Construction of sulfonate-functionalized micro/nano hybrid absorbent for Li+-ions separation using Pickering high internal phase emulsions template

Abstruct In this work, Halloysite nanotubes (Hal) were modified by polystyrene sulfonate (PSS) firstly and then employed as stabilizer particles for Pickering high internal phase emulsions (Pickering HIPEs). Later, a kind of sulfonate-functionalized micro/nano hybrid absorbent was fabricated through Pickering HIPEs template method based on the so-prepared PSS-modified Hal. Owing to an enhanced synergy between the sulfonate-functionalized polymer and the PSS-modified Hal stabilizer, which both had lots of sulfonate groups (R-SO3−, binding sites), this so-fabricated sulfonate-functionalized micro/nano hybrid absorbent possessed a dual adsorption role for Li+ ions and a fast adsorption kinetics performance. According to adsorption experiments, its adsorption equilibrium state was finished at about 360 min, while 600 min for the contrast sample. Furthermore, its maximum actual adsorption capacity (Qe) was about 23.9 mg/g, higher than 14.5 mg/g of contrast sample. Consequently, the sulfonate-functionalized micro/nano hybrid absorbent with a high adsorption capacity and a fast adsorption kinetics performance was a promising material for Li+ extraction from brine.