Role of starch and metabisuphite on pure pyrite and pyritic copper ore flotation

Depression of pyrite is very important in sulphide ore flotation. This paper investigates the role of non-toxic depressants on the flotation of pyrite. Starch and meta bisulphite were used as a depressant for pure pyrite sample and a pyritic copper ore at two different pHs values. pH was 6.5 and 10 in pure pyrite study while it was 6.9 and 12 in pyritic ore study. This study showed that metabisulphite is more effective at pH 6.5 or 6.9 than pH 10 or 12, while starch is more effective at pH 12. Also, higher dosages of meta bisulphite are required for depression of pyrite. Pure pyrite and pyritic copper ore study gave similar results.