Sodium cakbonate manufacture

Claim 1

A PROCESS FOR MAKING SODIUM CARBONATE MONOHYDRATE WHICH COMPRISES: REACTING AN AQUEOUS SODIUM CARBONATE LIQUOR WITH AN AQUEOUS CAUSTIC SODA LIQUOR CONTAINING AT LEAST 56% AND NOT MORE THAN ABOUT 63% BY WEIGHT OF SODIUM HYDROXIDE WHEREBY SODIUM CARBONATE MONOHYDRATE IS PRECIPITATED WITHOUT APPLICATION OF ADDITIONAL HEAT, THE AMOUNT OF SAID CAUSTIC SODA LIQUOR AND THE CONCENTRATION OF SAID SODIUM CARBONATE LIQUOR BEING SUCH THAT THE MOTHER LIQIOR RESULTING FROM THE PRECIPITATION CONTAINS LESS THAN 20% BY WEIGHT OF SODIUM HYDROXIDE AND MORE THAN 6% BY WEIGHT OF SIODIUM CARBONATE; SEPARATING SAID PRECIPITATED SODIUM CARBONATE MONOHYDRATE; REACTING SAID MOTHER LIQUOR AT A TEMPERATURE ABOVE 30*C. WITH SUFFICIENT OF A CARBON DIOXIDECONTAINING GAS TO GIVE A CARBONATED LIQUOR IN WHICH SUBSTANTIALLY ALL SODIUM HYDROXIDE HAS BEEN CONVERTED TO SODIUM CARBONATE; REACTING SAID CARBONATED LIQUOR WITH AN AQUEOUS CAUSTIC SODA LIQUOR CONTAINING AT LEAST 56% AND NOT MORE THAN ABOUT 63% BY WEIGHT OF SODIUM HYDROXIDE WHEREBY FURTHER SODIUM CARBONATE MONOOHYDRATE IS PRECIPITATED WITHOUT APPLICATION OF ADDITIONAL HEAT; REMOVING FROM THE PROCESS WATER VAPORIZED FROM SAID LIQUOORS BY THE HEAT WHICH IS LIBERATED DURING SAID CARBONATION AND PRECIPITATION REACTIONS; AND SEPARATING SAID FURTHER PRECIPITATED SODIUM CARBONATE MONOHYDRATE.