Solvent screening for the fractionation of industrial kraft lignin

Duval, Antoine; Vilaplana, Francisco; Crestini, Claudia; Lawoko, Martin

doi:10.1515/hf-2014-0346

Cited by 194 publications

(246 citation statements)

References 51 publications

Supporting

Mentioning

225

Contrasting

Unclassified

Order By: Relevance

“…On the other hand, polarity and hydrogen bonding ability seemed to play a crucial role in lignin dissolution. To some extent, this is an expected outcome, which confirms what has been reported in the literature (Duval et al 2015) …”

Section: Determination Of Hansen Parameterssupporting

confidence: 91%

Lignin Prepared by Ultrafiltration of Black Liquor: Investigation of Solubility, Viscosity, and Ash Content

Giummarella¹,

Lindgren²,

Lindström³

et al. 2016

BioResources

View full text Add to dashboard Cite

Technical lignin, which can be potentially obtained in large amounts as a by-product from kraft pulping, represents a potential resource for manufacturing fuels and chemicals. Upgrading of lignin, by lowering its molecular weight, is a valuable alternative to precipitation from black liquor, which occurs in the Lignoboost process. The solubility properties of Lignoboost lignin and filtered lignin in a number of technically feasible solvents were compared, and it was found that both lignins were dissolved in similar solvents. With the exception of furfural, the best lignin solvents generally were organic solvents miscible with water, such as methanol. It was possible to dissolve more filtered lignin in higher concentrations than Lignoboost lignin; additionally, the viscosities of the filtered lignin solutions were also considerably lower than those of Lignoboost lignin, especially at higher concentrations. Methods for non-organic component removal from filtrated lignin were tested, and it was concluded that several cold acidic treatments after dewatering can lower the ash content to values below 0.5% by weight.

show abstract

Section: Determination Of Hansen Parameterssupporting

confidence: 91%

Lignin Prepared by Ultrafiltration of Black Liquor: Investigation of Solubility, Viscosity, and Ash Content

Giummarella¹,

Lindgren²,

Lindström³

et al. 2016

BioResources

View full text Add to dashboard Cite

show abstract

“…10,11 Furthermore, recent advances in the isolation of low polydispersity lignin fractions, either by membrane filtration [12][13][14] or solvent fractionation, 15,16 are contributing to enhance its potential use. Despite huge efforts devoted towards its structural characterization during the last decades, a clear idea of its molecular structure emerged only in the last years with the development of advanced heteronuclear 2D NMR techniques.…”

Section: Introductionmentioning

confidence: 99%

Reversible crosslinking of lignin via the furan–maleimide Diels–Alder reaction

et al. 2015

Self Cite

View full text Add to dashboard Cite

Two distinct functionalization schemes for Kraft lignin (KL) were developed to selectively incorporate furan and/or maleimide motifs as chain ends. The incorporation of furan functionalities was carried out by the selective and quantitative reaction of the lignin's phenolic OH groups with furfuryl glycidyl ether (FGE). Maleimide groups were introduced by esterifying the lignin's aliphatic and phenolic OH groups with 6 maleimidohexanoic acid (6-MHA), offering a high loading despite a somewhat incomplete conversion. Furan-and maleimide-functional lignins were subsequently combined to generate crosslinking via the Diels-Alder (DA) [4 + 2] cycloaddition reaction. The formation of the DA adduct was confirmed by 1 H NMR. Under appropriate conditions, the formation of a gel was apparent, which turned back into the liquid state after performing the corresponding retro-DA reaction upon heating to 120 °C. This study displays the significant versatility and potential of the developed strategy for the utilization of lignin-based recyclable networks.The Diels-Alder (DA) [4+2] cycloaddition between furan and maleimide moieties, which respectively act as diene and dienophile, represents, among others, an interesting tool to generate bonds in a reversible fashion. 28 It presents several advantages, such as the low temperatures required to perform the forward and retro reactions, at 60-70 and 110-120°C, respectively, which are compatible Figure 4. FTIR spectra of the functionalized lignins, depending on the amount of FGE used for functionalization (a) and evolution of the furan peaks heights with the amount of FGE used for functionalization (b). Lignin functionalization with maleimide moietiesThe second step of the work consisted in the grafting of maleimide groups onto lignin. This was accomplished by esterification with 6-maleimidohexanoic acid (6-MHA), as shown in Scheme 2.In order to increase the reaction yield, 6-MHA was first converted into the corresponding acyl chloride by reacting with oxalyl chloride (Scheme 2a). The solution of acyl chloride was then directly transferred into the lignin solution to perform the esterification (Scheme 2b). The reaction has been 14 performed with increasing amounts of 6-MHA and followed by 31 P NMR, 1 H NMR and UV spectroscopy. All data are given in Table 2.Scheme 2. 2-steps maleimidation of lignin: conversion of 6-maleimidohexanoic acid (6-MHA) into the corresponding acyl chloride (a) and esterification of lignin with 6-maleimidohexanoic acyl chloride (b).A preliminary study on the kinetic of the reaction showed that 1 h was sufficient to achieve the maximum functionalization yield (supplementary information, Figure S4). The content in OH groups was measured by 31 P NMR, whereas UV spectroscopy was used to monitor the content in phenolic OH groups. Some samples couldn't be analyzed by 31 P NMR, because they were insoluble in the solvent mixture after phosphitylation. In this case only the UV data are reported in Figure 5a.Nevertheless, when both 31 P NMR and UV data are available, a good...

