Study on supported combined liquid membrane containing HEH(EH)P and HNO3 for trivalent gadolinium transfer

A novel kind of supported combined liquid membrane (SCLM) has been studied for the Gd(III) transfer. SCLM contained polyvinylidene fluoride membrane (PVDF) as the liquid membrane support and renewal solution including HNO3 solution as the stripping solution and 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester (HEH(EH)P) as the carrier dissolved in kerosene. The mixed solution of carrier and kerosene was membrane solution. The optimum transport conditions of Gd(III) were that concentration of HNO3 solution was 4.00 mol/L, concentration of carrier was 0.16 mol/L, and volume ratio of membrane solution to stripping solution was 30:30 of the renewal phase, and pH value was 4.80 of the feed phase. Under the optimum condition studied, when initial concentration of Gd(III) was 1.00 × 10−4 mol/L, the transfer rate of Gd(III) was 96.8% during 130 min.