Catalytic hydrogenation of dinitroaromatic compounds

Claim 1

A PROCESS FOR THE CATALYTIC HYDROGEN REDUCTION OF AN AROMATIC DINITRO COMPOUND TO FORM THE CORRESPONDING DIAMINE COMPOUND WHICH COMPRISES RAPIDLY AGITATING AT TEMPERATURES WITHIN THE RANGE OF ABOUT 40* TO 400* C. AN AQUEOUS SUSPENSION OF A CATALYST SELECTED FROM THE GROUP CONSISTING OF PALLADIUM AND PLATINUM, INTRODUCING HYDROGEN AT ATMOSPHERIC TO SOMEWHAT ELEVATED PRESSURE AND A WATER-IMMISCIBLE DINITRO COMPOUND SELECTED FROM THE GROUP CONSISTING OF DINITROBENZENE, DINITROTOLUENE AND DINITROETHYLBENZENE INTO SAID SUSPENSION SLOWLY AT CORRELATED RATES WHICH PROVIDE FOR REDUCTION OF SAID DINITRO COMPOUND TO THE CORRESPONDING DIAMINE COMPOUND SUBSTANTIALLY AS RAPIDLY AS THE DINITRO COMPOUND IS ADDED, THE RATE OF INTRODUCTION OF SAID DINITRO COMPOUND BEING SUCH THAT NOT MORE THAN ABOUT 10% OF THE TOTAL DINITRO COMPOUND TO BE REDUCED IS PRESENT IN THE SUSPENSION AT ANY GIVEN TIME, MAINTAINING THE TEMPERATURE OF THE REACTION MASS WITHIN THE RANGE OF ABOUT 40* TO 100* C. DURING THE REDUCTION OF SAID DINITRO COMPOUND AND PROVIDING SUFFICIENT WATER IN THE REACTION MASS TO AT LEAST EQUAL THE WEIGHT OF DINITRO COMPOUND PRESENT AT ANY TIME AND SUFFICIENT TO MAINTAIN THE DIAMINE COMPOUND IN SOLUTION, AND THEN RECOVERING THE DIAMINE COMPOUND FORMED.