show abstract

“…The reported results are very preliminary in terms of lignin utilization, as it is obvious that for value-added lignin applications fractionation and upgrading is necessary (Brodin et al 2009(Brodin et al , 2012Gosselink et al 2010;Ropponen et al 2011;Duval et al 2015Duval et al , 2016Fang et al 2015). Selective precipitation and ultrafiltration are potentially useful techniques, depending on the intended lignin application (Brodin et al 2009;Toledano et al 2010;Ponomarenko et al 2014;Sevastyanova et al 2014;Duval et al 2015).…”

Section: Resultsmentioning

confidence: 98%

“…Studies with kraft lignin in focus are mainly in close relation to the delignification mechanism (Marton 1964;Marton and Marton 1964;Gellerstedt and Lindfors 1984;Sjöholm et al 1993;Jacobs and Dahlman 2001;Dodd et al 2015), but there are also data available concerning the recovery and fractionation of lignins (Toledano et al 2010;Saito et al 2014;Sevastyanova et al 2014;Alekhina et al 2015;Duval et al 2016). A commercially available kraft lignin recovery process that is suitable for industrial applications is the LignoBoost process, in the course of which a part of the kraft lignin dissolved in the black liquor (BL) is precipitated by acidification, washed, and dried resulting in a solid lignin powder (Tomani 2010).…”

Section: Introductionmentioning

confidence: 99%

COST Action FP1105: effect of raw materials and pulping conditions on the characteristics of dissolved kraft lignins

et al. 2016

View full text Add to dashboard Cite

Abstract:The composition, molecular weight (MW), and chemical structure of technical lignins as byproducts of pulping influence their application in terms of physical and chemical properties, reactivity, and performance. It is important to know how the analytical data of technical lignins are influenced by the wood species and the parameters of pulping. The present study focuses on kraft pulping and how the wood species (eucalyptus, pine, and spruce) and variable cooking times influence the characteristics of dissolved lignins. The black liquor (BL) was recovered after three different cooking times and the precipitated lignin was characterized by total acid hydrolysis including the determination of the acid insoluble part (Klason lignin, KL) and the sugars in the hydrolysate, elemental analysis, 31 P NMR spectroscopy, analytical pyrolysis (Py-GC/MS), gel permeation chromatography (GPC), thermogravimetry (TG), and differential scanning calorimetry (DSC). The results indicate that the phenolic OH content, MW and glass transition temperature increased with longer cooking times for the softwood (SW) lignins. These lignins had also a higher MW (M w 5500-8000 g mol -1 ), than the eucalyptus lignin (M w 2200-2400 g mol -1 ). Eucalyptus lignin had higher sulfur content compared to SW.

show abstract

Solvent screening for the fractionation of industrial kraft lignin

Cited by 194 publications

References 51 publications

Lignin Prepared by Ultrafiltration of Black Liquor: Investigation of Solubility, Viscosity, and Ash Content

Lignin Prepared by Ultrafiltration of Black Liquor: Investigation of Solubility, Viscosity, and Ash Content

Reversible crosslinking of lignin via the furan–maleimide Diels–Alder reaction

COST Action FP1105: effect of raw materials and pulping conditions on the characteristics of dissolved kraft lignins

Contact Info

Product

Resources

About