Residual-lignin-endowed molded pulp lunchbox with a sustained wet support strength

Nanocellulose was extracted from short bast fibers, from hemp (Cannabis sativa L.) plants harvested at seed maturity, non-retted, and mechanically decorticated in a defibering apparatus, giving non-aligned fibers. A chemical pretreatment with NaOH and HCl allowed the removal of most of the non-cellulosic components of the fibers. No bleaching was performed. The chemically pretreated fibers were then refined in a beater and treated with a cellulase enzyme, followed by mechanical defibrillation in an ultrafine friction grinder. The fibers were characterized by microscopy, infrared spectroscopy, thermogravimetric analysis and X-ray diffraction after each step of the process to understand the evolution of their morphology and composition. The obtained nanocellulose suspension was composed of short nanofibrils with widths of 5–12 nm, stacks of nanofibrils with widths of 20–200 nm, and some larger fibers. The crystallinity index was found to increase from 74% for the raw fibers to 80% for the nanocellulose. The nanocellulose retained a yellowish color, indicating the presence of some residual lignin. The properties of the nanopaper prepared with the hemp nanocellulose were similar to those of nanopapers prepared with wood pulp-derived rod-like nanofibrils.

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Understanding the effects of different residual lignin fractions in acid-pretreated bamboo residues on its enzymatic digestibility

Biotechnology for Biofuels ◽

10.1186/s13068-021-01994-y ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Wenqian Lin ◽

Jinlai Yang ◽

Yayue Zheng ◽

Caoxing Huang ◽

Qiang Yong

Keyword(s):

Enzymatic Hydrolysis ◽

Negative Impact ◽

Dilute Acid Pretreatment ◽

Residual Lignin ◽

Dilute Acid ◽

Enzymatic Digestibility ◽

Acid Pretreatment ◽

Organic Reagents ◽

Milled Wood Lignin ◽

Affinity Constants

Abstract Background During the dilute acid pretreatment process, the resulting pseudo-lignin and lignin droplets deposited on the surface of lignocellulose and inhibit the enzymatic digestibility of cellulose in lignocellulose. However, how these lignins interact with cellulase enzymes and then affect enzymatic hydrolysis is still unknown. In this work, different fractions of surface lignin (SL) obtained from dilute acid-pretreated bamboo residues (DAP-BR) were extracted by various organic reagents and the residual lignin in extracted DAP-BR was obtained by the milled wood lignin (MWL) method. All of the lignin fractions obtained from DAP-BR were used to investigate the mechanism for interaction between lignin and cellulase using surface plasmon resonance (SPR) technology to understand how they affect enzymatic hydrolysis Results The results showed that removing surface lignin significantly decreased the yield for enzymatic hydrolysis DAP-BR from 36.5% to 18.6%. The addition of MWL samples to Avicel inhibited its enzymatic hydrolysis, while different SL samples showed slight increases in enzymatic digestibility. Due to the higher molecular weight and hydrophobicity of MWL samples versus SL samples, a stronger affinity for MWL (KD = 6.8–24.7 nM) was found versus that of SL (KD = 39.4–52.6 nM) by SPR analysis. The affinity constants of all tested lignins exhibited good correlations (r > 0.6) with the effects on enzymatic digestibility of extracted DAP-BR and Avicel. Conclusions This work revealed that the surface lignin on DAP-BR is necessary for maintaining enzyme digestibility levels, and its removal has a negative impact on substrate digestibility.

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Enabled Cellulose Nanopaper with Outstanding Water Stability and Wet Strength via Activated Residual Lignin as a Reinforcement

Green Chemistry ◽

10.1039/d1gc03906g ◽

2021 ◽

Author(s):

jinlong wang ◽

Wei Chen ◽

Tengteng Dong ◽

Haiqi Wang ◽

Shurun Si ◽

...

Keyword(s):

Hydrogen Bonding ◽

Plant Cell ◽

Cell Walls ◽

Water Stability ◽

Plant Cell Walls ◽

Residual Lignin ◽

Wet Strength ◽

Cellulose Nanopaper

Due to water-sensitive hydrogen bonding, uncontrolled deformation and mechanical decay of cellulose nanopaper (CNP) caused by water remain challenging. Inspired by plant cell walls and bonding strengthening, a strategy is...

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Renewable diesel via hydrothermal liquefaction of oleaginous yeast and residual lignin from bioconversion of corn stover

Applied Energy ◽

10.1016/j.apenergy.2018.09.115 ◽

2019 ◽

Vol 233-234 ◽

pp. 840-853 ◽

Cited By ~ 10

Author(s):

James R. Collett ◽

Justin M. Billing ◽

Pimphan A. Meyer ◽

Andrew J. Schmidt ◽

A. Brook Remington ◽

...

