scholarly journals Optimization of Lignin Recovery from the Pre-Hydrolysate of Kraft-Based Dissolving Pulp Production Processes

2021 ◽  
Vol 11 (1) ◽  
pp. 454
Author(s):  
Adil Mazar ◽  
Naceur Jemaa ◽  
Waleed Wafa Al Dajani ◽  
Mariya Marinova ◽  
Michel Perrier
Keyword(s):  
Molecular Weight ◽  
Lignin Content ◽  
Sulfuric Acid Concentration ◽  
Dissolving Pulp ◽  
Potential Candidate ◽  
Lignin Extraction ◽  
Dissolved Organic Matters ◽  
Lignin Recovery ◽  
Total Lignin ◽  
Total Lignin Content

A pre-hydrolysate is an aqueous stream obtained during the production of hardwood kraft dissolving pulp. It is rich in sugars and contains dissolved organic matters. The purpose of this study is to investigate the optimization of lignin recovery from wood pre-hydrolysates and to characterize the extracted lignin. The optimal conditions for lignin extraction have been determined to be (a) a filtration temperature of 40 °C, (b) a sulfuric acid concentration of 8.5 kg·m−3, and (c) a coagulation time of 180 min. Using these conditions, high filtration rates have been obtained and the extracted lignin has a low content of impurities (8.3%), a low molecular weight (1270 Da), and a very low polydispersity (Mw/Mn = 1.22). Compared to kraft lignin, the pre-hydrolysate lignin has a much lower molecular weight and could be a potential candidate for niche applications. A high lignin recovery rate is possible (52% of the total lignin content in the pre-hydrolysate).

scholarly journals Hypolignification: A Decisive Factor in the Development of Hyperhydricity

Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2625
Author(s):  
Nurashikin Kemat ◽  
Richard G. F. Visser ◽  
Frans A. Krens
Keyword(s):  
Cell Wall ◽  
Lignin Content ◽  
Coumaric Acid ◽  
Wild Type ◽  
Higher Plant ◽  
Gene Coding ◽  
Phenylpropanoid Biosynthesis ◽  
Total Lignin ◽  
Total Lignin Content

One of the characteristics of hyperhydric plants is the reduction of cell wall lignification (hypolignification), but how this is related to the observed abnormalities of hyperhydricity (HH), is still unclear. Lignin is hydrophobic, and we speculate that a reduction in lignin levels leads to more capillary action of the cell wall and consequently to more water in the apoplast. p-coumaric acid is the hydroxyl derivative of cinnamic acid and a precursor for lignin and flavonoids in higher plant. In the present study, we examined the role of lignin in the development of HH in Arabidopsis thaliana by checking the wild-types (Ler and Col-0) and mutants affected in phenylpropanoid biosynthesis, in the gene coding for cinnamate 4-hydroxylase, C4H (ref3-1 and ref3-3). Exogenously applied p-coumaric acid decreased the symptoms of HH in both wild-type and less-lignin mutants. Moreover, the results revealed that exogenously applied p-coumaric acid inhibited root growth and increased the total lignin content in both wild-type and less-lignin mutants. These effects appeared to diminish the symptoms of HH and suggest an important role for lignin in HH.

scholarly journals DEFORMAÇÃO RESIDUAL LONGITUDINAL E SUA RELAÇÃO COM ALGUMAS CARACTERÍSTICAS DE CRESCIMENTO E DA MADEIRA EM CLONES DE EUCALYPTUS

FLORESTA ◽  
2003 ◽  
Vol 33 (3) ◽  
Author(s):  
Marcos Aurélio Mathias De Souza ◽  
Paulo Fernando Trugilho ◽  
José Tarcísio Lima ◽  
Sebastião Carlos Da Silva Rosado
Keyword(s):  
Tree Growth ◽  
Lignin Content ◽  
Residual Deformation ◽  
Growth Characteristics ◽  
Dry Density ◽  
Grain Angle ◽  
Cleavage Strength ◽  
Tangential Shrinkage ◽  
Total Lignin ◽  
Total Lignin Content

