Browsing by Author "Tuyet Dang, Ngan Thi"

A large amount of precious metals containing e-waste and wastewater is discharged into environment every day. Recovery of these metals can help not only protecting environment but also balancing their supply and demand. Supported liquid membrane with strip dispersion (SLMSD) is among the promising methods to recover metals from waste sources. Theoretically, simultaneous extraction and stripping using hydrophobic membrane would allow zero-waste as well as high metal concentration in receive phase. This research investigated the ability of recovering different metals such as indium, europium, yttrium using SLMSD. The investigation proved that SLMSD was able to remove more than 99.5 % metal ions from wastewater or leaching solution. High metal concentration was obtained by adjusting feed to strip volume ratio.

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.