Experimental and Kinetic Study of Phenol Oxidation Using Ni-oxide Catalysts

The current study focuses on the investigation of Nickel Oxide in advanced oxidation process of phenol. The removal of phenol from aqueous phase continues to be an important environmental issue. In this work, the oxidation of phenol in aqueous solutions in a batch reactor using nickel oxide was studied. The efficiency of the system was evaluated with respect to reaction time, pH, feed concentration of reactants, catalyst load. The concentrations of phenol after reaction were determined by UV visible. The results showed that the optimum conditions ( 100% conversion at 90 min) were obtained at a neutral pH, with 0.5 g of Nickel Oxide and 18oC. However, decreasing of efficiency was observed for pH in the range of 2–12. The results showed that increasing temperature from 18oC to 50oC lead to decrease the conversion from 80% to 62%. Analytical profiles on phenol transformation were consistent with the best line fit of the Eley-Rideal Mechanism. Moreover, the degradation rate constants k and Ke were found 1.1*10-3 (cm3.liter/gcata) and 4.9889 respectively with R2=0.99522. Finally, the results of mineralization studies indicated that dechlorination was better accomplished but more time was required to completely mineralize phenol into water and carbon dioxide.