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John N Saddler - One of the best experts on this subject based on the ideXlab platform.

  • use of endoglucanase and accessory enzymes to facilitate Mechanical Pulp nanofibrillation
    ACS Sustainable Chemistry & Engineering, 2021
    Co-Authors: Xushen Han, Vinay Khatri, Hale Oguzlu, Masatsugu Takada, Jungang Jiang, Feng Jiang, Jie Bao, John N Saddler
    Abstract:

    Although selective enzyme treatments have been used to successfully fibrillate chemical Pulps, high lignin-containing Mechanical Pulps have proven to be more recalcitrant. When a bleached chemi-the...

  • use of endoglucanase and accessory enzymes to facilitate Mechanical Pulp nanofibrillation
    ACS Sustainable Chemistry & Engineering, 2021
    Co-Authors: Xushen Han, Vinay Khatri, Hale Oguzlu, Masatsugu Takada, Jungang Jiang, Feng Jiang, Jie Bao, John N Saddler
    Abstract:

    Although selective enzyme treatments have been used to successfully fibrillate chemical Pulps, high lignin-containing Mechanical Pulps have proven to be more recalcitrant. When a bleached chemi-thermoMechanical Pulp (BCTMP) was sulfonated prior to enzymatic treatment, relatively good fibrillation was achieved, although some Pulp hydrolysis occurred after 6 h hydrolysis when using a commercial cellulase enzyme preparation (Cellic CTec 3). To try to minimize Pulp losses, various enzyme cocktails, including endoglucanase (EG), xylanase, mannanase, and lytic polysaccharide monooxygenase (LPMO), were assessed for their ability to enhance fibrillation while minimizing cellulose hydrolysis. It was apparent that the yield as well as the zeta potential of the lignin-containing cellulose nanofibrils increased with enzyme treatment. This was likely due to an increase in surface charge and a decrease in particle size after LPMO and hemicellulase treatments, respectively. When carbohydrate-binding modules (CBMs) were used to quantify fiber changes, it was apparent that sulfonation had increased the accessibility of enzymes, while the combined action of the hemicellulases and LPMO increased EG accessibility to the less-ordered regions of the Mechanical Pulp, resulting in enhanced fibrillation. This work described, for the first time, the synergistic action of EG and various accessory enzymes enhancing Mechanical Pulp nanofibrillation.

  • comparing a deep eutectic solvent des to a hydrotrope for their ability to enhance the fractionation and enzymatic hydrolysis of willow and corn stover
    Sustainable Energy and Fuels, 2019
    Co-Authors: Richard P Chandra, Yanliang Song, Xu Zhang, Tianwei Tan, John N Saddler
    Abstract:

    This work compared the effectiveness of a deep eutectic solvent system, lactic acid:betaine (DES), to a hydrotrope, p-toluenesulfonic acid (p-TsOH), for their ability to fractionate lignin under mild conditions after a Mechanical pretreatment process that was applied to corn stover and willow biomass. The hydrotrope and DES were assessed based on their ability to recover carbohydrates, selectively remove lignin, affect the lignin structure and enhance the subsequent enzymatic hydrolysis of the residual cellulose. The hydrotrope and DES both exhibited the ability to remove lignin. However, the DES treatment removed lignin with greater selectivity and allowed increased cellulose and hemicellulose recovery at a pretreatment temperature of 140 °C. Despite compromising hemicellulose recovery, p-TsOH could efficiently remove 51–96% lignin at relatively low temperatures (50–80 °C). The lignins isolated from both treatments were characterized for their molecular weight and the amounts and types of hydroxyl groups using gel permeation chromatography and 31P NMR spectroscopy. It was apparent that the lignin removed using the hydrotropic treatment at 50 °C had similar molecular weight and functionality to enzymatic-mild acidolysis lignin (EMAL) isolated from the corresponding untreated corn stover and willow Mechanical Pulp substrates.

  • the effect of initial pore volume and lignin content on the enzymatic hydrolysis of softwoods
    Bioresource Technology, 1998
    Co-Authors: Caitriona A Mooney, Shawn D Mansfield, Maria G Touhy, John N Saddler
    Abstract:

    Four Douglas-fir Pulps, a refiner Mechanical Pulp (RMP), sulphonated RMP, delignified RMP and a kraft Pulp were used to determine whether the lignin content and initial pore volume affected cellulase adsorption and substrate hydrolysis. When compared on the basis of lignin content, it was apparent from the cellulase treatment of the sulphonated RMP that the proportion of lignin did not affect enzyme adsorption when the fibres were sufficiently swollen. However, it was observed that the initial adsorption of cellulase does not always translate to fast and complete hydrolysis. Pore volume data revealed that although modification of lignin resulted in a dramatically increased fibre saturation point the median pore width was not increased accordingly. In contrast, the delignified RMP had a higher median pore width and was hydrolyzed more completely, suggesting that steric hindrance from the residual lignin may be the rate limiting characteristic in this situation. Hydrolysis of the kraft Pulp indicated that the larger average particle size of this substrate might have been an inhibiting factor, since it was hydrolyzed more slowly than the delignified RMP despite having a higher median pore width and lower lignin content.

