Sorption of Mo (VI) From Nitric Acid Solution Using SM-4 Copolymer Resin Impregnated with CYANEX 923

Abstract

Sorption of molybdenum (VI) from nitric acid solution by solvent impregnated resin (SIR) technique using bio-beads styrene divinyl benzene copolymer (SM-4) impregnated with tri-alkyl phosphine oxide (CYANEX 923 or CY 923) extractant through batch and column techniques was investigated. The effects of the different parameters affecting the adsorption of Mo (VI) such as shaking time, V/m ratio, nitric acid, extractant, nitrate ion, hydrogen ion and metal ion concentrations as well as temperature were separately investigated. The batch results show that the extracted organic species is HMOO3(NO3).2CY and the average Kex value for Mo(VI) extraction using 30% CYANEX 923/SM-4 system was found to be 4.95 ± 0.2 M−3. The experimental results show that sorption of Mo (VI) obeys Freundlich isotherm. Desorption studies were carried out using different concentrations of stripping agents and maximum desorption was found to be 78% and 83% with 2 M sodium acetate and 0.25 MNaOH, respectively. Breakthrough curves indicate that column performs better with low feed, low flow rate and concentration and high bed height. An application was carried out on Gattar granite to recover Mo (VI) from other metals by applying the optimum experimental conditions of 30% CYANEX 923/SM-4 system and the obtained results indicate the selectivity of the investigated technique for molybdenum recovery from nitric acid solution.