The concept of integrated forest biorefineries(IFBRs) has gained significant interest.The prehydrolysis kraft(PHK) dissolving pulp production process is a suitable example of IFBR concept for the production of dissolv...The concept of integrated forest biorefineries(IFBRs) has gained significant interest.The prehydrolysis kraft(PHK) dissolving pulp production process is a suitable example of IFBR concept for the production of dissolving pulp and utilization of dissolved hemicelluloses,acetic acid,and lignin in the prehydrolysis liquor(PHL).This review paper highlights recent progress related to the recovery and utilization of dissolved organics(e.g.,hemicelluloses,acetic acid,and lignin) in the PHL of the PHK dissolving pulp production process.Integrated multi-step recovery and separation processes have been developed for this purpose to accommodate the complex nature of the PHL.Potential products,including xylan-based compounds,acetic acid,and lignin,are also discussed in detail.展开更多
Paper products such as corrugated paperboards are the most common green packaging materials, which are renewable, sustainable, recyclable and biodegradable. However, the plastic or metal straps used to secure the cart...Paper products such as corrugated paperboards are the most common green packaging materials, which are renewable, sustainable, recyclable and biodegradable. However, the plastic or metal straps used to secure the carton boxes are not so green. At the end of packaging, the carton boxes can be recycled, but the plastic/metal straps have to be sorted out for disposal separately. This review focuses on: 1) the global trend of green packaging;2) conventional plastic/metal strapping materials for carton boxes;3) conventional market pulp baling with steel wire as the tying materials;4) cellulose fiber-based materials for strapping market pulp bales and carton boxes. New generation of cellulose paper straps are being developed for more challenging applications with superior strength properties and repulpability.展开更多
Slime formation on paper machines is a critical issue that can substantially impact the quantity and quality of paper production.This problem is caused by the growth of an abundant and diverse amount of bacteria.Throu...Slime formation on paper machines is a critical issue that can substantially impact the quantity and quality of paper production.This problem is caused by the growth of an abundant and diverse amount of bacteria.Through the application of emulsion polymerase chain reaction(emPCR),the bacterial diversity was analyzed on paper machines and more operational taxonomic units(OTUs)were obtained.Eleven types of bacterial phyla were found that have been previously identified,including Proteobacteria(α-,β-,γ-,ε-,andφ-),Bacteroidetes,Firmicutes,Cyanobacteria,Verrucomicrobia,Actinobacteria,Spirochaetes,Chloroflexi,Deinococcus-Thermus,and Armatimonadetes.Furthermore,for the first time,there were representatives of the phyla Lentisphaerae found on paper machines.This study revealed the wide bacterial diversities of slime found on paper machines in China,which was also similar to other industrial processes.展开更多
Eucalyptus chemithermomechanical pulp(CTMP)was modified with the white-rot fungus 19-6 in a stationary culture condition.Different factors that influence the effect of white-rot fungus treatment,including additional n...Eucalyptus chemithermomechanical pulp(CTMP)was modified with the white-rot fungus 19-6 in a stationary culture condition.Different factors that influence the effect of white-rot fungus treatment,including additional nutrition,pH value,temperature,treatment time and oxygen input were investigated.The results show that the energy consumption of post refining of CTMP treated by white-rot fungus 19-6 was lower than that of untreated pulp and the strength properties also obviously improved.At a freeness level of about 330 mL,compared to the untreated pulp,the tensile index,tear index and internal bonding strength increased by 21.3%,27.4% and 33.1%,respectively.Unfortunately,the treatment with white-rot fungus substantially decreased all optical properties except for opacity,which was essentially unchanged.Brightness and light scatter-ing coefficient were reduced to as much as 25%and 21%compared to the untreated pulps.However,after a tow-stage“Na_(2)S_(2)O_(4)-H_(2)O_(2)”bleaching,the final brightness can reach 70.3%ISO,which is similar to that of the untreated CTMP.展开更多
The discharge of large amounts of dye-containing wastewater seriously threats the environment.Adsorbents have been adopted to remove these dyes present in the wastewater.However,the high adsorption capacity,predominan...The discharge of large amounts of dye-containing wastewater seriously threats the environment.Adsorbents have been adopted to remove these dyes present in the wastewater.However,the high adsorption capacity,predominant pH-responsibility,and excellent recyclability are three challenges to the development of efficient adsorbents.The poly(acryloxyethyl trimethylammonium chloride)-graft-dialdehyde cellulose nanocrystals were synthesized in our work.Subsequently,the cationic dialdehyde cellulose nanocrystal cross-linked chitosan nanocomposite foam was fabricated via freeze-drying of the hydrogel.Under the optimal ratio of the cationic dialdehyde cellulose nanocrystal/chitosan(w/w)of 12/100,the resultant foam(Foam-12)possesses excellent absorption properties,such as high porosity,high content of active sites,strong acid resistance,and high amorphous region.Then,Foam-12 was applied as an eco-friendly adsorbent to remove acid red 134(a representative of anionic dyes)from aqueous solutions.The maximum dye adsorption capacity of 1238.1 mg∙g^(‒1) is achieved under the conditions of 20 mg∙L‒1 adsorbents,100 mg∙L^(‒1) dye,pH 3.5,24 h,and 25℃.The dominant adsorption mechanism for the anionic dye adsorption is electrostatic attraction,and Foam-12 can effectively adsorb acid red 134 at pH 2.5–5.5 and be desorbed at pH 8.Its easy recovery and good reusability are verified by the repeated acid adsorption–alkaline desorption experiments.展开更多
文摘The concept of integrated forest biorefineries(IFBRs) has gained significant interest.The prehydrolysis kraft(PHK) dissolving pulp production process is a suitable example of IFBR concept for the production of dissolving pulp and utilization of dissolved hemicelluloses,acetic acid,and lignin in the prehydrolysis liquor(PHL).This review paper highlights recent progress related to the recovery and utilization of dissolved organics(e.g.,hemicelluloses,acetic acid,and lignin) in the PHL of the PHK dissolving pulp production process.Integrated multi-step recovery and separation processes have been developed for this purpose to accommodate the complex nature of the PHL.Potential products,including xylan-based compounds,acetic acid,and lignin,are also discussed in detail.
