Sulfomethylation of lignins

Madzhidova, V. E.; Dalimova, G. N.; Abduazimov, Kh. A.

doi:10.1007/bf02249140

Cited by 9 publications

(15 citation statements)

References 1 publication

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“…The anionic charge density increased from 0t oÀ1.6 meq g À1 ,t he molecular weighti ncreased from about 22 700 to 53 400 gmol À1 ,a nd the sulfonate group content increased from 0.03 to 1.48 mmolg À1 . [94] In ap rocess similart ot hat outlinedi nS cheme 9, dioxane lignin, nitrolignin, and hydrolysis lignin, amongo thers, were reported to be used under the conditions of 0.5:1 (w/v) lignin/CH 2 Oa nd 1:1( w/w)l ignin/Na 2 SO 3 at pH 8a nd 95 8Cf or 3h. [28] The benefito fr eactingw ith sodium hydroxymethyl sulfonate is to avoid two reactions tages, and to develop as imple process for producings ulfonated lignin, but, in this case, the molecularw eight of the product is low relative to that of the two-step process.…”

Section: Sulfomethylationmentioning

confidence: 96%

“…[93] Other technical lignins were also subjected to sulfomethylation. [94] In ap rocess similart ot hat outlinedi nS cheme 9, dioxane lignin, nitrolignin, and hydrolysis lignin, amongo thers, were reported to be used under the conditions of 0.5:1 (w/v) lignin/CH 2 Oa nd 1:1( w/w)l ignin/Na 2 SO 3 at pH 8a nd 95 8Cf or 3h. [94] The product could be subjected to purificationa sr equired.…”

Section: Sulfomethylationmentioning

confidence: 96%

“…[28] Alternatively,s ulfomethylated kraft lignin was proposed to be produced at am olar ratio of 1:0.9 lignin/ sodium hydroxymethyl sulfonate at 100 8Cf or 3h without cross-linking. [94] The product could be subjected to purificationa sr equired. However,s ulfomethylation may form condensed lignin structures,w hich hinder the reactivity of the product by having reactive sites blockedb ythe resultingc omplex structures.…”

Section: Sulfomethylationmentioning

confidence: 99%

“…[28] The benefito fr eactingw ith sodium hydroxymethyl sulfonate is to avoid two reactions tages, and to develop as imple process for producings ulfonated lignin, but, in this case, the molecularw eight of the product is low relative to that of the two-step process. [94] However,t he more condensed lignin (demethylatedl ignin, chlorolignin) was reported to behave poorly in the sulfomethylation reaction. [93] Other technical lignins were also subjected to sulfomethylation.…”

Section: Sulfomethylationmentioning

confidence: 99%

“…However,s ulfomethylation may form condensed lignin structures,w hich hinder the reactivity of the product by having reactive sites blockedb ythe resultingc omplex structures. [94] 3.9. [94] In ap rocess similart ot hat outlinedi nS cheme 9, dioxane lignin, nitrolignin, and hydrolysis lignin, amongo thers, were reported to be used under the conditions of 0.5:1 (w/v) lignin/CH 2 Oa nd 1:1( w/w)l ignin/Na 2 SO 3 at pH 8a nd 95 8Cf or 3h.…”

Section: Sulfomethylationmentioning

confidence: 99%

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Production and Application of Lignosulfonates and Sulfonated Lignin

2017

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Lignin is the largest reservoir of aromatic compounds on earth and has great potential to be used in many industrial applications. Alternative methods to produce lignosulfonates from spent sulfite pulping liquors and kraft lignin from black liquor of kraft pulping process are critically reviewed herein. Furthermore, options to increase the sulfonate contents of lignin-based products are outlined and the industrial attractiveness of them is evaluated. This evaluation includes sulfonation and sulfomethylation of lignin. To increase the sulfomethylation efficiency of lignin, various scenarios, including hydrolysis, oxidation, and hydroxymethylation, were compared. The application of sulfonated lignin-based products is assessed and the impact of the properties of these products on the characteristics of their end-use application is critically evaluated. Sulfonated lignin-based products have been used as dispersants in cement admixtures and dye solutions more than other applications, and their molecular weight and degree of sulfonation were crucial in determining their efficiency. The use of lignin-based sulfonated products in composites may result in an increase in the hydrophilicity of some composites, but the sulfonated products may need to be desulfonated with an alkali and/or oxygen prior to their use in composites. To be used as a flocculant, sulfonated lignin-based products may need to be cross-linked to increase their molecular weight. The challenges associated with the use of lignin-based products in these applications are comprehensively discussed herein.

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Section: Sulfomethylationmentioning

confidence: 96%

Section: Sulfomethylationmentioning

confidence: 96%

Section: Sulfomethylationmentioning

confidence: 99%

Section: Sulfomethylationmentioning

confidence: 99%

Section: Sulfomethylationmentioning

confidence: 99%

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Production and Application of Lignosulfonates and Sulfonated Lignin

2017

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Valorization of bagasse alkali lignin to water-soluble derivatives through chemical modification

Abdulkhani

Khorasani

Hamzeh

et al. 2022

Biomass Conv. Bioref.

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Black liquor is the by-product of the pulping process where the lignin, hemicellulose, and extractive materials are separated from wood to produce paper pulp. As one of the primary lignin sources, black liquor is considered an important energy source from biomass to produce biofuels and value-added chemicals. However, soda alkaline lignin has limited industrial applications due to its insolubility in water and lack of reactivity. Therefore, chemical modification is essential to enhance its industrial applications. In this study, alkali lignin from bagasse was modified through sulfonation, sulfomethylation, and amination processes using different reaction conditions. The structural analysis of obtained products was investigated by FTIR and 1 H-NMR. The molecular weight distribution and thermal stability of the watersoluble products were analyzed using gel permeation chromatography (GPC) and thermogravimetric analysis (TGA), respectively. The elemental analysis was used to measure the elements (CHNSO) of the obtained water-soluble derivatives. The chemical structure analysis of the samples with FTIR and 1 HNMR confirmed the modification processes. The results indicate that modification led to increased water solubility and a decrease in the precipitation pH of lignin samples, due to the introduction of sulfonate and amin functunal groups on lignin. In addition, the molecular weight and thermal stability of modified lignins were increased due to the presence of sulfonate and amine groups compared to unmodified lignin.

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