Comparative Study of the Preparation of Reducing Sugars Hydrolyzed from High-Lignin Lignocellulose Pretreated with Ionic Liquid, Alkaline Solution and Their Combination

Abstract

Abstract. The ionic liquid [MMIM][DMP] was synthesized from the reactants methyl imidazole [MIM] and trimethylphosphate [TMP] and verified using 1 HNMR and FTIR. Coconut coir dust was pretreated with a 1% alkaline solution. Its crystalline structure increased significantly due to the dissolution of lignin and hemicelluloses under alkaline conditions, exposing the cellulose. After NaOH and IL were employed, the XRD showed that peak (002) decreased significantly and peak (101) almost vanished. This significant decrease in crystallinity was related to the alteration of the substrate from the cellulose I structure to the cellulose II structure. The pretreated substrates were hydrolyzed to convert them to reducing sugars by pure cellulase and xylanase, and the reaction was conducted at 60°C, pH 3, for 12 or 48 hours. The yields of sugar hydrolyzed from untreated and NaOH-pretreated substrates were 0.07 and 0.12 g sugar/g lignocellulose, respectively. Pretreatment with IL or the combination of NaOH+IL resulted in yields of reducing sugars of 0.11 and 0.13 g/g, respectively. These findings showed that IL pretreatment of the high-lignin lignocellulose is a new prospect for the economical manufacture of reducing sugars and bioethanol in the coming years.

Synergistic Effect of Two Type Cellulase Immobilized on Chitosan Microparticle as Biocatalyst for Coconut Husk Hydrolysis

“…There is no report for application on coconut husk. Coconut husks are treated as waste in Indonesia even though it contains 17.73% hemicellulose and 26.73% cellulose [24].…”

The product of interaction of elemental sulfur and dimethylphosphate 1,3-dimethylimidazolium is a new green initiator of formaldehyde polymerization

“…The proton signal of the equivalent methyl groups of the dimethyl phosphate residue splits into a doublet with a chemical shift of 3.31 ppm as a result of spin-spin interaction with the 31 P core. All the described signals practically do not change their position in comparison with the initial 1,3-dimethylimidazolium dimethylphosphate (19). The 4.59 ppm singlet corresponds to the product of attaching a single formaldehyde molecule to the Me 2 PO 4 S − n initiating system, since otherwise it would have been split into a multiplet due to the spin-spin interaction realized in the spin system - CH 2 -O-CH 2or as a result of the spin-spin interaction with the 31 P core, if the oligosulfide chain was not part of the initiating anion.…”

Kinetics Study the Decomposition of the Cellulose into Cellulose Nanocrystals by Hydrothermal with Hydrochloric Acid Catalyst

“…12 CNCs shown maximum crystal diffraction peaks located at the angle 2θ = 22.6 o ± 0.2 with 002 lattice planes, which shows crystalline cellulose I. 19,20 At an angle 2θ = 35 o all diffraction pattern still shows a peak crystalline cellulose are low, this indicates that hydrochloric acid catalyst capable of persevering region crystals that are at the peak of the weak areas. 19 Overall CNCs shows the crystallite size below 7.83 nm, this proves that the hydrolysis using acid catalysts are applied can reduce the size of crystalline cellulose.…”