Methodological approach for the estimation of the experimental surfactant:clay ratio in the production of large-scale organo-mineral complexes

Abstract

Organoclays are used in the production of nanomaterials in electronic devices, pharmaceutical and cosmetic industry, textile processes, energy, agricultural field, etc. Their relevance is motivated because of its capability to undergo tailor-surface modification by introducing organic functional moieties. Montmorillonite has been extensively the most widely used clay mineral due to its high surface area, high cation exchange capacity and expansive properties. The hydrophilic surface of this mineral can be fully or partially changed to hydrophobic by adsorption of cationic surfactants, usually of the quaternary alkylammonium cation type (QACs). On an industrial scale, it is necessary to use in its production a methodology that allows to establish a priori the surfactant:clay mineral ratios to be used to obtain the expected surfactant loading, in the sorption processes used. This work shows a methodology based on the Scatchard-Langmuir equation.