Thesis (M.Sc.)--Chulalongkorn University, 2008

Aniline degradation was investigated using a cylindrical reactor with IrO₂/RuO₂ coated titanium metal anodes and stainless steel cathodes. A systematic experimental design was used as an initial screening process to determine the significant parameter (Fe²⁺, H₂O₂, pH and current) on aniline and COD removals. Results show that Fe²⁺, H₂O₂ and pH were the main factors affecting on the process performance. The Box-Behnken design was used to specify the optimum conditions from 16 experimental data. The optimized conditions for aniline and COD removals were 1.79 mM, 72 mM and 2 for Fe²⁺, H₂O₂, and pH, respectively. Under these conditions, aniline and COD removals were estimated to be 100 and 57.12%, respectively. The experiment performed under these optimum conditions provided the data which agreed very well with these estimations. In addition, the stepwise or continuous addition of H₂O₂ was more effective than the addition of H₂O₂ in a single step. Furthermore, the delay in electrical current supply for electro-Fenton process provides a possibility in reducing power consumption while maintaining the system performance.