Abstract:
In this study, extraction and recovery of platinum ions from gold-refining co-produced water via hollow fiber supported liquid membrane (HFSLM) containing Methyl-trioctyl-ammonium chloride (Aliquat 336) dissolved in kerosene as carrier were examined. The important factors were studied such as types of carriers, pH value of feed solution, the concentration of carrier, the types and concentration of stripping solutions, the flow rates of feed and stripping solutions, the operating temperature, and types of diluents. Among the stripping reagents tested, 0.2 M NaClO4 was effectively found to strip platinum ions more than other reagents. At the pH value of feed solution of 2, the percentage of platinum extraction increases when concentration of Aliquat 336 increases up to 15% (v/v), subsequently decreases. In addition, it was found that the platinum transport is enhanced when temperature increases. The mass transfer coefficients of the aqueous phase (ki) and membrane phase (km) were 5.872 and 6.396×10-3 cm/s, respectively. Therefore, the mass transfer limiting step is the diffusion of platinum complex through liquid membrane.