Froth flotation

Abstract

A process for recovering phosphate values from a finely divided ore containing the phosphate values and gangue such as an ore containing apatite, calcite and dolomite, by froth flotation includes the steps of suspending the finely divided ore containing the phosphate values and the gangue in a liquid at a pH of greater than 7; adding to the suspension a froth flotation collector comprising a tall oil fatty acid and an emulsifier for the tall oil fatty acid selected from alkylphenylalkoxylates having the formula: ##STR1## wherein: n is an integer from 8-10 inclusive; m is an integer from 10-20 inclusive; and alkyl is --CH.sub.2 --CH.sub.2 -- or ##STR2## the froth flotation collector comprising 80-99% by weight of the collector of the tall oil fatty acid and 20 to 1% by weight of the collector of the emulsifier; introducing a gas such as air into the liquid to produce a froth containing the phosphate values and leaving suspended the other solid gangue; and recovering the phosphate values.

Dependencies are inferred from the claim text.