| abstract |
1. A METHOD OF RECOVERING BROMINE AS SODIUM BROMIDE AND ALSO PRODUCING SODIUM BICARBONATE FROM AT LEAST THE AQUEOUS PHASE OBTAINED FROM RECOVERY OF CATALYST METAL CARBONATE PRODUCT FROM TERE- OR ISOPHTHALIC ACID PROCESS RESIDUE CONTAINING WATER SOLUBLE SALTS OF BROMINE AND AT LEAST COBALT AS CATALYST METAL, CORROSION METALS INCLUDING IRON AND ACIDIC AND NEUTRAL AROMATIC COMPOUNDS BY TREATMENT OF SUCH RESIDUE WITH WATER IN AN AMOUNT OF 1.0-10.0 WEIGHT PARTS PER WEIGHT PART OF WATER AND WITH SODIUM BICARBONATE OR CARBONATE TO FORM A CATALYST METAL CARBONATE PRECIPITATE AND SEPARATING SUCH PRECIPITATE FROM THE RESULTING AQUEOUS PHASE, WHICH METHOD COMPRISES THERMALLY CONVERTING AT A TEMPERATURE IN THE RANGE OF 900-1000*C. THE SOLUTE CONTENT OF SAID AQUEOUS PHASE TO A SOLID MIXTURE CONTAINING SODIUM BROMIDE AND SODIUM CARBONATE AND WATER INSOLUBLE SOLIDS, LEACHING SAID SOLID MIXTURE WITN WATER IN AN AMOUNT TO FORM A SOLUTION OF ALL SODIUM BROMIDE AND SUBSTANTIALLY SATURATED SAID SOLUTION WITH RESPECT TO SODIUM CARBONATE, SEPARATING THE EXTRACT SOLUTION FROM INSOLUBLE SOLIDS, CONVERTING THE SODIUM CARBONATE IN SID EXTRACT SOLUTION TO PRECIPITATED SODIUM BICARBONATE BY REACTON WITH CARBON DIOXIDE IN THE PRESENCE OF SODIUM BROMIDE IN AN AMOUNT OF AT LEAST 10 WEIGHT PERCENT OF THE SOLUTION AT A TEMPERATURE IN THE RANGE OF AT LEAST 20*C. BUT NOT EXCEEDING THE TEMPERATURE OF REVERSING SAID CONVERSION OF CARBONATE TO BICARBONATE, SEPARATING SODIUM BICARBONATE PRECIPITATE FROM THE AQUEOUS SOLUTION OF SODIUM BROMIDE, WASHING THE RECOVERED PRECIPITATE WITH WATER, ADDING THE AQUEOUS WASH LIQUOR TO THE STEP OF DISSOLVING THE MIXTURE OF SODIUM BROMIDE AND SODIUM CARBONATE, CONCENTRATING SAID SEPARATED AQUEOUS SOLUTION OF SODIUM BROMIDE TO A SODIUM BROMIDE CONTENT OF 30 TO 45 WEIGHT PERCENT BY THE REMOVAL OF WATER FROM SAID COMPOSITE. |