الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
In this study, the photo-degradation of ammonia and phenol onto four different new catalysts was studied “N-Doped ZnO Beads (NZB) ,N-Doped TiO2 Beads (NTB) , N doped ZnO-AC (N-ZnO/AC) and N-doped TiO2-AC (N-TiO2/AC) “ , were synthesized via a modified sol-gel technique .NZB, NTB , N-ZnO/AC and N-TiO2/AC were analyzed by BET surface area, N2 adsorption-desorption isotherms, X-ray Diffraction (XRD),Scanning electron microscope (SEM) , EDS , Fourier transform infrared (FTIR) measurements, X ray photoelectron spectroscopy analysis (XPS), Raman studies and Diffuse reflectance spectroscopy (DRS) studies. The use of the nitrogen doping method for photo-catalyst was performed in order that improve the band-gap and electrical characteristics of ZnO and TiO2 by developing acceptor defects. Four catalysts with the intrinsic donor defect of oxygen vacancy and the nitrogen-to-oxygen acceptor defect could be activated by a less energy UV consumption for efficient pollutant degradation. Degradation for ammonia and phenol from aqueous solution using four photo-catalysts within the existence of Hydrogen peroxide (H2O2) and UV irradiation is evaluated through semi-continuous photo-reactor. NZB achieved 98.28% and 95.75% degradation for both ammonia and phenol, respectively, after 2 hrs of UV irradiation at pH 6.5 and flow rate 0.25 L/min. NTB achieved 92.42% and 94.81% degradation for both ammonia and phenol respectively after 2 hrs of UV irradiation at pH 6.18 and flow rate 0.25 L/min. For N-ZnO/AC, ammonia degradation was 83.07% and phenol degradation was about 87.88 % at pH 6.7 and flow rate 8 L/min after 2 hrs of UV irradiation. For N-TiO2/AC, ammonia degradation reached 69.67% and phenol degradation was about 66.73 % at pH 6.7 and flow rate 8 L/min after 2 hrs of UV irradiation. RSM “Response surface methodology” was utilized for degradation of ammonia and phenol by using N-ZnO/AC catalyst. Regression analysis shows that the experimental data fits well with the second-order polynomial model, and (R2 ) value of 0.9872 for ammonia degradation model and 0.9901 for phenol degradation model. Also, the reusing ability and strength of four catalysts were investigated. The developed four types could be used as a new promising photo-catalyst for the degradation of ammonia and phenol from wastewater.