Mass Transfer Performance Comparison between Conventional Solvent Extraction and Supported Liquid Membrane with Strip Dispersion for Indium Recovery from Waste Stream

Abstract

Solvent extraction is one of the most popular methods to recovery indium from wastewater. Multistage operation of conventional solvent extraction requires many extraction and stripping stages which leads to large foot print requirement and large amount of chemical usage. Supported liquid membrane with strip dispersion (SLMSD) allows simultaneous extraction and stripping which would lead to much more compact system as well as less solvent consumption. In this paper, the mass transfer rate of conventional solvent extraction (SX) and hollow fiber membrane contactor (SLMSD) were compared in different cases. Moreover, k.A values of SX and SLMSD in each case were also calculated (k is mass transfer coefficient and A is water – oil contact interfacial area). The results showed that mass transfer rate in SLMSD is slower than in solvent extraction due to smaller surface area of membrane contactor compared to interfacial area supplied by dispersion but the mass transfer coefficient is higher in SLMSD. The effect of oxalic acid – the co-occur inhibitor – is also investigated.