Surfactant stabilisation of colloidal lignin microparticulates produced through a solvent attrition process

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Physicochemical and engineering aspects, 2016-06, Vol.498, p.194-205
• Main Authors: Stewart, Hayley, Golding, Matt, Matia-Merino, Lara, Archer, Richard, Davies, Clive
• Format: Article
• Language: English
• Subjects: Agglomeration; Charged particles; Electrostatic; Microparticles; Particle size; Precipitation; Precipitation (chemistry); Reduction; Repulsion; Solvents; Surface chemistry; Surfactants; Wetting
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2016.03.001

[Display omitted] •Lignin microparticles can be produced via a solvent precipitation process.•Particle size and structure are influenced by surfactant type.•Stabilisation of lignin microparticles occurs through electrostatic repulsion. The stabilisation of insoluble lignin microparticulates produced through solvent attrition in aqueous media containing surfactants has been investigated. In the absence of added surfactants, addition of solvent solubilised lignin to water caused extensive precipitation and annealing of lignin, leading to the formation of large, agglomerated structures in the approximate size range of 20–200μm. Addition of high HLB non-ionic surfactants (Polysorbate 20/sucrose ester) to the aqueous solution prior to lignin precipitation had only limited effect on the size of agglomerates produced, with a partial decrease in mean aggregate size at elevated surfactant concentrations, and no observed effect at low surfactant concentrations. In contrast, addition of either negatively (SDS) or positively (CTAB) charged ionic surfactants at concentrations