Quinoline and cholesterol based organogelator for selective adsorption of cationic dyes

Abstract

A novel quinoline and cholesterol based organogelator G1 has been successfully synthesized and characterized. G1 could form stable organogels in ethanol, n-propanol, n-butanol, isobutanol, acetone and ethyl acetate (EA), and the concentration-dependent 1HNMR revealed that hydrogen bonding, π-π stacking and van der Walls interaction were the main driving force to form organogels via the self-assembly of G1. Furthermore, the G1-EA gel realized selective adsorption properties for cationic dyes, such as malachite green (MG), brilliant green (BG), rhodamine B (RB) and crystal violet (CV). The results revealed that at pH = 9.90, c0 = 18 mg·L−1, the adsorption process of G1-EA gel for MG reached equilibrium in 7 h, and the removal rate was 99.13 %. The selective adsorption experiments of the G1-EA gel indicated that the cationic dyes (MG and BG) were efficiently adsorbed out of the mixed dyes solutions. Also, the adsorption isotherm and the adsorption kinetics for the adsorption process were investigated, the results suggested that the Freundlich equation and the quasi-second-order kinetic model were more appropriate to describe the adsorption process.