Hundessa, Dessalegn (PhD)Nahom, Kahsay2020-03-082023-11-102020-03-082023-11-102019http://etd.aau.edu.et/handle/12345678/21001Arsenic is the most hazardous element in the chemical world and its presence in drinking water can cause disaster. Conventional method of preparation of nano zero valent iron using physical and chemical methods normally employ toxic chemicals as reducing agents, organic solvents, or non-biodegradable stabilizing agents, and are therefore potentially dangerous to the environment and biological systems. Experiments were conducted in a batch system and the effects of pH, contact time, and the initial concentrations of Arsenic (III) and nanoscale zero valent iron doses were investigated. The nature and morphology of synthesized adsorbent were characterized by X-ray diffraction and Fourier transform infrared spectroscopy. The experimental results revealed that the removal efficiency of Arsenic (III) was increased with decreasing pH of the solution but decreased with gradual increasing of initial concentration and dosage. The removal rate of Arsenic (III) was 97.4 % at a dosage of 1.0 g, pH 2 and with 15g/L initial As(III) concentration. The experimental data was found to be well described by Langmuir model. The maximum loading capacity as estimated by Langmuir model was 116.27 mg/g. Also, the adsorption trend followed the pseudo-second order kinetics model and equilibrium was achieved in two hours. Overall, the results obtained indicate that CMC-Stabilized nZVI could be effectively used for removal of Arsenic (III) from waste water.en-USArsenicnano zero valent ironAdsorptionThesis