Optimization of Photocatalytic Degradation of Phenol Using Simple Photocatalytic Reactor

Innocent Udom, Philip D. Myers, Manoj K. Ram, A. F. Hepp, Edikan Archibong, Elias K. Stefanakos, D. Yogi Goswami

Clean Energy Research Center, College of Engineering, University of South Florida, Tampa, USA.
Department of Chemical and Biomedical Engineering, University of South Florida, Tampa, USA.
NASA Glenn Research Center, Research and Technology Directorate, Cleveland, USA.

DOI: 10.4236/ajac.2014.511083                

Abstract

The phenol photocatalytic degradation was investigated using heterogeneous catalyst Ag-doped ZnO nanowires under UV irradiation. Ag-ZnO nanowires were immobilized on borosilicate glass via a simple hydrothermal technique. Preliminary photodegradation studies were performed with Ag-ZnO nanowires at various concentrations of phenol (10 - 60 mg/L) at undiluted pH. After determination of the optimal initial concentration (30 mg/L), additional parameters including pH and light intensity were investigated to optimize photodegradation of phenol for large-scale application. The experimental results illustrate that the kinetics of degradation of phenol are pseudo-first order. Based on the relationship, experimental model and empirical correlation were generated and compared for validity. The experimental data were found to fit a cubic model (linear in UV irradiation intensity, I, and cubic in pH), over ranges of 10 - 60 W (UV lamp power) and 2.7 - 11.0 (pH) with a coefficient of determination (R²) of 0.9934. This model, of the form K(I, pH) = c₀₀ + c₁₀I + c₀₁pH + c₁₁IpH + c₀₂pH² + c₁₂IpH² + c₀₃pH³ was found to yield a better fit than simpler (quadratic) or more complex (quartic) polynomial-based models considered. The model parameters c_ij and corresponding 95% confidence intervals were obtained.

Keywords

Ag-ZnO Nanowires, Photocatalyst, Photodegradation, Phenol, Model

Conflicts of Interest

The authors declare no conflicts of interest.

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