Method of producing magnesium hydroxide having variable particle sizes

Claim 1

IN THE PROCESS OF PRODUCING MAGNESIUM HYDROXIDE BY THE REACTION OF A MANGESIUM HALIDE-CONTAINING SOLUTION WITH A COMPOUND SELECTED FROM THE CLASS CONSISTING AT QUICKLIME AND DOLIME, THE IMPROVEMENT WHICH COMPRISES ADDING SAID COMPOUND SELECTED FROM THE GROUP CONSISTING OF QUICKLIME AND DOLIME IN AN AMOUNT SUFFICIENT TO REACT WITH FROM ABOUT 10% TO ABOUT 90% OF THE MAGNESIUM VALUES CONTAINED IN THE MAGNESIUM HALIDE SOLUTION IN THE PRESENCE OF A SOLUBLE BORON SALT IN AMOUNTS SUFFICIENT TO SUPPLY FROM 20 TO 500 MILLIGRAMS OF BORON PER LITER,PRECIPITATING A RELATIVELY COARSE MG(OH)2 FRACTION, SEPARATING SAID COARSE FRACTION OF MG(OH)2 SLUDGE FROM THE RESULTANT SUPERNATANT MAGNESIUM HALIDE SOLUTION REDUCED IN BOTH MAGNESIUM AND BORON VALUES, REACTING SAID SUPERNATANT MAGNESIUM HALIDE SOLUTION WITH AN ADDITIONAL QUANTITY OF A COMPOUND SELECTED FROM THE GROUP CONSISTING OF DOLIME AND QUICKLIME IN AMOUNTS SUFFICIENT TO PRECIPITATE NO MORE THAN 95 TO 99% OF THE REMAINING MAGNESIUM IN SAID SUPERNATENT MAGNESIUM HALIDE SOLUTION PRECIPITATING A MAGNESIUM HYDROXIDE FRACTION HAVING A FINER PARTICLE SIZE THAN THE INITIAL FRACTION OF MAGNESIUM HYDROXIDE AND SEPARATING SAID FINER MAGNESIUM HYDROXIDE FRACTION FROM SAID MOTHER LIQUOR WHICH IS SUBSTANTIALLY REDUCED IN MAGNESIUM VALUES.