Os objetivos deste trabalho foram verificar a variação da deformação residual longitudinal em clones de eucaliptos e determinar a sua correlação com algumas características físicas e mecânicas da madeira e com as de crescimento da árvore. Os resultados indicam que a deformação residual longitudinal (DRL) não apresentou correlação significativa com as características de crescimento da árvore e com os teores de lignina insolúvel, solúvel e total. A DRL apresentou correlação positiva e significativa com o índice de rachamento, as densidades básica e seca, desvio da grã, contração volumétrica, radial e tangencial e resistência ao fendilhamento. LONGITUDINAL RESIDUAL DEFORMATION AND YOUR RELATIONSHIP WITH SOME CHARACTERISTICS OF GROWTH AND OF THE WOOD IN CLONES OF EUCALYPTUS Abstract This research aimed to evaluate the variation of the longitudinal residual deformation of eucalyptus clones and to determine the correlation among the longitudinal residual deformation and tree growth characteristics and with some wood characteristics. The results indicate that the longitudinal residual deformation (DRL) didn’t present significant correlation with tree growth characteristics and insoluble, soluble and total lignin content. The DRL presented positive and significant correlation with the split index, the basic and dry density, grain angle, volumetric, radial and tangential shrinkage and cleavage strength.

The influence of lignin chemistry and ultrastructure on the pulping efficiency of clonal aspen (Populus tremuloides Michx.)

Holzforschung ◽  
2006 ◽  
Vol 60 (2) ◽  
pp. 111-122 ◽  
Author(s):  
Jaclyn J. Stewart ◽  
John F. Kadla ◽  
Shawn D. Mansfield
Keyword(s):  
Populus Tremuloides ◽  
Lignin Content ◽  
Insoluble Fraction ◽  
Pulp Yield ◽  
Wood Chemistry ◽  
Structural Differences ◽  
Chemical Pulping ◽  
Degree Of Condensation ◽  
Total Lignin ◽  
Total Lignin Content

Abstract The variation in wood chemistry among aspen clones of similar age, harvested from a common site in northern British Columbia, Canada, was evaluated. The aspen clones were evaluated for ease of chemical pulping and differed by as much as 4.5% in pulp yield at a common H-factor. The results demonstrate both the need for understanding the resource and the substantial opportunities that exists in natural population of trees for selecting superior clones for reforestation and afforestation. The syringyl/guaiacyl ratio, as determined by nitrobenzene oxidation, was directly correlated with the ease of pulping, whereas thioacidolysis results were not as predictive. These results were supported by quantitative NMR analysis, which demonstrated differences in the amount of β-O-4/Ar groups and the degree of condensation. Furthermore, it was shown that, in addition to total lignin content, which differed by as much as 5%, structural differences in the lignin may influence pulping efficacy. Among the other parameters evaluated, the distribution of molecular mass and methoxyl content is relevant for pulping. More specifically, among the fractions isolated in this study [milled wood lignin (MWL), MWELsol, and MWELinsol], the insoluble fraction was the most indicative of the pulping efficiency.

The Impact of Lignin Content on Paper Physical Strength of CTMP

2011 ◽  
Vol 236-238 ◽  
pp. 1242-1245
Author(s):  
Ben Ping Lin ◽  
Bei Hai He ◽  
Guang Lei Zhao
Keyword(s):  
Lignin Content ◽  
Strength Properties ◽  
Paper Strength ◽  
Fiber Morphology ◽  
Burst Strength ◽  
Physical Strength ◽  
The Impact ◽  
Linear Correlations ◽  
Total Lignin ◽  
Total Lignin Content

The research reported here gives some new insights into the influence of lignin content on paper strength properties. The relative amount of total lignin in CTMP was varied by using multistage ClO2 bleaching method. Few differences were observed in fiber morphology charcteristics of CTMP during ClO2 treatments. Linear correlations greater than 99% were found between total lignin content and paper strength properties. The influences of lignin content on Scott bond and tensile strength were greater than that of tear and burst strength.

Simplified determination of total lignin content in kraft lignin samples and black liquors

Holzforschung ◽  
2011 ◽  
Vol 65 (4) ◽  
Author(s):  
Fredrik Aldaeus ◽  
Hannah Schweinebarth ◽  
Per Törngren ◽  
Anna Jacobs
Keyword(s):  
Acid Hydrolysis ◽  
Standard Method ◽  
Lignin Content ◽  
Kraft Lignin ◽  
Black Liquors ◽  
Total Lignin ◽  
Total Lignin Content

Abstract Determination of total lignin content in lignin samples and black liquors using methods with reduced or omitted acid hydrolysis has been compared to the standard method, and results show that the simplified methods yield equivalent results.

scholarly journals Monitoring transformation of two tropical lignocellulosics and their lignins after residence in Benin soils