Michelle Ricard - One of the best experts on this subject based on the ideXlab platform.

  • purified pectinase lowers cationic demand in peroxide bleached Mechanical Pulp
    Enzyme and Microbial Technology, 2004
    Co-Authors: Michelle Ricard, Ian D Reid
    Abstract:

    Pectinase, purified from the commercial enzyme mixture Novozym 863 by affinity chromatography, was able to lower the cationic demand of peroxide-bleached Mechanical Pulp. It was also able to enhance the ability of cationic polymers to increase fines and ash retention. A second purified pectinase, cloned polygalacturonase I from the fungus Aspergillus aculeatus, also produced these effects. However, when applied at the same pectinase activity, the crude pectinase increased retention more than the purified polygalacturonase. Apparently, other enzyme activities in Novozym 863 contribute to its effects on retention. This research expands our understanding of pectinase activity by proving that pectinase is responsible for both reducing cationic demand and improving the retention of peroxide-bleached thermoMechanical Pulps.

  • pectinase in papermaking solving retention problems in Mechanical Pulps bleached with hydrogen peroxide
    Enzyme and Microbial Technology, 2000
    Co-Authors: Ian D Reid, Michelle Ricard
    Abstract:

    Treatment with the enzyme pectinase has been reported to lower the cationic demand of thermoMechanical Pulp (TMP) bleached with alkaline peroxide in the laboratory. We have extended this discovery to bleached TMP produced industrially, and shown that commercial enzyme preparations can treat Pulp within 15 min at the temperature and pH values prevalent in paper mills. About half of the cationic demand in the bleached Pulp can be destroyed by pectinase. Dynamic drainage jar experiments show that the enzyme treatment improves the effectiveness of several cationic polymers to increase retention of fines and filler particles. It does not increase retention in the absence of retention aids or with nonionic polymers, and does not damage the strength properties of the Pulp. Pectinase could be easily incorporated into paper machine stock preparation systems to lower the charges of cationic retention aids needed in furnishes containing peroxide-bleached Mechanical Pulp.

Ian D Reid - One of the best experts on this subject based on the ideXlab platform.

  • purified pectinase lowers cationic demand in peroxide bleached Mechanical Pulp
    Enzyme and Microbial Technology, 2004
    Co-Authors: Michelle Ricard, Ian D Reid
    Abstract:

    Pectinase, purified from the commercial enzyme mixture Novozym 863 by affinity chromatography, was able to lower the cationic demand of peroxide-bleached Mechanical Pulp. It was also able to enhance the ability of cationic polymers to increase fines and ash retention. A second purified pectinase, cloned polygalacturonase I from the fungus Aspergillus aculeatus, also produced these effects. However, when applied at the same pectinase activity, the crude pectinase increased retention more than the purified polygalacturonase. Apparently, other enzyme activities in Novozym 863 contribute to its effects on retention. This research expands our understanding of pectinase activity by proving that pectinase is responsible for both reducing cationic demand and improving the retention of peroxide-bleached thermoMechanical Pulps.

  • pectinase in papermaking solving retention problems in Mechanical Pulps bleached with hydrogen peroxide
    Enzyme and Microbial Technology, 2000
    Co-Authors: Ian D Reid, Michelle Ricard
    Abstract:

    Treatment with the enzyme pectinase has been reported to lower the cationic demand of thermoMechanical Pulp (TMP) bleached with alkaline peroxide in the laboratory. We have extended this discovery to bleached TMP produced industrially, and shown that commercial enzyme preparations can treat Pulp within 15 min at the temperature and pH values prevalent in paper mills. About half of the cationic demand in the bleached Pulp can be destroyed by pectinase. Dynamic drainage jar experiments show that the enzyme treatment improves the effectiveness of several cationic polymers to increase retention of fines and filler particles. It does not increase retention in the absence of retention aids or with nonionic polymers, and does not damage the strength properties of the Pulp. Pectinase could be easily incorporated into paper machine stock preparation systems to lower the charges of cationic retention aids needed in furnishes containing peroxide-bleached Mechanical Pulp.

Xushen Han - One of the best experts on this subject based on the ideXlab platform.

  • use of endoglucanase and accessory enzymes to facilitate Mechanical Pulp nanofibrillation
    ACS Sustainable Chemistry & Engineering, 2021
    Co-Authors: Xushen Han, Vinay Khatri, Hale Oguzlu, Masatsugu Takada, Jungang Jiang, Feng Jiang, Jie Bao, John N Saddler
    Abstract:

    Although selective enzyme treatments have been used to successfully fibrillate chemical Pulps, high lignin-containing Mechanical Pulps have proven to be more recalcitrant. When a bleached chemi-thermoMechanical Pulp (BCTMP) was sulfonated prior to enzymatic treatment, relatively good fibrillation was achieved, although some Pulp hydrolysis occurred after 6 h hydrolysis when using a commercial cellulase enzyme preparation (Cellic CTec 3). To try to minimize Pulp losses, various enzyme cocktails, including endoglucanase (EG), xylanase, mannanase, and lytic polysaccharide monooxygenase (LPMO), were assessed for their ability to enhance fibrillation while minimizing cellulose hydrolysis. It was apparent that the yield as well as the zeta potential of the lignin-containing cellulose nanofibrils increased with enzyme treatment. This was likely due to an increase in surface charge and a decrease in particle size after LPMO and hemicellulase treatments, respectively. When carbohydrate-binding modules (CBMs) were used to quantify fiber changes, it was apparent that sulfonation had increased the accessibility of enzymes, while the combined action of the hemicellulases and LPMO increased EG accessibility to the less-ordered regions of the Mechanical Pulp, resulting in enhanced fibrillation. This work described, for the first time, the synergistic action of EG and various accessory enzymes enhancing Mechanical Pulp nanofibrillation.

