عامر موسى جودة الشمري

In this research, activated carbon (coconut husk waste) is prepared using sulfuric acid activation from coconut husk waste which is a cheap material that shows agreed scavenging actions by adsorption for eliminating the toxic textile dyes (methylene blue MB, crystal violet CV, as well as Brilliant Blue BB) from the aqueous solutions. In a shaker water bath, different physio-chemical factors like contact time, adsorbent dose, pH, temperature of the dye solution and initial concentration of the dye have been measured and the adsorption time is 120 minutes. The results show that adsorption of MB, CV is favorable at a high pH value, but at acidic pH, the brilliant blue BB dye is favorable. The activated carbon thermodynamic analysis is conducted using three dyes: The Gibbs free energy, entropy and also enthalpy. According to the results, the adsorption is a Physical (endothermic). It is also found that the activated carbon is regulated by the equations of Freundlich and Temkin. Finally, field emission scanning electron microscopy (FE-SEM) and Fourier-transform infrared spectroscopy (FT-IR) have been used to show adsorption.

Nanocomposite (MgO/α-Fe2O3), MgO and α-Fe2O3 have been prepared using a simple hydrothermal route at temperature of 180°C for 4h. The products were inspected by using Field Emission Scanning, Electron Microscopy, Atomic Force Microscopy, UV-Visible Spectroscopy, and X-Ray Diffraction. Inclusive characterization of the structures (MgO/α-Fe2O3), MgO and α-Fe2O3 with crystal structures. The photocatalytic activity of the nano composite, (MgO/α-Fe2O3) was examined over methylene blue (MB) dye under UV-Visible light irradiation. The photocatalytic activity was evaluated with several parameters involving difference of pH, catalyst dose, initial dye concentration and temperature. The degradation efficiency of dye on nanocomposite catalyst was detected to be 93% and 95% within 6 min of irradiation ultraviolet and visible light respectively designated a decrease in the absorbance intensity and concentration of the dye. These results show that MgO/α-Fe2O3 is appropriate for treatment of wastewater.

In order to obtain inexpensive and effective application of catalyst for photodegradation, Cu2O powder was prepared by the simple and inexpensive electrodeposition method using surfactants such as glycerin (GLY), polyvinyl alcohol (PVA), poly(N-vinylpyrrolidone) (PVP) that helped the growth and nucleation of suspended particles. These particles were distinguished by atomic force microscopy (AFM), X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM). Diameter size of these obtained particles was found to reach to about 40 nm. In order to demonstrate the photodegradation efficiency of the copper oxide in the removal of organic malachite green oxalate (MG) dye, the catalyst was used both in calcination at 300 °C and without calcination. Parameters such as the amount of catalyst, the concentration of dye, the pH of dye sol, and the temperature were calculated. Pseudo first order reactions according to Langmuir-Hinshelwood kinetics could be obtained from the result of photocatalytic reactions. Parameters such as energy activation (Ea), enthalpy of activation (ΔH0 ), entropy of activation (ΔS0 ) and free energy of activation (ΔG0 ) were calculated. The activation energy was equal to 11.719 ± 1 and 11.083 ± 1 kJ/mol for MG dye in the presence of Cu2O nanoparticles in both two cases of calcination and without calcination respectively.

This study involves the photocatalytic degradation of Carmine dye, employing heterogeneous photocatalytic process. Photocatalytic activity of different catalysts such as zinc oxide (ZnO) , and Nano ZnO has been investigated. An attempt has been made to study the effect of process parameters through amount of catalysts, concentration of dye, pH of dye solution and temperature on photocatalytic degradation of dye solutions. The optimum catalyst dose was found to be( 0.75 g and 1) g\L for Nano ZnO, ZnO respectively. In the case of for Nano ZnO, ZnO , maximum rate of photoreaction of dye solutions was observed in acidic medium at pH 4 for ZnO whereas the degradation of dye reached maximum at pH 2 when using NanoZnO catalyst . The performance of photocatalytic system employing NanoZnO/UV light was observed to be better than ZnO/UV system. Photocatalytic degradation was found to increase with increasing temperature. Arrhenius plot shows that the activation energy is equal to 8.07 kJ mol−1 with ZnO and 1.2389kJ mol−1 with Nano ZnO catalyst.The results display that the action of dissimilar kinds of catalyst used in this work is of the sequence: Nano ZnO > ZnO