Separation of niobium(V) and tantalum(V) by applying liquid-film technique

For separating niobium(V) and tantalum(V) by applying liquid-film technique, the authors probe into experimental condition under which Nb(V) will be extracted and adopt nitric acid-hydrogen fluoride system to dissolve niobium axide and tantallic oxide. As shown by the experiment, the extraction of Nb(V) is controlled by the concentration of hydrogen ions and hydrogen fluoride in case para-octyl alcohol is taken as carrier; and Nb(V) can be effectively extracted in the medium of 6 mol · L-1 sulfuric acid-2 mol · L-1 hydrogen fluoride in case tri-n-octyl amine (TNOA) is taken as carrier. Based on the condition of Nb(V) and Ta(V) extraction by applying liquid-film technique, they are separated. The results indicate that Nb(V) and Ta(V) can be effectively separated in the medium of 6 mol · L-1 sulfuric acid-0.5 mol · L-1 hydrogen fluoride in case para-octyl alcohol is taken as carrier.