Purification of meta-nitro-paratoluidine

Claim 1

A PROCESS FOR THE PURIFICATION OF META NITRO PARA TOLUIDINE COMPRISING ESSENTIALLY THE FOLLOWING STEPS: DISPERSING A WATER-CONTAINING META NITRO PARA TOLUIDINE CRUDE IN A VOLATILE AROMATIC HYDROCARBON SOLVENT, SAID SOLVENT BEING IMMISCIBLE WITH WATER, CHEMICALLY INERT TO THE META NITRO PARA TOLUIDINE AND CAPABLE OF SELECTIVELY DISSOLVING THE META NITRO PARA TOLUIDINE, REMOVING SUBSTANTIALLY ALL THE WATER FROM THE RESULTING DISPERSION BY DISTILLING THEREFROM AND CONDENSING A WATER-SOLVENT MIXTURE, SEPARATING AND RETURNING THE AROMATIC SOLVENT PORTION OF SAID CONDENSATE TO THE DISTILLAND, CONTINUING THE DISTILLATION UNTIL THE SAID DISTILLAND BECOMES SUBSTANTIALLY ANHYDROUS, INCORPORATING INORGANIC FILTER AGENTS OF HIGH SPECIFIC SURFACE WITH THE DISTILLAND, REMOVING THE INSOLUBLE SUSPENDED MATTER FROM SAID HOT DISTILLAND, SUBJECTING THE CLARIFIED FILTRATE TO A TEMPERATURE AT LEAST BELOW 10* C. BY RAPID EXPOSURE TO A FINELY DIVIDED SOLID COOLANT IN AQUEOUS CARRIER THEREFOR, THEREBY RAPIDLY CRYSTALLIZING THE META NITRO PARA TOLUIDINE FROM THE SOLVENT SOLUTION IN MINUTE CRYSTALS, REMOVING THE SOLVENT FROM THE CRYSTALS AT A TEMPERATURE BELOW ABOUT 48* C., AND THEREAFTER RECOVERING THE PURIFIED META NITRO PARA TOLUIDINE IN THE SAID MINUTE CRYSTAL FORM FROM THE RESIDUAL AQUEOUS MEDIA IN A SOLVENT-FREE WATER-WETTED STATE.