화학공학소재연구정보센터
Industrial & Engineering Chemistry Research, Vol.43, No.19, 5989-5995, 2004
Electrolytic preparation of vanadium(II) formate in pilot-plant scale using stainless steel mesh electrodes: Dissolution of alpha-Fe2O3/Fe1.6Cr0.4O3 in an aqueous V-II-NTA complex
The chemical formulations containing strong reducing agents such as V(II) are kinetically effective for the reductive dissolution of iron oxides such as Fe3O4, Fe2O3, etc. To develop a methodology for large-scale synthesis of V(II), we report here the details of an electrolytic preparation on a pilot-plant scale (50 L). It is demonstrated that, by using stainless steel mesh cathode and anode in a poly(tetrafluoroethylene)-lined stainless steel tank, V(II) could be prepared. To minimize the electrolysis duration for the conversion of V(V) to V(II), laboratory studies are carried out for a preliminary reduction of V(V) to V(IV) with hydrazine or ascorbic acid and then employing V(IV) for electrolysis. Here, the use of hydrazine was advantageous (30% less time) over that of ascorbic acid. The V(II) obtained was complexed with nitrilotriacetic acid (NTA), and its stability and dissolution kinetics of Fe2O3 and Fe1.6Cr04O3 in the V-II-NTA formulation are reported.