الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
In this study, nanostructure mesoporous titania (TiO2) was prepared using method titanium tetrachloride as precursor. While nitrogen doped titania (N-TiO2) was prepared using titanium tetraisopropoxide as precursor. The prepared photocatalysts were characterized by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), and Raman spectroscopy. Also, surface area and particle size were analyzed using BET equation. Also, the photocatalytic degradation of olive mill wastewater (OMW) and decolorization of Remazole Red (F3B) dye was studied over TiO2 and simonkolleite-TiO2 composite. The influence of catalyst dose and pH value of wastewater on the degradation of OMW and dye was investigated over TiO2 and simonkolleite-TiO2 composite. It was observed that the maximum amount of evolved hydrogen at TiO2dose of 2 g/L for TiO2 and 1.5 g/L for simonkolleite-TiO2 composite and solution pH value of 3 from OMW. On the other hand, chemical oxygen demand (COD) reduced by 82 % and 95 % over TiO2 and simonkolleite-TiO2 composite, respectively. The maximum amount of photocatalytic produced hydrogen from dye was 2.1 mmol and 3.3 mmol within 240 min using TiO2 and simonkolleite-TiO2composite, respectively. The specific production rate of hydrogen from photocatalytic conversion of dye was calculated. Improvement of apparent quantum yield after 4 h was achieved upon addition of simonkolleite to TiO2. This high apparent quantum yield proves that the system proposed in this study could be a hopeful approach toward using sunlight energy as outlook energy source. Based on obtained results, a new process for H2 production from wastewater can be achieved by coupling degradation of organic pollutants with photocatalytic H2 production. The process also provides a method for degradation of organic pollutants with simultaneous H2 production. Three-layer backpropagation neural network (3-18-2) was used for modeling of activity of n-TiO2 photocatalyst for photocatalytic hydrogen production with simultaneous dye removal degradation. The backpropagation neural network was configured to be three-layer ANN with tangent sigmoid transfer function (tansig) at hidden layer with 18 neurons for obtaining the smallest mean square error (MSE). The relationship between predicted results and the experimental results showed high correlation coefficient of 0.989 and MSE of 0.000376. The sensitivity analysis confirmed that the studied variables have strong effect on the process performance. Three-layer ANN could be used successfully for modeling of photocatalytic hydrogen production with simultaneous dye removal degradation. The cytotoxicity of Remazole Red dye and of BPA was investigated using human hepatocellular carcinoma cell line (HePG2) using modified neutral red uptake (NR) assay and Bradford assay. The effect of pollutants on the HePG2 cells morphology was investigated at different concentrations. The results showed that there are noticeable changes in the regular shape and size of the cells after incubation with higher concentration than 50 mg/L of F3B dye, wheresignificantcell monolayer disruption, cell shrinkage and presence of filamentous-shaped cells occurred. Lower concentration of Remazole Red dye has a slight effect on cell viability. The IC10 values showed the lowest toxicity and the IC50 values show the toxic values. It was noted that concentrations of dye lower than 50 mg/L in solution lead to only 7% decreasing in protein content after 48 h of exposure. Meanwhile up on exposure of HePG2 cells to dye concentrations of 50 and 100 mg/L, the protein content decreased by 20.4 % and 24.6 %, respectively relating to control samples. However, after exposure to dye concentrations of 200 and 250 mg/L for 48 h, protein content in HePG2 cells was decreased by 48 % and 56.4 %, respectively. The results showed that BPA had a deteriorating effect on cell viability after 48 h of exposure and significant inhibitory for cell proliferation after exposure for 48 h even upon exposure to any BPA concentration. The recorded IC50 and IC20 values for BPA were 30.34 and 8.42 mg/L, respectively. BPA has adverse effect on protein content of HepG2 cells which decreased by 97 % and 98 % after exposure to 25 mg/L and 50 mg/L of BPA, respectively. On the other hand, total protein content in HePG2 cells was completely disappeared up on exposure to 200 mg/L of BPA. The obtained results showed that the response of protein content in HePG2 cells was concentration-dependent. Bradford assay is more sensitive for toxicity than NR assay.