Steel slags are the by-products of steel industries, which are
formed during reduction process of iron melting. The chemical composition of it
changes depending to the melting procedure. Its mineralogical composition also
varies based on the cooling procedure. Two different types of steel slag were
used as absorbing bed for various concentrations of Pb
$^{2+}$
ions in the form of lead chloride, and the concentrations of lead ions were
measured in the effluent by atomic absorption spectroscopy.
When Electric Arc Furnace Slag (EAFS) which is a basic crystalline
slag was used in the presence of various concentrations of
Pb
$^{2+}$
, ranging from 2 mg/l up to 10 mg/l, the
Pb
$^{2+}$
ions were leached out into the solution and its
concentration increased at the beginning of reaction but decreased dramatically
up to 48 hours that the reaction was continuing but with slower rate. Almost
the same thing happened when granulated blast furnace slag (GBFS), which is
also a basic slag but in the amorphous mineralogical form, was used as the
absorbing bed. The extent of ion release was much lower compared to EAFS but
the absorption of lead ions took place with the higher rates. Based on this
research, if EAF slag was used as absorbing bed for reduction of lead ions in
the industrial waters, it takes 24 hours to absorb 10 mg/l of lead ions, while
if blast furnace slag was used, maximum amounts of lead was absorbed in the
first thirty minutes of reaction.