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rodrigue Daassi ◽  
Pierre Betu Kasangana ◽  
Damase P. Khasa ◽  
Tatjana Stevanovic
Keyword(s):  
Quantum Coherence ◽  
Mineral Content ◽  
Lignin Content ◽  
Gmelina Arborea ◽  
Total Carbohydrate ◽  
N Enrichment ◽  
Field Incubation ◽  
Aryl Ethers ◽  
Total Lignin ◽  
Total Lignin Content

AbstractThermally assisted Hydrolysis and Methylation (THM), and 2D-heteronuclear single quantum coherence nuclear magnetic resonance (2D HSQC NMR) spectroscopy were used to monitor the transformation of ramial chipped wood (RCW) from Gmelina arborea and Sarcocephalus latifolius, together with their organosolv lignins, following soil incubation in Benin (West Africa). Mesh litterbags containing RCW were buried in soils (10 cm depth) and were retrieved after 0, 6, 12 and 18 months of field incubation. Chemical analysis showed that total carbohydrate content decreased, while total lignin content increased as RCW decomposition progressed. Ash and mineral content of RCW increased significantly after 18 months of decomposition in soil. Significant N-enrichment of the RCW was determined following 18 months incubation in soils, reaching 2.6 and 1.9 times the initial N-content for G. arborea and S. latifolius. Results of THM showed that the S + G sum, corresponding to lignins, increased with RCW residence time in the soils, in contrast to the response of compounds derived from carbohydrates, the sum of which decreased. Remarkably, lignin interunit linkages, most notably β-O-4′ aryl ethers, β-β′ resinol, β-5′ phenylcoumaran and p-PCA p-coumarate, survived after 18 months in the soil, despite their gradual decrease over the duration of the experiment.

scholarly journals An extensive parameter study of hydrotropic extraction of steam-pretreated birch

2021 ◽  
Author(s):  
Johanna Olsson ◽  
Michael Persson ◽  
Mats Galbe ◽  
Ola Wallberg ◽  
Ann-Sofi Jönsson
Keyword(s):  
Residence Time ◽  
Steam Explosion ◽  
Room Temperature ◽  
Initial Step ◽  
Parameter Study ◽  
Hydrothermal Degradation ◽  
Steam Explosion Pretreatment ◽  
Lignin Extraction ◽  
Extraction Step ◽  
Lignin Recovery

AbstractEfficient fractionation of lignocellulosic biomass is an important step toward the replacement of fossil-based products. However, the utilisation of all of the components in biomass requires various fractionation techniques. One promising process configuration is to apply steam explosion for the recovery of hemicelluloses and a subsequent hydrotropic extraction step for the delignification of the remaining solids. In this work, the influence of residence time, temperature and biomass loading on lignin recovery from birch using sodium xylene sulphonate as a hydrotrope was investigated. Our results show that residence time, temperature and biomass loading correlate positively with lignin extraction, but the effects of these parameters were limited. Furthermore, when steam explosion was implemented as the initial step, hydrotropic extraction could be performed even at room temperature, yielding a lignin extraction of 50%. Also, hydrothermal degradation of the material was necessary for efficient delignification with sodium xylene sulphonate, regardless of whether it occurs during steam explosion pretreatment or is achieved at high temperatures during the hydrotropic extraction.

Probing the molecular weights of sweetgum and pine kraft lignin fractions

TAPPI Journal ◽  
2021 ◽  
Vol 20 (6) ◽  
pp. 381-391
Author(s):  
JULIANA M. JARDIM ◽  
PETER W. HART ◽  
LUCIAN LUCIA ◽  
HASAN JAMEEL
Keyword(s):  
Molecular Weight ◽  
Black Liquor ◽  
Average Molecular Weight ◽  
Gel Permeation Chromatography ◽  
Systematic Investigation ◽  
Kraft Pulping ◽  
Molecular Weights ◽  
Lignin Recovery ◽  
Lignin Reactivity ◽  
Kinetics Of

