Method of making ammonium sulphate

Claim 1

THE METHOD OF MAKING AMMONIUM SULFATE WHICH COMPRISES; ROASTING AN ORE CONTAINING SULPHIDES OF IRON, ZINC AND COPPER AT SUCH A TEMPERATURE THAT APPROXIMATELY ONE-HALF OF THE COPPERZINC CONTENT SHALL BE PRESENT IN THE CALCINES AS WATER SOLUBLE SULPHATE; LEACHING THE CALCINES TO PRODUCE A RESIDUE INSOLUBLE IN WATER AND A SOLUTION OF SULPHATES OF IRON, ZINC, AND COPPER; OXIDIZING SAID SOLUTION AND PRECIPITATING THE CONTAINED IRON BY THE ADDITION OF THE NECESSARY AMOUNT OF A BASIC AMMONIA COMPOUND, SELECTED FROM THE GROUP CONTAINING THE CARBONATE, HYDROXIDE AND SULPHIDE OF AMMONIA; REMOVING THE RESULTING PRECIPITATE OF FERRIC HYDROXIDE AND COMMINGLING THE RESULTANT SOLUTION WITH SUFFICIENT WATER-SOLUBLE SULPHIDE TO PRECIPITATE THE RESIDENT COPPER AS COPPER SULPHIDE; SEPARATING SAID COPPER SULPHIDE AND RESERVING THE RESULTANT SOLUTION OF ZINC, AND AMMONIUM SULPHATE FOR FURTHER TREATMENT; RE-ROASTING THE LEACHED RESIDUE FROM THE FIRST ROASTING STEP AT A TEMPERATURE SUFFICIENTLY HIGH TO ENSURE COMPLETE OXIDATION OF THE RESIDENT SULPHIDES; COMMINGLING SAID DEAD-ROASTED CALCINES WITH CARBONATED AMMONIA WATER IN SUFFICIENT AMOUNT TO PRODUCE COMPLETE SOLUTION OF THE STILL RESIDENT ZINC AND COPPER; SEPARATING THE INSOLUBLE RESIDUE FROM THE COPPER-ZINC AMMONIUM CARBONATE SOLUTION; PURIFYING SAID SOLUTION FROM COPPER BY ADDING THE REQUISITE AMOUNT OF A SOLUBLE SUPHIDE AND SEPARATING THE RESULTANT PRECIPITATE OF COPPER SULPHIDE; COMMINGLING THE RESULTANT ZINC SOLUTION WITH THE ONE PREVIOUSLY MADE AND RESERVED FOR FUTURE TREATMENT AND SEPERATING THE ZINC CARBONATE PRODUCED THEREBY; COMMINGLING THE RESULTANT ZINC CONTAINING SOLUTION OF AMMONIUM SULPHATE WITH GAS FROM THE ROASTING STEPS AND WITH SUFFICIENT BASIC AMMONIA COMPOUND, SELECTED FROM THE GROUP PREVIOUSLY DEFINED, TO REACT THEREWITH FORMING ADDITIONAL SULPHATE OF AMMONIA AND ELEMENTAL SULPHUR; SEPARATING SAID SULPHUR; PURIFYING THE RESULTANT AMMONIUM SULPHATE SOLUTION FROM ZINC BY A FURTHER ADDITION OF A SOLUBLE SULPHIDE AND SEPARATING THE PRECIPITATED ZINC SULPHIDE THUS PRODUCED FROM THE RESULTANT SOLUTION OF AMMONIUM SULPHATE.

Claim 2

THE METHOD OF MAKING AMMONIUM SULFATE WHICH COMPRISES; ROASTING AN ORE CONTAINING SULPHIDES OF IRON, ZINC AND COPPER AT SUCH A TEMPERATURE THAT APPROXIMATELY ONE-HALF OF THE COPPERZINC CONTENT SHALL BE PRESENT IN THE CALCINES AS WATER SOLUBLE SULPHATE; LEACHING THE CALCINES TO PRODUCE A RESIDUE INSOLUBLE IN WATER AND A SOLUTION OF SULPHATES OF IRON, ZINC, AND COPPER; OXIDIZING SAID SOLUTION AND PRECIPITATING THE CONTAINED IRON BY THE ADDITION OF THE NECESSARY AMOUNT OF A BASIC AMMONIA COMPOUND, SELECTED FROM THE GROUP CONTAINING THE CARBONATE, HYDROXIDE AND SULPHIDE OF AMMONIA; REMOVING THE RESULTING PRECIPITATE OF FERRIC HYDROXIDE AND COMMINGLING THE RESULTANT SOLUTION WITH SUFFICIENT WATER-SOLUBLE SULPHIDE TO PRECIPITATE THE RESIDENT COPPER AS COPPER SULPHIDE; SEPARATING SAID COPPER SULPHIDE AND RESERVING THE RESULTANT SOLUTION OF ZINC, AND AMMONIUM SULPHATE FOR FURTHER TREATMENT; RE-ROASTING THE LEACHED RESIDUE FROM THE FIRST ROASTING STEP AT A TEMPERATURE SUFFICIENTLY HIGH TO ENSURE COMPLETE OXIDATION OF THE RESIDENT SULPHIDES; COMMINGLING SAID DEAD-ROASTED CALCINES WITH CARBONATED AMMONIA WATER IN SUFFICIENT AMOUNT TO PRODUCE COMPLETE SOLUTION OF THE STILL RESIDENT ZINC AND COPPER; SEPARATING THE INSOLUBLE RESIDUE FROM THE COPPER-ZINC AMMONIUM CARBONATE SOLUTION; PURIFYING SAID SOLUTION FROM COPPER BY ADDING THE REQUISITE AMOUNT OF A SOLUBLE SUPHIDE AND SEPARATING THE RESULTANT PRECIPITATE OF COPPER SULPHIDE; COMMINGLING THE RESULTANT ZINC SOLUTION WITH THE ONE PREVIOUSLY MADE AND RESERVED FOR FUTURE TREATMENT AND SEPERATING THE ZINC CARBONATE PRODUCED THEREBY; COMMINGLING THE RESULTANT ZINC CONTAINING SOLUTION OF AMMONIUM SULPHATE WITH GAS FROM THE ROASTING STEPS AND WITH SUFFICIENT BASIC AMMONIA COMPOUND, SELECTED FROM THE GROUP PREVIOUSLY DEFINED, TO REACT THEREWITH FORMING ADDITIONAL SULPHATE OF AMMONIA AND ELEMENTAL SULPHUR; SEPARATING SAID SULPHUR; PURIFYING THE RESULTANT AMMONIUM SULPHATE SOLUTION FROM ZINC BY A FURTHER ADDITION OF A SOLUBLE SULPHIDE AND SEPARATING THE PRECIPITATED ZINC SULPHIDE THUS PRODUCED FROM THE RESULTANT SOLUTION OF AMMONIUM SULPHATE.