Isolation and utilization of hemicellulose are important processes in the pulp mill-based biorefinery. Considering the potential end use of the hemicellulose,this study investigated the concentration of monomeric and ...Isolation and utilization of hemicellulose are important processes in the pulp mill-based biorefinery. Considering the potential end use of the hemicellulose,this study investigated the concentration of monomeric and oligomeric sugars in the hydrolysate derived from autohydrolysis of acacia wood and the obtainment of these sugars via ethanol precipitation. The rate of generation of monomers and oligomers increased dramatically with an increase of the temperature from 160℃ to 180℃. The maximum content of oligomers and total sugars was achieved under conditions of 180℃ and 10 min,170℃ and 85 min,respectively. Interestingly,the maximum yield of hemicellulose via ethanol precipitation was achieved in a much shorter time,compared with the maximum yield of oligomer from the hydrolysate by autohydrolysis. A 6. 66 g / L quantity of hemicellulose was obtained by intensifying the conditions of ethanol precipitation. The hemicellulose characteristics were analyzed by Fourier transform infrared,nuclear magnetic resonance,and ultraviolet spectroscopy,and the molecular weight was determined by gel permeation chromatography and thermal analysis.展开更多
The objective of this work is to systematically evaluate the performance of the hydrolysis-based kraft pulping process and associated pulp and black liquor characteristics.Acacia wood chips were auto-hydrolyzed under ...The objective of this work is to systematically evaluate the performance of the hydrolysis-based kraft pulping process and associated pulp and black liquor characteristics.Acacia wood chips were auto-hydrolyzed under various severities,then the hydrolyzed wood chips were kraft pulping.The results indicated that the yield of pulp significantly dropped with intensifying the auto-hydrolysis severity.Meanwhile,the removal rate of pentosan reached 98.6%in the screened pulp at the P-factor of 1000.The fiber length,fines and fiber crimp of the screened pulp were not affected by the auto-hydrolysis treatment.Auto-hydrolyzed pulps deteriorated fibrillation and beating response of the pulp in a refining process.However,fiber length and fines changed obviously after beating treatment.After auto-hydrolysis,the tensile index of the paper matrices decreased,some particle substances were found on the surface of the pulp fiber,and the solid and organic content of the black liquor were improved.展开更多
基金supported by the National Natural Science Foundation of China(31470603)the Natural Science Foundation of Liaoning Province(2015020592)+1 种基金the Liaoning BaiQ ian Wan Talents Program(20149210-64)the Open Fund of State Key Lab of Pulp and Paper Engineering of China(201449)
文摘Isolation and utilization of hemicellulose are important processes in the pulp mill-based biorefinery. Considering the potential end use of the hemicellulose,this study investigated the concentration of monomeric and oligomeric sugars in the hydrolysate derived from autohydrolysis of acacia wood and the obtainment of these sugars via ethanol precipitation. The rate of generation of monomers and oligomers increased dramatically with an increase of the temperature from 160℃ to 180℃. The maximum content of oligomers and total sugars was achieved under conditions of 180℃ and 10 min,170℃ and 85 min,respectively. Interestingly,the maximum yield of hemicellulose via ethanol precipitation was achieved in a much shorter time,compared with the maximum yield of oligomer from the hydrolysate by autohydrolysis. A 6. 66 g / L quantity of hemicellulose was obtained by intensifying the conditions of ethanol precipitation. The hemicellulose characteristics were analyzed by Fourier transform infrared,nuclear magnetic resonance,and ultraviolet spectroscopy,and the molecular weight was determined by gel permeation chromatography and thermal analysis.
基金supported by Natural Science Foundation of China(No.31971608)Natural Science Foundation of Liaoning Province(No.2019-ZD-0125)+1 种基金Liaoning Baiqianwan Talents Program(No.2019)Innovative Talents in Liaoning Uni-versities and Colleges(No.2020).
文摘The objective of this work is to systematically evaluate the performance of the hydrolysis-based kraft pulping process and associated pulp and black liquor characteristics.Acacia wood chips were auto-hydrolyzed under various severities,then the hydrolyzed wood chips were kraft pulping.The results indicated that the yield of pulp significantly dropped with intensifying the auto-hydrolysis severity.Meanwhile,the removal rate of pentosan reached 98.6%in the screened pulp at the P-factor of 1000.The fiber length,fines and fiber crimp of the screened pulp were not affected by the auto-hydrolysis treatment.Auto-hydrolyzed pulps deteriorated fibrillation and beating response of the pulp in a refining process.However,fiber length and fines changed obviously after beating treatment.After auto-hydrolysis,the tensile index of the paper matrices decreased,some particle substances were found on the surface of the pulp fiber,and the solid and organic content of the black liquor were improved.
