Process for hydrogen cyanide production

Claim 1

A PROCESS FOR THE CONVERSION OF AMMONIA TO HYDROGEN CYANIDE WHICH COMPRISES PASSING A REACTANT GAS MIXTURE OF HYDROCARBON, OXYGEN, AND AMMONIA THROUGH AN ELONGATED PREHEATING ZONE HAVING AN INSIDE DIAMETER BETWEEN 0.05 AND 0.5 INCHES, INTRODUCING PREHEATED REACTANT GAS THEREFROM INTO A CONFINED REACTION ZONE, ESTABLISHING AND MAINTAINING A FLAME REACTION THEREIN AT THE OUTLET OF SAID PREHEATING ZONE FORMING PRODUCT GASES CONTAINING HYDROGEN CYANDIE, IMMEDIATELY REVERSING THE FLOW DIRECTION OF THE REACTING GASES IN SAID CONFINED REACTION ZONE THEREBY SURROUNDING SAID FLAME WITH A FLOW OF SAID PRODUCT GAS SO AS TO PROVIDE A DIRECT COUNTERCURRENT HEAT EXCHANGE BETWEEN SAID PRODUCT GAS AND SAID REACTANT GAS ENTERING SAID REACTION ZONE, PASSING SAID PRODUCT GAS FROM SAID REACTION ZONE THROUGH A PRODUCT COOLING ZONE SURROUNDING SAID PREHEATING ZONE IN DIRECT COUNTERCURRENT HEAT EXCHANGE RALATION TO SAID REACTANT GAS THEREBY TERMINATING SAID FLAME REACTION AND FORMING SAID PREHEATING REACTANT GAS MIXTURE AD COOLED PRODUCT GASES, CONTROLLING THE RATE OF INTRODUCTION OF SAID REACTANT GAS MIXTURE INTO SAID PREHEATING ZONE SO THAT THE PRODUCT OF THE REACTANT GAS VELOCITY IN FEET PER SECOND CALCULATED TO STANDARD CONDITIONS AND THE SQUARE ROOT OF THE INSIDE DIAMETER OF SAID PREHEATING ZONE IN INCHES IS BETWEEN A VALUE OF 1.5 AND 4.0 TO MAINTAIN THE CONVERSION OF AMMONIA TO HYDROGEN CYANIDE AT A MAXIMUM, AND REMOVING SAID COOLED PRODUCT GAS CONTAINING HYDROGEN CYANIDE FROM SAID PRODUCT COOLING ZONE.