  • use of endoglucanase and accessory enzymes to facilitate Mechanical Pulp nanofibrillation
    ACS Sustainable Chemistry & Engineering, 2021
    Co-Authors: Xushen Han, Vinay Khatri, Hale Oguzlu, Masatsugu Takada, Jungang Jiang, Feng Jiang, Jie Bao, John N Saddler
    Abstract:

    Although selective enzyme treatments have been used to successfully fibrillate chemical Pulps, high lignin-containing Mechanical Pulps have proven to be more recalcitrant. When a bleached chemi-the...

Fangfang Wang - One of the best experts on this subject based on the ideXlab platform.

  • determination of lignin concentration in bleaching effluent via coomassie brilliant blue g 250 method
    Bioresources, 2020
    Co-Authors: Fangfang Wang
    Abstract:

    Kraft Pulp and alkali peroxide Mechanical Pulp were prepared with aspen and wheat straw and bleached with chlorine dioxide, an alkali extraction strengthened by hydrogen peroxide, hydrogen peroxide, or peroxyacetic acid. Eight different bleaching effluents were obtained, and a Coomassie brilliant blue G-250 method was applied to determine the lignin content in each of the bleaching effluents. The visible light spectra indicated that the alkali-soluble lignin and the alkali bleaching effluent could increase the absorbance of Coomassie brilliant blue G-250 at 640 nm, but the acidic soluble lignin and the acidic bleaching effluent did not increase absorbance. Thus, the Coomassie brilliant blue G-250 method applied to alkali bleaching effluents but did not apply to acidic bleaching effluents. An analysis of the pH, particle size, zeta potential, and visible light spectra determination showed the Coomassie brilliant blue G-250 absorbed on lignin particles, which caused the absorbance increase at 640 nm. With the actual measured value of the lignin content obtained via the Klason lignin method, the relative error of the results obtained via the Coomassie brilliant blue G-250 method was less than or equal to 3.8%.

  • bioMechanical Pulping of corn stalk rind with a white rot fungus trametes hirsuta and the use of delignified corn stalk pith as a Pulp additive
    Bioresources, 2015
    Co-Authors: Fangfang Wang, Guihua Yang, Honglei Chen, Yuzhong Zhang, Peiji Gao, Jiachuan Chen, Feng Huang
    Abstract:

    Corn stalk rind (CSR) was treated with Trametes hirsuta lg-9 and then refined into Pulp. The biotreatment resulted in loss of paper strength and brightness, but energy consumption during refining (ECR) was reduced. Meanwhile, multiple linear regression was carried out, for which ECR served as the dependent variable, and the yield and infrared relative absorbance intensities at 3414 cm-1 and 1653 cm-1 of the biotreated CSR served as independent variables. Results showed that the determining parameters of the biotreated CSR may be used to predict the ECR. In this work, delignified corn stalk pith (CSP) was added to aspen alkaline hydrogen peroxide Mechanical Pulp (APMP). The CSP enhanced the strength properties of the aspen APMP and inhibited yellowing. The bioMechanical Pulping of CSR has the potential to produce a low-cost green Pulp, and the delignified CSP can serve as a Pulp additive.

  • BioMechanical Pulping of Corn Stalk Rind with a White Rot Fungus – Trametes hirsuta – and the Use of Delignified Corn Stalk Pith as a Pulp Additive
    North Carolina State University, 2015
    Co-Authors: Fangfang Wang, Guihua Yang, Honglei Chen, Yuzhong Zhang, Peiji Gao, Jiachuan Chen, Feng Huang
    Abstract:

    Corn stalk rind (CSR) was treated with Trametes hirsuta lg-9 and then refined into Pulp. The biotreatment resulted in loss of paper strength and brightness, but energy consumption during refining (ECR) was reduced. Meanwhile, multiple linear regression was carried out, for which ECR served as the dependent variable, and the yield and infrared relative absorbance intensities at 3414 cm-1 and 1653 cm-1 of the biotreated CSR served as independent variables. Results showed that the determining parameters of the biotreated CSR may be used to predict the ECR. In this work, delignified corn stalk pith (CSP) was added to aspen alkaline hydrogen peroxide Mechanical Pulp (APMP). The CSP enhanced the strength properties of the aspen APMP and inhibited yellowing. The bioMechanical Pulping of CSR has the potential to produce a low-cost green Pulp, and the delignified CSP can serve as a Pulp additive