MINE WATER AND THE ENVIRONMENT, cilt.36, ss.255-263, 2017 (SCI İndekslerine Giren Dergi)
MINE WATER AND THE ENVIRONMENT
Pyrite ash (PA), a waste produced during the roasting of pyrite ores to produce sulfuric acid, was studied as a potential adsorbent for removing arsenic (As) from groundwater. The collected pyrite ash waste samples contained > 86 % iron (as Fe2O3). The results indicate that adsorption of As by PA was only slightly affected by initial pH at pH ae 9. Arsenate removal efficiency increased with the amount of adsorbent added over the range of 0.1-50 g/L. The As(V) removal increased with time, and 79 % removal was achieved within 1 h. Moreover, there was no significant change in As concentrations after 24 h. The adsorption process was best described by a second-order kinetic model. The adsorption of As(V) onto the PA was found to have followed the Langmuir isotherm. In batch studies, the maximum As(V) removal efficiency was 97 % at an adsorbent dose of 10 g/L, with an initial As(V) concentration of 300 A mu g/L. Thus, the PA was shown to be a suitable sorbent, reducing As from an initial level of 600 to < 10 mu g/L As(V), i.e., below the WHO limit for drinking water.