Effect of conventional and Gemini surfactants on the micellar-enhanced ultrafiltration process performance for the separation of Au(III) from aqueous solutions: A dissipative particle dynamics study

Abstract

Dissipative particle dynamics (DPD) simulation was used to investigate the self-assembled structure of dodecyl trimethyl ammonium bromide (DTAB) and Gemini hexamethylene-1, 6-bis (dodecyl dimethyl ammonium bromide) (12−6−12) surfactants in the aqueous solution. The influence of simulation time and surfactant concentration was studied as the effective parameters on the formation of micelles. The results indicate that by increasing the surfactant concentration, the micellar clusters deform to spherical, wormlike, cylindrical and lamellar shapes, respectively. Subsequently, the effect of surfactant and gold concentrations was investigated for the first time on the performance of the micellar-enhanced ultrafiltration (MEUF) process in the separation of Au(III) from aqueous solutions. The separation efficiency of gold mesomolecules and micellar binding constant was also estimated. The simulation results show the excellent effect of the presence of micelles in the separation of Au(III) using the MEUF process. As the surfactant concentration increases and the micelles grow in size, the probability of bonding between the metal mesomolecules and the micelles also increases and the passage of the gold beads through the polymeric membrane decreases.