2.1 Material preparation and leaching experiments
The local clay was obtained from Ozoro (6.24oN,
5.55oE) in Delta State Nigeria. The characterization
of this clay by Orugba et al., (2014) revealed Ozoro clay has 33.90% of
alumina making it a very viable source of the ore. The clay was soaked
in water for two days in order to ease the removal of debris and stony
materials. The dissolved clay was properly sieved and sun-dried for 24
hours then oven dried at 60oC for 18 hours to
aggregate the particles. The clay samples were subjected to heat
activation in a muffle furnace at different temperatures ranging from
400oC to 900oC for a period of
1hour. The activated clay samples were ground to the same particle size
of 0.045mm and properly labeled and were subjected to leaching.
In the leaching experiments, 20g of the activated clay was weighed into
an already determined volume of the acid and heated in a round bottom
flask based on the liquid-solid ratio of each run for a period of
30minutes. At the end of the period, 2ml of each sample was collected
and analyzed for alumina iron using the Atomic Adsorption Spectra (AAS).