Production of lignosulfonate in NSSC-based biorefinery.
The spent liquor (SL) of a neutral sulfite semichemical (NSSC) pulping process contains a considerable amount of lignocelluloses and is treated in wastewater systems. The lignocelluloses, however, can be used for producing value-added products if they are isolated from the SL. In this article, solvent treatment (mixing acetone, ethanol, or isopropyl with SL) was used as a method for isolating lignosulfonate from SL. The maximum lignosulfonate removal was obtained via mixing isopropyl alcohol with SL at the weight ratio of 20/80, room temperature, and 5.7 pH. The results also showed that the molecular weight and anionic charge density of the precipitates were in the range of 5,000-70,000 g/mol and 0.2-1.8 meq/g, respectively. Based on these results, a process was proposed for isolating lignosulfonate from SL and converting the NSSC process to an NSSC-based biorefinery.
Dept. of Chemical Engineering and Natural Resources Management Faculty, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, P7B 5E1, Canada.
Dmitry
D
Tarasov
Dept. of Chemical Engineering and Natural Resources Management Faculty, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, P7B 5E1, Canada.
Mathew
M
Leitch
Dept. of Chemical Engineering and Natural Resources Management Faculty, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, P7B 5E1, Canada.
Pedram
P
Fatehi
D007220:Industrial Waste / Q000032:analysis*; D008031:Lignin / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D008970:Molecular Weight; D012997:Solvents; D013447:Sulfites / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*
D007220:Industrial Waste; D008031:Lignin; D012997:Solvents; D013447:Sulfites; D062065:Wastewater; C036909:lignocellulose; C001545:lignosulfuric acid
biorefinery; charge density; hemicelluloses; lignosulfonate; molecular weight; solvent extraction