Sulfur dioxide-a leachant for oxidic materials in aqueous and non-aqueous media

摘要

Leaching of various oxide materials using sulfurdioxide is documented in this review. Emphasis is given to theleaching of Fe(III), Mn(IV), Mn(III) oxides/hydroxides highlightingthe mechanisms and kinetics of these systems. Treatment ofmagnesium oxide associated with serpentinic silicate tailings,copper - zinc containing silicate slags, nickel containing wastecatalysts, roasted zinc sulfide concentrate and aqueous reductionof As(V) to As(III) are included. Acetone and aqueous SO_2mixtures form #alpha#-hydroxy sulfonic acid, which is useful forleaching phosphate and uranium ores. Aspects related to leachingof some oxidic materials in organic solvents such as dimethylsulfoxide (DMSO), dimethyl formamide (DMF) and acetonitrile inthe presence of sulfur dioxide are also considered, since novelreactions in non-aqueous solvents may open up new opportunitiesfor the treatment of complex materials.