Process of preparing bis-(3, 5, 6-trichloro-2-hydroxyphenyl) methane

Claim 1

IN THE PROCESS FOR PREPARING BIS-(3,5,6-TRICHLORO-2HYDROXYPHENYL) METHANE BY CONDENSING 2,4,5-TRICHLOROPHENOL WITH A FORMALDEHYDE-YIELDING SUBSTANCE AT ELEVATED TEMPERATURES IN THE PRESENCE OF A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF SULFURIC ACID HAVING AT LEAST ABOUT 93% H2SO4 CONTENT BY WEIGHT AND OLEUM, THE IMPROVEMENT WHICH COMPRISES CONDUCTING THE CONDENSATION REACTION IN THE PRESENCE OF A SUFFICIENT AMOUNT OF AT LEAST ONE SOLVENT SELECTED FROM THE GROUP CONSIST-ING OF SATURATED POLYHALOGENATED DERIVATIVES OF METHANE, ETHANE AND PROPANE AND THE CORRESPONDING UNSATURATED POLYHALOGENATED HYDROCARBONS WHICH ARE FREE OF HYDROGEN BOUND TO A CARBON ATOM WHICH ITSELF IS UNITED TO ANOTHER CARBON ATOM BY A DOUBLE BOND SO AS TO MAINTAIN THE CONDENSATION PRODUCT SUBSTANTIALLY IN SOLUTION, SEPATHE SOLVENT THROUGHOUT THE CONDENSATION REACTION, SEPA RATING THE RESULTING LOWER LAYER WHICH COMPRISES A CONCENTRATED SOLUTION OF SULFURIC ACID, ADDING WATER TO THE REMAINING SOLVENT LAYER CONTAINING THE REACTION PRODUCT, PHYSICALLY SEPARATING THE SOLVENT, AND FILTERING THE BIS(3,5,6-TRICHLORO-2-HYDROXYPHENYL) METHANE FROM THE RESULTING WATER SUSPENSION.