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Journal of Material Sciences
ISSN: 2321-6212
I n t e r n a t i o n a l C o n f e r e n c e o n
Metal, Mining and
Magnetic Materials
N o v e m b e r 0 1 - 0 2 , 2 0 1 8
P a r i s , F r a n c e
Metal and Magnetism 2018
Evaluating the recovery of iron and aluminium from acid mine
drainage by precipitation
Brian Mwewa, Sehliselo Ndlovu and Geoffrey Simate
University of the Witwatersrand Johannesburg, South Africa
T
he wastes generated from both operational and abandoned coal and metal mining are an environmental concern. These
wastes, including acid mine drainage (AMD), are treated to abate the devastating effects they have on the environment before
disposal. The mining-metal industry and environmental agencies are aware of the opportunities to recover valuable resources
from AMD to subsidize the treatment cost. This work examined the potential of recovering iron and aluminium from coal AMD
by an oxidation-precipitation process. The co-precipitation of iron and aluminium was conducted at pH 5, 6 and 7 to evaluate
the recovery of metals and the associated precipitate purities. The results showed that precipitation at pH 5 yielded iron and
aluminium recovery of 99% and 96%, respectively. An increase in pH from 5 increased the recovery of aluminium with recoveries
of 98% and 99% at pH 6 and 7, respectively. However, the precipitate purity deteriorated due to co-precipitation of other impurities.
The least precipitate purity was observed at pH 7 with co-precipitation of manganese and cerium observed. Based on the results
obtained, the iron and aluminium precipitate obtained at pH 5, with minimal co-precipitation of other impurities can be used in the
recovery of iron and aluminium based coagulants. This process, which can easily be incorporated into existing AMD treatment
plants, does not only reduce the sludge disposal problems but also creates revenue from a waste.
sirbhimself@yahoo.co.ukJ Mat. Sci. 2018, Volume:6
DOI: 10.4172/2321-6212-C7-033