A RESEARCH PROJECT SUBMITTED TO THE DEPARTMENT OF BIOLOGICAL AND PHYSICAL SCIENCES IN THE SCHOOL OF PURE AND APPLIED SCIENCES IN PARTIAL FULFILMENT OF REQUIREMENTS FOR THE AWARD OF THE DEGREE OF BACHELOR OF SCIENCE OF KARATINA UNIVERSITY

Abstract

With Kenya's industrialization comes an increase in the pollution of water bodies by heavy metals. Wastewater treatment techniques currently used are pricy. Membrane filtration, chemical precipitation, ion exchange, solvent extraction, and flotation are a few of them. There are emerging new and less expensive technologies that use activated carbon and locally accessible biomass. In order to remove lead ions from wastewater, this study set out to prepare activated carbon and to determine the optimal temperature, PH, adsorbent mass, and phosphoric acid concentrations for carbonization and activation using avocado (Persea americana) seed wastes. Activated carbon was prepared by made by soaking fifty grams of (Persea americana) seeds powder in 50 % phosphoric acid for 24 hours, which was then oven dried for 48 hours at 105°C. Dried sample was heated using a heating mantle at 300°C. After cooling, the sample was washed with 0.1 HCl to remove ash content, and then washed with 0.1M NaOH to neutralize pH. Optimizing parameters such as temperature, PH, adsorbent mass and phosphoric acid concentration were studied. Adsorption of lead ions increased with increase in concentration up to an optimum 50% concentration. Adsorption of lead ions increased with increase in PH up to an optimum PH of 4. Adsorption of lead ions increased with increase in adsorbent mass up to an optimum adsorbent mass of 1.2g. Adsorption of lead ions increased with increase in temperature up to an optimum temperature of 600℃. Thus, optimizing activation conditions would produce a better activated carbon from avocado seeds that would be used to remove heavy metal ions from water. It also eliminates the problem of agricultural wastes accumulating in our environment