Abstract: A method for producing halide brine wherein an alkali and a reducing agent are added to an aqueous fluid having a density greater than 8.30 lb/gal., (0.996 kg/L) water, waste water or sea water for example. The resulting fluid is then contacted with a halogen to form a halide brine. The reaction occurs in a conventional reactor such as a mixing tank.

Abstract: A method for regenerating a used halide fluid comprising a density greater than 9.0 lbs/gal. and containing both soluble and insoluble impurities. This method comprises the steps of (1) adding acid to the used halide fluid so that the pH is within a range of approximately 0 to 10.0; (2) contacting the used halide fluid with halogen to increase the density to at least 10.0 lbs./gal., adjust the desired true crystallization temperature of the fluid and oxidize soluble impurities; (3) adding a reducing agent while maintaining the temperature at a minimum of 10° C.; (4) contacting the fluid with an alkali to neutralize excess acid; and (5) separating any suspended solid impurities from the fluid.

Abstract: A method for producing halide brine wherein an alkali and a reducing agent are added to an aqueous fluid having a density greater than 8.30 lb/gal., (0.996 kg/L) water, waste water or sea water for example. The resulting fluid is then contacted with a halogen to form a halide brine. The reaction occurs in a conventional reactor such as a mixing tank.

Abstract: A method for regenerating a used halide fluid comprising a density greater than 9.0 lbs/gal. and containing both soluble and insoluble impurities. This method comprises the steps of (1) adding acid to the used halide fluid so that the pH is within a range of approximately 0 to 10.0; (2) contacting the used halide fluid with halogen to increase the density to at least 10.0 lbs./gal., adjust the desired true crystallization temperature of the fluid and oxidize soluble impurities; (3) adding a reducing agent while maintaining the temperature at a minimum of 10° C.; (4) contacting the fluid with an alkali to neutralize excess acid; and (5) separating any suspended solid impurities from the fluid.

Abstract: A method for making zinc bromide from metallic zinc and bromine comprising contacting zinc with bromine dissolved in a reaction solvent containing a metal halide salt. During the practice of this method, the reaction temperature is maintained at less than 60.degree. C. The reaction solvent preferably comprises an alkali, alkaline earth or transition metal halide and the halide salt preferably comprises a chloride or a bromide. One preferred method includes the step of recirculating the zinc bromide product stream back to the reaction vessel. The reaction vessel can comprise either a one stage or a multiple stage reactor. The resulting product stream comprises a high density zinc bromide solution.

Abstract: A process is disclosed for removing colloidal and non-colloidal humic matter from an aqueous solution of phosphoric acid, the process comprising (a) treating the phosphoric acid solution with a flocculant to flocculate the humic matter, (b) adding to the aqueous solution an effective amount of a phenol compound in order to destabilize the colloidal humic matter contained in the solution and to aid in the formation of froth, and (c) separating the humic matter from the solution by froth flotation.

Abstract: Nickel is selectively leached efficiently and rapidly from Ni-Cu-Fe-S matte under oxidizing conditions at ordinary pressure by controlling in combination the following variables: (1) the acid-to-copper mole ratio in the leaching solution, (2) the temperature, and (3) the sulfur content of the matte, whereby an enriched nickel solution is obtained low in copper and iron.

Abstract: A method is provided for leaching comminuted nickeliferous sulfide matte containing by weight about 20% to 75% nickel, about 5% to 50% copper, non-stoichiometric sulfur in the range of over 4% to about 20%, over 0.5% to about 15 or 20% iron, the sum of the nickel, copper and sulfur contents being at least about 80% of the matte composition, with the balance gangue or slag and incidental impurities.The matte, because of the iron content, is first granulated by quenching molten matte from a temperature at least about 10.degree.C above its solidus-liquidus temperature but below its boiling point, following which the matte is comminuted and subjected to atmospheric leaching to dissolve nickel selectively therefrom using a spent copper electrolyte solution containing sulfuric acid having a pH ranging up to about 2 while aerating said solution to cause the pH to rise to above 5 and effect substantial precipitation of copper and iron.

Abstract: A method is provided for removing trace amounts of selenium from acid leach solutions containing over 2 ppm of total selenium comprising either Se(IV) and/or Se(VI) obtained during the pressure oxidation leaching of metal sulfide concentrate comprising forming a slurry of said acid solution with comminuted metal sulfide concentrate, said slurry containing at least two grams of a metal ion as metal hydroxide per liter of solution and then subjecting said slurry to agitation at a temperature of at least about 185.degree.C at a pressure of a least about 160 psig, whereby to reduce the total selenium content of said solution to less than about 2 ppm.