Using Sulfobutylated and Sulfomethylated Lignin as Dispersant for Kaolin Suspension

Abstract

Kraft lignin is an abundant natural resource, but it is underutilized. In this study, sulfoalkylated lignin derivatives with similar charge densities but with different alkyl chain length were produced via sulfobutylation and sulfomethylation reactions. The contact angle studies revealed that sulfobutylated lignin (SBL) with longer alkyl chains had a higher hydrophobicity than sulfomethylated lignin (SML) did. The adsorption behavior of sulfoalkylated lignins was studied using a Quartz crystal microbalance with dissipation (QCM-D) on Al2O3 coated surface as representative of positively charged sites of kaolin particles. The results of adsorption studies showed that SBL deposited more greatly than SML did on the Al2O3 surface, and it generated a thicker but less viscoelastic adlayer on the surface. The adlayer thickness and configuration of molecules on the surface were also related to the zeta potential and stabilization performance of the polymers in the kaolin suspension system. The results also confirmed that both lignin derivatives were very effective in dispersing kaolin particles at neutral pH, and their effectiveness was hampered under alkaline or acidic pH.

Lignin functionalization strategies and the potential applications of its derivatives – A Review

“…Hence, recent studies are focused on developing alternative sulfoalkylation reaction routes to alleviate its environmental impact. For instance, lignin sulfobutylation provides water-soluble lignin derivatives similar to conventional sulfomethylation with the advantage of being carried out in aqueous media (Eraghi Kazzaz et al 2019;Hopa and Fatehi 2020;Huang et al 2018). Sulfobutylation is a one-step reaction in which 1,4-butane sultone reacts with both phenolic and aliphatic hydroxyl groups of lignin (Fig.…”

“…Although sulfobutylation requires temperature and pressure lower than sulfomethylation, the sulfobutylation reagent is more expensive. Also, sulfobutylation leads to a higher degree of substitution because sulfomethylation is limited to lignin phenolic hydroxyl groups (Eraghi Kazzaz et al 2019;Hopa and Fatehi 2020).…”

“…Fig.9. Sulfobutylation of phenolic and aliphatic hydroxyl groups in lignin with 1,4-butane sultone (adapted fromHopa and Fatehi 2020) …”

Cationic Lignin Polymers as Flocculant for Municipal Wastewater

“…The solubility of the samples was determined following a previously established method [29,30]. The charge density of the samples was determined using a Particle Charge Detector (Mutek PCD 04, BTG Instruments GmbH, Herrsching, Germany) as described in the past [29,30].…”

Lignin-based composites for high-performance supercapacitor electrode materials

“…This confers good electrical conductivity to the conducting polymers. [19][20][21] In addition, the catechol/quinone groups on ligninsulfonate can be converted to each other by redox, and the introduction of polyaniline conducting polymers can promote the electron transfer in the redox process, which can further form a self-redox system. 22 In this thesis, ligninsulfonate/polyaniline nanocomposites were prepared from ligninsulfonate by in situ polymerization embedded in the conducting polymer polyaniline, and their structure, morphology and capacitive properties were characterized.…”