Collect. Czech. Chem. Commun. 1982, 47, 3362-3370

Precipitation and filtration of zinc, magnesium, copper and aluminium hydroxides

Otakar Söhnel and Eva Matějčková

Chemopetrol, Research Institute of Inorganic Chemistry, 400 60 Ústí nad Labem


Filtration properties of batchwise precipitated suspensions of Zn(OH)2, Mg(OH)2 and Cu(OH)2 and continuously precipitated Al(OH)3 were studied. For batchwise precipitated suspensions was verified the theoretically predicted dependence of specific filtration resistance on initial supersaturation and for the continuously precipitated Al(OH)3 the relation between the specific filtration resistance and the mean residence time of suspension in the reactor. Dependences were also recorded between the bed porosity and concentration of precipitated solutions, specific filtration resistance and used filtration pressure and the effect of aging of the batchwise precipitated suspension of Mg(OH)2on its filtration properties. The used CST method for determination of filtration characteristics of Zn(OH)2 suspension was also studied.