Abstract
In this study, a selective separation of tungsten W (VI) from a mixed salt solution was done through a liquid-membrane technology. The transport of W (VI) across the supported liquid membrane was also applied on real sample. Tertiary amine (Tri-n-dodecylamine) was used as an organic carrier and a supported liquid membrane of polypropylene separator (celgard 2400) was used in this experimental work. The selective separation of W (VI) was optimized by various parameters i.e., concentration of metal in feed, concentartion of stripping agent, type of stripping reagents, carrier concentration and pH effect. The extraction of W(VI) was maximized by the concentration of carrier up to 0.2 mol/dm(3)diluted inn-hexane. The optimum concentration of sodium hydroxide was 0.2 mol/dm(3)in the strip phase. The transport of tungsten increases by the increase of the pH of feed solution to basic from acidic up to the pH 8. At pH 8 in the feed phase, tri-n-dodecylamine efficiently extracted W (VI) from feed through anion exchange mechanism. The time duration for the transport of tungsten was 6 h at room temperature. The optimized reaction of W(VI) for the selective separation was applied on the scheelite ore with 93% recoved. The single membrane was used in all experiments, which confirmed the durability and stability of polypropylene membrane.