Abstract:
Kaolinite is one of the major clay types which can be used to remove ions from the water by
using its adsorption capacity (Krishna and Gupta, 2006). Though several clay types are found in
Sri Lanka, significant use of them for value addition purposes is not practiced.By considering
that fact and the unique ability of kaolinite to remove ions from water is targeted throughout this
research.Meetiyagoda kaolinite is used as clay type, because it is currently used only as a raw
material for ceramic industry and none of the researches have been conducted to investigate its
ability to remove ions from water. Therefore the ultimate goal of this study is to fill that gap and
develop a value added product from Meetiyagodakaolonite. This research focuses on removing
arsenic (V) from water while modifying kaolinite surface using Humic Acid in order to enhance
its adsorption capacity and measuring the removal amount of arsenic (V) by changing amount
of clay, concentration of arsenic (V) and pH.
Methodology
The purified Meetiyagoda kaolinite sample was taken from Meetiyagoda clay refinery and it
was dried, ground and sieved to obtain 75µmparticle size.This particle size was preferred
because, when particle size gets smallest it increases the surface area of kaolinite which results
in more adsorption of arsenic on to kaolinite surface. Humic acid was prepared by mixing dried
homo-ionized clay
was prepared using kaolinite and 1M CaCl2.Previously prepared humic acid was readjusted to
homo-ionized clay was added to pH neutral humic
acid and the humic acid-clay suspension was incubated in mechanical shaker, then the
suspension was centrifuged. Finally the humic acid coated clay sample was dried and used. The
effect of arsenic removal by humic acid modified Meetiyagoda kaolinite was analysed while
changing amount of humic acid modified clay, initial arsenic concentration and pH of the
solution using Varian 700ES ICP-OES Atomic Absorption Spcetrophotometer.
