Concentration of sylvite ores

Claim 1

IN A PROCESS FOR SEPARATING SYLVITE FROM SYLVINITE ORE BY FIRST PULPING THE COMMINUTED ORE IN AN AQUEOUS BRINE SATURATED WITH RESPECT TO THE ORE UNDER THE CONDITIONS OBTAINING, AND THEN FLOATING OFF SYLVITE BY SUBJECTING THE PULP TO A FLOTATION STEP INVOLVING THE USE OF A COLLECTING AGENT CONTAINING A MIXTURE OF ALKYL AND ALKENYL AMINE COMPONENTS SELECTED FROM THE GROUP CONSISTING OF PRIMARY ALIPHATIC AMINES CONTAINING LONG STRAIGHT CHAIN HYDROCARBON GROUPS AND THEIR WATER SOLUBLE ACID ADDITION SALTS WHERE THE FLOTATION STEP IS CARRIED OUT OVER A PERIOD OF TIME DURING WHICH THE TEMPERATURE OF THE FLOTATION PULP CHANGES, THE IMPROVEMENT COMPRISING MAINTAINING THE FLOTATION EFFICIENCY OF THE COLLECTING AGENT BY FIRST SELECTING AN AMINE MIXTURE WHICH HAS BEEN FOUND TO GIVE OPTIMUM RESULTS AT ONE TEMPERATURE AND THEN CHANGING THE RELATIVE AMOUNT OF THE ALKYL AND ALKENYL COMPONENTS OF THE AMINE MIXTURE IN ACCORDANCE WITH CHANGES OF TEMPERATURE OF THE FLOTATION PULP SO AS TO REDUCE THE IODINE NUMBER IN ACCORDANCE WITH AN INCREASE IN TEMPERATURE AND INCREASE THE IODINE NUMBER IN ACCORDANCE WITH A DECREASE IN TEMPERATURE.