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 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.

Determination of lignin content in kraft black liquors by capillary zone electrophoresis (CZE)

Holzforschung ◽  
2013 ◽  
Vol 67 (8) ◽  
pp. 887-890 ◽  
Author(s):  
Getachew Gizaw Gebremeskel ◽  
Fredrik Aldaeus
Keyword(s):  
Capillary Zone Electrophoresis ◽  
Multivariate Calibration ◽  
Degradation Products ◽  
Lignin Content ◽  
Standard Normal Variate ◽  
Zone Electrophoresis ◽  
Standard Normal ◽  
Capillary Zone ◽  
Black Liquors

Abstract Capillary zone electrophoresis (CZE) in an alkaline glycine buffer is suggested for the quantification of lignin content in black liquors (BL). The method was first tested by an external calibration with LignoBoost lignins. Then, the lignin content in BL was determined by means of a multivariate calibration with the application of a standard normal variate filter and partial least squares approach based on five principal components. The results are in agreement with those obtained by sulfuric acid lignin precipitation combined with ultraviolet measurement of the lignin in solution. The advantage of the CZE method is its independence from the knowledge of the exact absorptivity coefficient, which is needed for direct spectrophotometric lignin determination. Moreover, interfering substances and degradation products could be recognized and excluded from lignin determination; thus, the selectivity was increased significantly.

The Composition of Crude Fibre

1935 ◽  
Vol 25 (4) ◽  
pp. 529-540 ◽  
Author(s):  
A. G. Norman
Keyword(s):  
Acid Hydrolysis ◽  
Direct Effect ◽  
Lignin Content ◽  
Alkaline Treatment ◽  
Empirical Method ◽  
Crude Fibre ◽  
Definite Relationship ◽  
Alternative Method ◽  
Made In

The crude-fibre determination is misleading, because the fraction obtained does not bear any definite relationship to the structural constituents of the material. The cellulose is partially attacked, and lignin extensively removed. Considerable variation is found in the lignin content of crude-fibre fractions. Highly lignified materials do not necessarily yield a crude fibre high in lignin.Since the presence of lignin exercises a direct effect on the digestibility of the material, any empirical method should include all the lignin, and alkaline treatment must be avoided. Acid hydrolysis may be a possible alternative method, if a correction for protein be made in the case of materials high in nitrogen, and a determination of the lignin content made.

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.

DETERMINATION OF LIGNIN IN CEREAL STRAWS

1949 ◽  
Vol 27b (12) ◽  
pp. 915-923 ◽  
Author(s):  
G. A. Adams ◽  
A. E. Castagne
Keyword(s):  
Hydrochloric Acid ◽  
Sulphuric Acid ◽  
Lignin Content ◽  
Maximum Amount ◽  
Dilute Acid ◽  
Rye Straw ◽  
Total Lignin ◽  
Minimum Yield

Determination of lignin in wheat, oat, barley, and rye straw with 64%, 68%, 72%, 76%, and 80% (wt.) sulphuric acid showed that a minimum yield of lignin containing a maximum amount of methoxyl was obtained with the 72% sulphuric acid. In this respect, cereal straws differ from deciduous woods for which 72% sulphuric acid lignin determinations are unsuitable. Comparison of lignin determinations made with 72% sulphuric acid and with 42% fuming hydrochloric acid, on the same straws, after pretreatment with 1.0% hydrochloric acid, showed that the former method preserves a larger proportion of the methoxyl groups. Both methods recovered more total lignin methoxyl from untreated than from treated straws, with the sulphuric acid retaining the larger amount. It is concluded that lignin determination with 72% sulphuric acid on straws untreated with dilute acid yields a residue most representative of the 'true' lignin content, based on the criterion of maximum methoxyl recovery.

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