Keyword(s):

Corn Stover ◽

Oleaginous Yeast ◽

Hydrothermal Liquefaction ◽

Residual Lignin ◽

Renewable Diesel

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Investigation of interaction between cellulase and residual lignin fractions in acid-pretreated bamboo residues and their effect on enzymatic digestibility

10.21203/rs.3.rs-371092/v1 ◽

2021 ◽

Author(s):

Wenqian Lin ◽

Jinlai Yang ◽

Yayue Zheng ◽

Caoxing Huang ◽

Qiang Yong

Keyword(s):

Enzymatic Hydrolysis ◽

Negative Impact ◽

Interaction Mechanism ◽

Dilute Acid Pretreatment ◽

Affinity Constant ◽

Residual Lignin ◽

Dilute Acid ◽

Enzymatic Digestibility ◽

Acid Pretreatment ◽

Hydrolysis Of

Abstract Background: During dilute acid pretreatment, pseudo lignin and lignin form droplets which deposit on the surface of lignocellulose, and further inhibit its enzymatic hydrolysis. However, how this lignin interacts with cellulase enzymes and then affects enzymatic hydrolysis is still unknown. In this work, different fractions of surface lignin (SL) obtained from dilute acid pretreated bamboo residues (DAP-BR) were extracted by various organic reagents and the residual lignin in extracted DAP-BR was obtained by milled wood lignin (MWL) method. All the obtained lignin fractions from DAP-BR were used to investigate the interaction mechanism between lignin and cellulase using surface plasmon resonance (SPR) technology in order to understand how they affect enzymatic hydrolysisResults: Results showed that removing surface lignin significantly decrease the enzymatic hydrolysis of DAP-BR from 36.5% to 18.6%. The addition of MWL samples to Avicel decreased enzymatic hydrolysis of Avicel, while different SL samples showed a slight increase to its enzymatic digestibility. Due to the higher molecular weight and hydrophobicity of MWL samples versus the SL samples, stronger affinity for MWL (KD = 6.8-24.7 nM) was found versus that of SL (KD = 39.4-52.6 nM) by SPR analysis. The affinity constant of all tested lignin had good correlations (R2>0.6) with their effects on enzymatic digestibility of extracted DAP-BR and Avicel.Conclusions: This work reveals that the surface lignin on DAP-BR is necessary towards maintaining enzyme digestibility levels, and its removal has a negative impact on the substrate’s digestibility.

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Structural Micro-analysis of Residual Lignin in Pulp by Pyrolysis-GC Mass-spectrometry

JAPAN TAPPI JOURNAL ◽

10.2524/jtappij.63.959 ◽

2009 ◽

Vol 63 (8) ◽

pp. 959-970 ◽

Cited By ~ 4

Author(s):

Ai Hasumi ◽

Akiko Nakagawa ◽

Mitsuko Homma ◽

Hiroshi Ohi ◽

Keiichi Nakamata

Keyword(s):

Mass Spectrometry ◽

Residual Lignin ◽

Micro Analysis

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Study of Regularities and Optimization of the Process of Fir Wood Peroxide Delignification in the Medium of “Acetic Acid – Water” in the Presence of Sulfuric Acid Catalyst

Journal of Siberian Federal University Chemistry ◽

10.17516/1998-2836-0154 ◽

2019 ◽

pp. 590-603

Author(s):

Olga V. Yatsenkova ◽

Andrei M. Skripnikov ◽

Boris N. Kuznetsov

Keyword(s):

Acetic Acid ◽

Lignin Content ◽

Reaction Medium ◽

Acid Catalyst ◽

Acid Water ◽

High Yield ◽

Process Conditions ◽

Residual Lignin ◽

Acetic Acid Water ◽

Peroxide Delignification

The work describes a one-stage method of cellulose obtaining from fir wood based on peroxide delignification of wood under mild conditions (100 °C, atmospheric pressure) in the presence of acetic acid, water and catalyst of 2% wt. H2SO4. The possibility of obtaining cellulose with a residual lignin content <1% wt. at a low concentration of hydrogen peroxide (3% wt.) in the reaction medium was established. The optimal concentrations of reagents (Н2О2 – 3% wt., CH3COOH – 38.9% wt.) and the duration of the process (4 h) were determined by experimental and calculation methods. This conditions provide a high yield of cellulose product (≥45% wt.) with a low content of residual lignin (<1% wt.). The composition and structure of fir cellulose was studied by chemical analysis and by FTIR and SEM methods. The cellulosic product which was obtained in optimal process conditions is high-quality cellulose

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Characterization of autohydrolysis aspen (P. tremuloides) lignins. Part 4. Residual autohydrolysis lignin

Canadian Journal of Chemistry ◽

10.1139/v79-422 ◽

1979 ◽

Vol 57 (19) ◽

pp. 2612-2616 ◽

Cited By ~ 14

Author(s):

Morris Wayman ◽

Miranda G. S. Chua

Keyword(s):

Enzymatic Hydrolysis ◽

Time Varying ◽

Residual Lignin ◽

Aspen Wood ◽

Milled Wood Lignin ◽

Wood Meal ◽

Nitrobenzene Oxidation ◽

Infrared Studies ◽

Lignocellulosic Residue

Lignocellulosic residue remaining after autohydrolysis of extractive-free aspen wood meal at 195 °C for periods of time varying from 5 to 120 min followed by extraction with 90% dioxane was subjected to enzymatic hydrolysis to obtain residual lignin. Infrared studies indicated that in the early stages of autohydrolysis residual lignin resembles protolignin, but as autohydrolysis proceeds it changes to resemble more and more the extracted lignin. Residual lignin was found to be higher in carbon but lower in hydrogen and oxygen than aspen milled wood lignin. The methoxyl content was also lower than the reference lignin. From alkaline nitrobenzene oxidation, residual lignin is seen to become more condensed with increasing autohydrolysis time. The insolubility of residual lignin is attributed to the existence of strong bonds between this lignin and carbohydrate.

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