The Oxidation of Ferrous Sulphate by Molecular Oxygen under Zinc Pressure-Leach Conditions 锌压浸条件下分子氧氧化硫酸亚铁.pdf

HydrometaUurgy, 22 (1989) 101-119 101 Elsevier Science Publishers B.V., Amsterdam - - Printed in The Netherlands The Oxidation of Ferrous Sulphate by Molecular Oxygen under Zinc Pressure-Leach Conditions D.B. DREISINGER and E. PETERS Department of Metals and Materials Engineering, University of British Columbia, 309-6350 Stores Road, Vancouver, B.C. V6T 1 W5 (Canada) (Received October 9, 1987; revised and accepted April 25, 1988 ) ABSTRACT Dreisinger, D.B. and Peters, E., 1989. The oxidation of ferrous sulphate by molecular oxygen under zinc pressure-leach conditions. Hydrometallurgy, 22: 101-119. The oxidation of ferrous sulphate by molecular oxygen under zinc pressure-leach conditions has been investigated. The effects of the variables temperature, acid concentration, zinc sulphate concentration, copper sulphate concentration and the addition of various sulphate salts were stud- ied. An overall equation to describe the rate of ferrous oxidation was proposed and is included below. This equation accounts for: (1) the higher reactivity of the ferrous sulphate ion pair relative to the free ferrous ion; (2) the catalysis of the reaction by copper; and (3) the activation energy of the reaction: ~d[Fe~II~ ] (3 6× 10-5[Fe2+ ]2Po2+5.2× 10-4[Fe 2+ ] [FeSO4]Po2 + ¥ =\ 166× 10-~ [FeSO412P°2 ) (10 + 50 [CuS04]°~) {exp[ -9660( 1 42~.15)] } INTRODUCTION The pressure leaching of zinc-sulphide concentrates in dilute sulphuric acid using molecular oxygen has become an established process for zinc extraction. The first commercial autoclave was installed at Trail, B.C. (Canada) in 1981 alongside a conventional roast-leach plant. The chemistry of the pressure leach has been