ELIMINATION OF TOXIC ELEMENTS BY NATURAL AND SYNTHETIC ADSORBENTS

Abstract

The adsorption of Zn(II) and Cu(II) onto siderite (S) and kaolin (K) and adsorption of As(V) onto
bentonite (B) was studied. The chemical modification – precipitation of MnO2 on the kaolin (KM) and
siderite (SM) surface was used to improve the adsorption properties of natural materials for their
application in columns. In the batch tests the higher adsorption capacity was observed for the KM
sample. The binary solution of Zn(II)/Cu(II) was percolated through the columns filled with quartz sand
(QS) as a bearer of KM or SM. The effect of toxic elements removal reached in average 90 % for both
columns.
The adsorption of As(V) onto natural bentonite (B) and synthetic magnetic particles (MP) was studied
by batch as well as column tests. Whereas the B sample did not perform good adsorption properties in
batch test, in dynamic conditions its effect was comparable with MP. The effect of As(V) removal was
studied in a number of series with different materials beddings and cycles repetitions. The results
showed that the most effective was the column filled with QS+B+MP containing more coarse-grained
fraction of bentonite. In the second cycle its removal effect reached 60 % of As(V) elimination from the
solution.