Inorganic perbromide compositions and methods of use thereof

A leaching solution adapted for leaching a precious metal selected from the group consisting of gold, silver, platinum, palladium or mixtures thereof from a source containing said precious metal, said leaching solution having a pH of between about 2 and about 10 and containing between about 0.01% and about 1% by weight equivalent molecular bromine, between about 0.01% and about 1% by weight bromide ion, and between about 0.005% and about 15% by weight total halide ion.

An aqueous composition comprising bromide ion, perbromide ion, molecular bromine, at least about 2% by weight bromate ion, and a metal ion selected from the group consisting of alkali metal and alkaline earth metal, the equivalent molecular bromine content of the composition being between about 10% and about 40% by weight and the ratio of the molar concentration of bromate ion to the sum of the molar concentrations of molecular bromine and perbromide ion in the composition being between about 0.05 and about 0.8.

A composition the formulation of which comprises water, at least about 25% by weight bromine, between about 4% and about 30% by weight hydrobromic acid, and between about 4% and about 15% by weight of a metal bromide selected from the group consisting of lithium bromide, sodium bromide, potassium bromide and calcium bromide, said formulation comprising a molar excess of bromide ion over bromine of at least about 30%, said composition having a pH of not greater than about 1.0.

A composition the formulation of which comprises between about 10% and about 40% by weight bromine, between 4% and about 20% by weight of a metal bromide selected from the group consisting of lithium bromide, sodium bromide, potassium bromide and calcium bromide, between about 5% and about 24% by weight hydrobromic acid, and at least about 10% by weight of an alcohol or a lower organic acid.

A composition the formulation of which comprises water, at least about 25% by weight bromine, at least about 4% by weight hydrochloric acid, and between about 10% and about 15% by weight sodium bromide, said formulation comprising a molar excess of halide ion over bromine of at least about 30%, said composition having a weight ratio of water to NaBr of not less than about 4.0 and a pH of not greater than about 1.0.

A composition whose formulation comprises water, at least about 25% by weight bromine, at least about 10% by weight hydrobromic acid, and at least about 5% by weight calcium bromide, said formulation comprising a molar excess of bromide ion over bromine of at least about 30%, said composition having a pH of not greater than about 1.0.

A composition the formulation of which comprises at least about 15% by weight bromine, between about 15% and about 40% by weight HBr, and between about 40% and about 60% by organic solvent.

A composition the formulation of which comprises water, at least about 25% bromine, and between about 30% and about 40% by weight HBr.

A process for producing an aqueous leachate containing a precious metal selected from the group consisting of gold, silver, platinum, palladium or mixtures thereof from a source thereof comprising adding to said source an aqueous bromine leaching solution containing between about 0.01% and about 20% by weight equivalent molecular bromine, between about 0.005% and about 20% by weight bromide ion, and between about 0.005% and about 30% by weight total halid ion, thereby producing said queous leachate containing the precious metal.