Browsing by Author "Tewodros, Geremew"

Now showing 1 - 1 of 1
  • No Thumbnail Available
    Item
    Catalytic Oxidation of Phenol in Aqueous Solution using Fe - Sulfonated Carbon Catalyst
    (Addis Ababa University, 2018-07) Tewodros, Geremew; Beteley, Tekola (PhD)
    The main objective of this research was to mineralize phenol in aqueous solution using Fe – Sulfonated carbon catalyst. Two fairly different catalysts (Fe/AC and Fe/AC − SO iii 3 H) in terms of impregnation (FeSO 4 . 7H 2 O for 8hr) and sulfonation (with high concentrated sulfuric acid 98 % for 15hr under N 2 ) were successfully synthesized and compared. The synthesized catalysts were characterized using: pH of zero point of charge, bulk density, total acid density, FT-IR spectroscopy, iron stability, TGA, reusability and performance comparison test with D-optimal experimental design through varying pH of the solution. The result shows that Fe/AC − SO 3 H with maximum acid density, higher iron stability with high reusable capacity. In addition to this, the performance comparison test ensured a maximum phenol removal efficiency and TOC reduction of 8 % and 21.6 % respectively, for Fe/AC − SO 3 H catalyst higher than former catalyst. Thus, from synthesized catalysts Fe/AC − SO 3 H was selected based on the above characterization and further performance analysis was taken place to search for optimal condition. The selected Fe/AC − SO 3 H catalyst was studied for its activity to catalyze mineralization of phenolic aqueous solution using heterogeneous fenton process. Design-Expert 7.0.0 three-levelthree-factor with full factorial was applied for experimental design and statistical analysis using a respective process variables; reaction temperature 30, 60 and 90℃, hydrogen peroxide concentration of 1000, 3500 and 6000 mg/L and 60, 150 and 240 min of reaction time. From the analysis of experimental results the interaction effects were studied and the optimal mineralization reaction process conditions, which will maximize the percentage of TOC reduction, were found to be 57.12 ℃ reaction temperature, 2869.72 mg/L hydrogen peroxide concentration and 119.38 min reaction time which gave 97.94% of TOC reduction. The experimental results were fitted well with the derived response model with the R 2 statistic measure, it is evident that the fit successfully accounted for greater proportion of variance as all the models explained ≈ 98.08 %, 99.8 % and 89.85 % for temperature 30 ℃, 60 ℃and 90 ℃ respectively, of the total variation in the data. In average only 4.09 % of the total variations were not explained by FKM and GLKM. However, as GLKM contains more coefficients than the FKM, R-square statistic, a generally accepted best indicator of the fit quality in the comparison of models with those that are nested, is used.