文摘Paper products such as corrugated paperboards are the most common green packaging materials, which are renewable, sustainable, recyclable and biodegradable. However, the plastic or metal straps used to secure the carton boxes are not so green. At the end of packaging, the carton boxes can be recycled, but the plastic/metal straps have to be sorted out for disposal separately. This review focuses on: 1) the global trend of green packaging;2) conventional plastic/metal strapping materials for carton boxes;3) conventional market pulp baling with steel wire as the tying materials;4) cellulose fiber-based materials for strapping market pulp bales and carton boxes. New generation of cellulose paper straps are being developed for more challenging applications with superior strength properties and repulpability.
基金supported by grants from the Major Research Project of the Natural Science Foundation of Jiangsu Higher Education Institutions(No.14KJA53002)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Slime formation on paper machines is a critical issue that can substantially impact the quantity and quality of paper production.This problem is caused by the growth of an abundant and diverse amount of bacteria.Through the application of emulsion polymerase chain reaction(emPCR),the bacterial diversity was analyzed on paper machines and more operational taxonomic units(OTUs)were obtained.Eleven types of bacterial phyla were found that have been previously identified,including Proteobacteria(α-,β-,γ-,ε-,andφ-),Bacteroidetes,Firmicutes,Cyanobacteria,Verrucomicrobia,Actinobacteria,Spirochaetes,Chloroflexi,Deinococcus-Thermus,and Armatimonadetes.Furthermore,for the first time,there were representatives of the phyla Lentisphaerae found on paper machines.This study revealed the wide bacterial diversities of slime found on paper machines in China,which was also similar to other industrial processes.
基金This work was supported by the National Basic Research Program of China(No 2006 CB 708614).
文摘Eucalyptus chemithermomechanical pulp(CTMP)was modified with the white-rot fungus 19-6 in a stationary culture condition.Different factors that influence the effect of white-rot fungus treatment,including additional nutrition,pH value,temperature,treatment time and oxygen input were investigated.The results show that the energy consumption of post refining of CTMP treated by white-rot fungus 19-6 was lower than that of untreated pulp and the strength properties also obviously improved.At a freeness level of about 330 mL,compared to the untreated pulp,the tensile index,tear index and internal bonding strength increased by 21.3%,27.4% and 33.1%,respectively.Unfortunately,the treatment with white-rot fungus substantially decreased all optical properties except for opacity,which was essentially unchanged.Brightness and light scatter-ing coefficient were reduced to as much as 25%and 21%compared to the untreated pulps.However,after a tow-stage“Na_(2)S_(2)O_(4)-H_(2)O_(2)”bleaching,the final brightness can reach 70.3%ISO,which is similar to that of the untreated CTMP.
基金This work was supported by the Natural Science Advance Research Foundation of Shaanxi University of Science and Technology(Grant No.2020XSGG-07)the Key Research and Development Program of Shaanxi Province(Grant No.2022GY-278)the Natural Science Basic Research Program of Shannxi(Program No.2023-JC-YB-104).
文摘The discharge of large amounts of dye-containing wastewater seriously threats the environment.Adsorbents have been adopted to remove these dyes present in the wastewater.However,the high adsorption capacity,predominant pH-responsibility,and excellent recyclability are three challenges to the development of efficient adsorbents.The poly(acryloxyethyl trimethylammonium chloride)-graft-dialdehyde cellulose nanocrystals were synthesized in our work.Subsequently,the cationic dialdehyde cellulose nanocrystal cross-linked chitosan nanocomposite foam was fabricated via freeze-drying of the hydrogel.Under the optimal ratio of the cationic dialdehyde cellulose nanocrystal/chitosan(w/w)of 12/100,the resultant foam(Foam-12)possesses excellent absorption properties,such as high porosity,high content of active sites,strong acid resistance,and high amorphous region.Then,Foam-12 was applied as an eco-friendly adsorbent to remove acid red 134(a representative of anionic dyes)from aqueous solutions.The maximum dye adsorption capacity of 1238.1 mg∙g^(‒1) is achieved under the conditions of 20 mg∙L‒1 adsorbents,100 mg∙L^(‒1) dye,pH 3.5,24 h,and 25℃.The dominant adsorption mechanism for the anionic dye adsorption is electrostatic attraction,and Foam-12 can effectively adsorb acid red 134 at pH 2.5–5.5 and be desorbed at pH 8.Its easy recovery and good reusability are verified by the repeated acid adsorption–alkaline desorption experiments.
