Stabilization of acid generating waste rock with fly ash – immobilization of arsenic under alkaline conditions
نویسندگان
چکیده
A fly ash was used to increase pH and decrease arsenic leaching from an acidic mine waste. Both the amended system as well as the control system was leached with ultra pure water. pH in the control increased from 1.7 to 2.7 at the end of the experiment while the pH in the amended system decreased from 12.6 to 11.5. compared to the control the initial concentrations of arsenic decreased with almost three orders of magnitude in the amended systems. A combination of co precipitation with iron and calcium arsenate precipitation were identified as the major arsenic immobilization mechanisms.
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