الفهرس 
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Abstract
The efficiency of conventional biological technologies is limited for treatment of industrial wastewater containing bio-recalcitrant pollutants. In this PhD dissertation, solar photocatalysis and solar photo-Fenton processes were investigated for treatment of pesticides, phenolic, and pharmaceutical wastewater. The effect of initial pH, loading of Fenton reagents, and TiO2 on the removal efficiency of pesticides and COD was assessed. The removal of COD was 90.7 % and 79.6% by photo-Fenton and TiO2 photocatalysis respectively. Moreover, photo-Fenton process was more efficient for degradation of pesticides fractions. However, addition of H2O2 to photocatalysis process (UV/H2O2/TiO2) improved the removal of COD (84%) and degradation of pesticides. The kinetic study showed that degradation of pesticides by both of photo-Fenton and photocatalysis followed pseudo first order pattern. The estimated costs for photocatalysis and photo-Fenton processes were 8.69 and 5.20 €/m3 respectively. The effluent quality was not complying for discharge into sewerage network. Therefore, post treatment by powdered activated carbon (PAC) was assessed. Activated carbon is uneconomic if it used for high contaminated water because high amount of activated carbon is needed, however in case of low concentrations of contaminant like post treatment the needed amount of carbon is low. The combined processes provided almost complete removal of pesticides i.e. 97% for lambda-cyhalothrin, 91% for chlorpyrifos, and 100% for diazinon. TiO2 was immobilized on activated carbon (TiO2/AC) by temperature impregnation method for treatment of phenolic and pharmaceutical wastewater. characterization of TiO2/AC by Brunauer-Emmett-Teller (BET) analysis, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope (SEM) revealed successful immobilization of TiO2 on activated carbon. 80% of phenol was degraded by TiO2 after 150 minutes of irradiation. This was not the case for TiO2/AC as phenol was completely degraded after 120 minutes of irradiation. Moreover, in TiO2/AC photocatalysis, the presence of aromatic intermediates (Catechol, hydroquinone, and benzoquinone) was relatively low as compared to TiO2 photocatalysis. Similar trends were observed for degradation of pharmaceuticals where amoxicillin and ampicillin were completely eliminated by TiO2/ AC. On the other hand, only 89% of amoxicillin and 83% of ampicillin were removed by naked TiO2. Likely, TiO2/AC achieved higher removal efficiency of diclofenac (85%) and paracetamol (70%) as compared to naked TiO2. Moreover the costs estimation study showed that TiO2/AC is more economic. Complete degradation of phenol with initial concentration of 100 mg/L using photo-Fenton process after 45 minutes of irradiation. However, increasing the initial concentration up to 500 mg/L inhibited the degradation efficiency. Similarly, pharmaceuticals (Amoxicillin, ampicillin, paracetamol, and diclofenac) were completely removed after 90, 120, 60, and 120 minutes of irradiation respectively. The optimum removal of pharmaceuticals was attained at (pH=3.0). H2O2 dosage of 1.5 g/L, and FeSO4.7H2O dosage of 0.5 g/L.
A novel catalyst (Ru/WO3/ZrO2) was investigated for removal of carbofuran (pesticide) and ampicillin (pharmaceutical). The degradation of carbofuran and ampicillin after 180 minutes of irradiation was 100% and 97% respectively. The durability of catalyst was assessed by reusing the suspended catalyst and showed 92% of its initial efficiency.