The present investigation undertook a systematic investigation of the molecular weight (MW) of kraft lignins throughout the pulping process to establish a correlation between MW and lignin recovery at different extents of the kraft pulping process. The evaluation of MW is crucial for lignin characterization and utilization, since it is known to influence the kinetics of lignin reactivity and its resultant physicochemical properties. Sweetgum and pine lignins precipitated from black liquor at different pHs (9.5 and 2.5) and different extents of kraft pulping (30–150 min) were the subject of this effort. Gel permeation chromatography (GPC) was used to deter- mine the number average molecular weight (Mn), mass average molecular weight (Mw), and polydispersity of the lignin samples. It was shown that the MW of lignins from both feedstocks follow gel degradation theory; that is, at the onset of the kraft pulping process low molecular weightlignins were obtained, and as pulping progressed, the molecular weight peaked and subsequently decreased. An important finding was that acetobromination was shown to be a more effective derivatization technique for carbohydrates containing lignins than acetylation, the technique typically used for derivatization of lignin.

scholarly journals The Potential of Candida Biofilm Protein as Bioreceptor for Candidiasis Immunoassay

2018 ◽  
Vol 14 (1) ◽  
pp. 47 ◽  
Author(s):  
Masfufatun Masfufatun ◽  
Loo Haryanto ◽  
Harsono Harsono
Keyword(s):  
Molecular Weight ◽  
Candida Albicans ◽  
Polyclonal Antibody ◽  
Control Group ◽  
Potential Candidate ◽  
Dot Blot ◽  
Protein Extract ◽  
Treatment Groups ◽  
Sds Page ◽  
Mechanical Methods

Abstract: Candidiasis or infection that is caused by Candida has become a new list of the therapeutical problems recently. The difficulties in diagnosing are the main cause of the unsatisfactory results from common therapies and diagnosis methods. This has urged researchers to find alternative ways in candidiasis diagnosis such as serology-based detection using antigen or antibody development. The aim of this study was to evaluate the potential of protein derived from Candida albicans biofilm as bioreceptor on candidiasis immunoassay through Dot Blot method. The research method used descriptive method with the following stages: (1) preparation of Candida albicans biofilm (2) extraction of Candida albicans protein through enzymatic and mechanical methods, (3) determination of protein molecular weight with SDS-PAGE (4) production of polyclonal anti- candida and (5) analysis of protein extract as bioreeceptor on dot blot. Profile of biofilm proteins on SDS-PAGE analysis were shown on molecular weight 27,42; 29,89; 38,10; 44,90; 48,75; 52,92; 55,14; 59,86; 70,56; 87,36; 102,54;115,05; 130,14;143,14;181,53 kD. There were differences in the intensity of dots in the control group (44070) and treatment groups (63170.5). It is noticeable that biofilm protein extract of C. albicans can be used for induction of anti-Candida polyclonal antibody production as the potential candidate of bioreceptor in candidiasis immunoassay. Keywords: SDS-PAGE, polyclonal antibody, immunoassay, dot blot, biofilm

scholarly journals Optimization of the Process of Abies Wood Peroxide Delignification in the Medium “Formic Acid-Water” in the Presence of TiO₂ Catalyst

2019 ◽  
pp. 522-535
Author(s):  
Natalya V. Garyntseva ◽  
Irina G. Sudakova ◽  
Anna I. Chudina ◽  
Yuri N. Malyar ◽  
Boris N. Kuznetsov
Keyword(s):  
Molecular Weight ◽  
Formic Acid ◽  
Lignin Content ◽  
Average Molecular Weight ◽  
Mathematical Optimization ◽  
Acid Water ◽  
Water Medium ◽  
Residual Lignin ◽  
Acetic Acid Water ◽  
Peroxide Delignification

The experimental and mathematical optimization of abies wood peroxide delignification process in the formic acid – water medium in the presence of TiO₂ catalyst was carried out. It was established that in the temperature range 70-100 °С the rate constants of the delignification process vary between 0.4 and 3.2 · 10-4 min-1. The optimal parameters for the production of cellulose product with a residual lignin content of ≤ 3 wt.% were determined (temperature 100 °С, concentration Н₂О₂ 10 wt.%, НCOOН 38 wt.%, LWR 15, time 4 h). The features of abies wood peroxide delignification processes in the presence of TiO₂ catalyst in “ formic acid – water” and “acetic acid – water” were compared. It was shown the possibility of abies wood fractionation in the medium “ formic acid-water” to high-quality cellulose with the yield of 94 wt.% (the content of residual lignin 2.3 wt.%) and to low molecular weight lignin with the yield of 21 wt.% (average molecular weight 1854 g/mol and polydispersity 1.65). The obtained chemically active lignin can be used for the production such valuable products as enterosorbents, nanoporous carbon materials, aerogels

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