| Summary: | Degree of Master of Science in Chemistry in the School of Pure and Applied Sciences of Kenyatta University, May 2015. More than two thirds of the earth is covered by water bodies but 97.5% of all water on earth is salt water, leaving only 2.5% as fresh water. Approximately 70% of that fresh water is frozen in the icecaps of Antarctica and Greenland; most of the remainder is present as soil moisture, or lies in deep underground aquifers as groundwater thus making it inaccessible for human use. Less than 1% of all water on earth is accessible for direct human uses. In Kenya, only 1.9% of land coverage is occupied by water, with more than two thirds being either arid or semi arid. More than 41% of its population lack access to clean drinking water, posing high health risks. A major risk arises from consumption of water contaminated with heavy metals resulting to its bioaccumulation in the body. Conventional technologies used in the removal of heavy metals from wastewater include reverse osmosis, ultra filtration and electro dialysis. Since these methods are expensive; ion exchange is considered a better inexpensive alternative technique though not preferred due to large production of sludge involved. This has necessitated research on other cost effective and more efficient water treatment methods. Great attention has been given to alternative technologies such as biosorption for the removal of heavy metals from contaminated water. Biosorption employs the use of naturally occurring waste materials to sequester heavy metals from wastewater, encouraging water recycling and reuse. The present works aims at synthesizing alumino-phosphates materials using bone waste and its ash as the source of phosphate and then dete~ine their efficiencies and capacities in the removal of turbidity, colour, Cd2+ and Pb2+ ions from contaminated water. Alumino-phosphate adsorbents will be synthesized by using hydrothermal process. Batch experiments will be carried out to determine the effect of metal ion concentration, initial pH, ...
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