PROCESS FOR PREPARATING HYDRATED ALUMINA IN THE FORM OF SPHERICAL PARTICLES BY HOMOGENEOUS PRECIPITATION

摘要

A process for preparing hydrated alumina consisting essentially of spherical particles having a narrow granulometric distribution (polydispersion index dw/dn/=2) starting from aqueous solution of aluminum sulphate, the molar ratio SO4=/Al3+ being greater than 1, by homogeneous precipitation in the presence of cationic polyelectrolytes, which are soluble under the reaction conditions and have a mean molecular weight higher than one million and an ionicity, deriving from the cationic groups present in the polyelectrolyte, of at least 3 milliequivalents/gram.