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Due to the high number of anti-inflammatory drugs (AIMDs) used by the public health sector in Iraq and distributed all over the country and due to their toxicity, there is a need for an environmental-friendly technique to degrade any wasted (AIMD) present in aquatic ecosystem. The degradation of diclofenac sodium (DCF), ibuprofen (IBN), and mefenamic acid (MFA) in synthetic hospital wastewater were investigated utilizing locally-made Cu-coated TiO2 nanoparticles in a solar-irradiated reactor. Different key variables were studied for their effects on process efficiency, such as loadings of catalyst (C CU-TiO2 = 100–500 mg/L), AIMDs (100 µg/L), pH (4–9), and hydrogen peroxide (CH2O2 = 200–800 mg/L). The results revealed that degradation percentages of 96.5, 94.2, and 82.3%, were obtained for DCF, IBN, and MFA, respectively, using our Cu-coated TiO2 catalyst within 65 min at pH = 9, while other parameters were C CU-TiO2 = 300 mg/L, and CH2O2 = 400 mg/L. The experimental results revealed coupling photocatalysis with solar irradiation as a clean energy source could be utilized for the degradation of toxic pollutants in surface water.

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This experimental study is aimed at investigating the effect of superficial gas velocity, liquid phase properties and gas distribution on gas holdup, bubble characteristics and drag coefficient in two-phase bubble column. Various liquids covering a sufficiently broad range of viscosity and surface tension values were employed, while the gas phase was atmospheric air. Aqueous glycerine solutions were used to simulate the behavior of coalescing viscous liquids whereas aqueous alcohol solutions were used to simulate the behavior of non-coalescing organic liquids. The experimental results obtained with two different types of gas distributor in the coalescence solutions and in non coalescence solutions were compared with data on standard air-water system. A computerized conductivity probe system and high speed digital camera were used for the systematic measurements of bubble size, velocity and gas hold-up. Correlations based on dimensionless groups were proposed for the prediction of gas holdup and drag coefficient in the homogeneous flow regime.

The present study was classi ed into two sections. In the rst, a kinetic analysis of the oxidation of phenol in aqueous solution over a supported (0.7% Pt)/Al 2 O 3 catalyst was investigated at atmospheric pressure in a batch operating system. The kinetic analysis proved that the reaction consists of two mechanisms, and that the initial rate and steady state activity regimes which exhibited rst order behavior with respect to phenol concentration. The reaction rates show an unusual dependence on catalyst loading which suggested a heterogeneous-homogenous free radical mechanism. Phenol removal can be increased by increasing the amount of oxygen gas but at higher ow rates of oxygen a retarding e ect of oxygen on phenol oxidation was observed. In the second section, a comparative study of the catalytical wet oxidation (CWO) of phenol in two di erent types of ow reactors (i.e., falling lm and back mixing reactors) was carried out and design parameters such as inlet temperatures, residence time of reactants and catalyst loading in the reactors were used to establish similarity reaction conditions in the two reactors. The study supports the following conclusions: The oxidation rate of phenol was low because of the solubility of oxygen under atmospheric conditions. At low ow rates of liquid reactant the falling lm reactor showed a better performance as a result of its lower resistance to mass and heat transfer while the result is completely di erent at higher liquid ow rates. Non-isothermal operation showed that water evaporation has a strong impact on phenol conversion and must be taken into account in scale up and adiabatic CWO reactor design. Neglecting evaporation can lead to erroneous calculation of the exit stream phenol conversion and temperature. The power law technique has been utilized to correlate the phenol conversion with the operating parameters in the two reactors.