimidazolium
chloride (Bmim-Cl) and 1-butyl-3-methylimidazolium thiocyanate (Bmim-SCN)
have better cellulose solubility characteristic. However, the ionic liquids involving
Cl- and SCN- are corrosive and toxic and did not permit an absolute dissolution of
wheat straw. EMIM-DEP and BMIM-HSO 4 are among the best cellulose solvents in
terms of solubility characterization and compatibility with hydrolytic enzymes.
Additionally, EMIM-DEP is easy to synthesize than BMIM-Cl ILs. Furthermore,
they are an environment-friendly ionic liquid. In terms of experiment conditions, for
all of IL variants, 150
C or more temperature is suitable for the pretreatment of
wheat straw. Regenerated cellulose of wheat straw hydrolyzed more easily than
being treated with water, and their enzymatic hydrolysis rates were improved
excellently.
3 Pretreatment of Wheat Straw Using Ionic Liquids for Bioethanol Production. . .
59
(HSO 3 -BMIM-HSO 4 )
It has the highest catalytic performance and was used to further evaluate the effects
of ionic liquid concentration, reaction time, and temperature on the conversion rate
of wheat straw when compared with IL of BMIM-Cl and BMIM-HSO 4 . This
indicates that the HSO 4 anion is more efficient than the Cl anion at dissolving and
converting wheat straw. The conversion rates of wheat straw catalyzed by BMIMHSO 4 was 85.8% (Guan et al. 2018).
4.2.7 Cholinium Taurate (Ch-Tau) ILs
Taurine is one of the sulfur-containing amino acids but does not form proteins. It is
produced from renewable materials and, in natural form, can be found in high
concentrations in skeletal and cardiac muscle and brain tissue. The acids intended
for this IL production contains the alkylated derivatives of glycine (sarcosine and N,
N-dimethyl glycine), nutritional ingredient (taurine), important bio-based platform
compounds (levulinic acid and 2-furoic acid), and inorganic acids (H 2 SO 4 and
H 3 PO 4 ). The pretreatment of wheat straw with Ch-Tau ILs at 90
C obtained
68.8% of lignin, which was separated from wheat straw (Ren et al. 2016) (Table 3.4).
5 Conclusion
Ionic liquid pretreatment provides a potentially cost-effective way designed for
bioethanol production from agricultural residue, due to less usage and easy recycling
of ILs. Out of the various types of ionic liquids, 1-butyl-3-methylimidazolium
chloride (Bmim-Cl) and 1-butyl-3-methylimidazolium thiocyanate (Bmim-SCN)
have better cellulose solubility characteristic. However, the ionic liquids involving
Cl- and SCN- are corrosive and toxic and did not permit an absolute dissolution of
wheat straw. EMIM-DEP and BMIM-HSO 4 are among the best cellulose solvents in
terms of solubility characterization and compatibility with hydrolytic enzymes.
Additionally, EMIM-DEP is easy to synthesize than BMIM-Cl ILs. Furthermore,
they are an environment-friendly ionic liquid. In terms of experiment conditions, for
all of IL variants, 150
C or more temperature is suitable for the pretreatment of
wheat straw. Regenerated cellulose of wheat straw hydrolyzed more easily than
being treated with water, and their enzymatic hydrolysis rates were improved
excellently.
3 Pretreatment of Wheat Straw Using Ionic Liquids for Bioethanol Production. . .
59