Nanotechnology is one of the fastest growing sectors of the high-tech economy, with more products than ever before are using nanoparticles for personal, commercial, medical, and military application. The term nanoparticle is generally used to refer to a small particle with dimensions less than 100 nanometers (nm). Its small size and large surface area per unit mass impart characteristics that can be useful in hazardous waste site remediation and contaminant reduction such as Pb, Cr, Cd, etc. The main focus of this study was on the synthesis of zerovalent iron nanoparticles using coffee bean extract as reducing agent. The reducing potentials of Wembera (W) and Sidama (S) coffee extracts were studied by determining the total phenolic content (TPC) at different extraction times. The mean TPC of Sidama coffee was 47.7, 57.6 and 110.2 mg gallic acid equivalent (GAE)/g for extraction times of 10, 15 and 20 min respectively. The mean TPC of Wembera coffee was 36.7, 60.8 and 52.5 mg GAE/g for extraction times of 10, 15 and 20 min respectively. The result showed that the TPC of Sidama coffee was high for longer extraction time than Wembera coffee. The nano zerovalent iron (nZVI) was synthesized using the two coffee varieties with highest TPC. The synthesized nZVI was characterized by TEM, FTIR and XRD. The size of W-nZVI and S-nZVI analyzed by TEM were 6.07 ± 0.16 nm and 1.43 ± 0.53 nm, respectively. The batch experiment was conducted for adsorption of chromium (VI) at different temperature, pH and the initial concentration of Cr (VI). The highest percent of hexavalent chromium adsorbed on to W-nZVI and S-nZVI was 90 and 93.96, respectively. This removal efficiency was achieved at pH of 3, initial Cr(VI) concentration of 10 mg/L and temperature of 30 ºc. In this thesis, both thermodynamic and kinetic studies were conducted. The maximum adsorption capacity of W-nZVI and S-nZVI was calculated to be 35 and 38 mg/g, respectively.