Comparison of heavy metal removals from aqueous solutions by chemical precipitation and characteristics of precipitates

Typical chemical precipitation methods using lime (Ca(OH)2), soda ash (Na2CO3) and sodium sulfide (Na2S) for removals of heavy metals (i.e. Zn (II), Cu (II) and Pb (II)) from aqueous solutions were compared by jar tests. A focus was especially given to particle size differences and chemical phase conversion of precipitates. A removal of 99.99% from aqueous solutions with three precipitants was achieved for copper and zinc at an initial...