Removal of Iron(III) and Aluminum Ions from Phosphoric Acid–Nitric Acid Solutions by S957 Chelation Resin: Kinetics, Dynamic Adsorption, and Elution

Removal of iron(III) and aluminum ions from phosphoric acid–nitric acid (PA-NA) solutions including their batch adsorption kinetics on the sulfonic/monophosphonic acid chelation resin (S957) and the dynamic adsorption–elution process at the different operating parameters is studied. The results reveal that Fe(III) and Al(III) ions in PA-NA solutions on S957 resin present the slow batch adsorption rate. Their adsorption equilibriums are reached at 60 and 40 min contact times, respectively. The dynamic adsorption process of Fe(III) and Al(III) ions is dependent on the feed flow rate through the fixed-bed column, and at the 0.5 mL·min –1 flow rate, Fe(III) and Al(III) ions can be greatly removed from PA-NA solutions. In the dynamic elution process, the flow rate shows a little effect on the elution process of Fe(III) and Al(III) ions. The better regeneration solution for the dynamic elution process is HCl solution, and the optimized concentration of HCl solution is 8 mol·L –1 .