Abstract

Acacia nilotica was modified using eleven different treatments using ethanol, 0.1mol NaOH,0.1mol HCl and 10% glutarldehyde, it was reacted differently for 12hours on a magnetic stirrer then filtered and washed with distilled water till neutral pH. Preliminary studies was carried out, where 0.5g of biomass was reacted with 10ppm of Cadmium and Lead at pH 6 and stirred for 1hour then filtered, AAS was used for the determination of residual metal concentration to select the best treatment for batch sorption studies. Treatment 11 was selected as the best with 98% and 94% for Cadmium and Lead. Batch sorption studies were carried out to study the effects of pH, dosage, initial metal concentration and the effects of time on sorption capacity. The optimum sorption condition was found at pH 3, with 1g biomass dosage of Cadmium and Lead at 30mins equilibrium time. Characterization was also carried on the biomass using SEM-EDX, TGA and FTIR respectively. Acacia nilotica biomass showed a flaky rough surface with elongated thread like structures which contains carbon and oxygen, the amorphous nature of sorbent with the presence of Amine, Amide, Carboxyl and hydroxyl functional groups were present on the biomass. Thermal stability and decomposition of the biomass was also studied as a function of temperature. There was decrease in mass of the biomass in 4 steps which is the loss of volatile substances and moisture contents from 50 0 c to 150 0 c