The photochemistry of aqueous nitrate solutions excited in the high-energy (195-nm) mr* band of the ion is investigated using steady-state and flash-irradiation techniques. The formation of hydroxyl radicals is demonstrated by observing the absorption of characteristic transients formed by the reaction of O H (or 0-) with C082-, CNS-, and 02. T h e formation of pernitrite is also investigated and found t o be unaffected by [NO2-], [NOI-], [02], and [CH,CH20H]. The flash technique enables the determination of the dissociation constant of pernitrous acid, yielding pK, = 6.0 =t 0.3. A third photochemical path, the evolution of 02 and the stoichiometric formation of NOz-, is also investigated. T h e effect of various solutes on the yields of molecular oxygen is analyzed, The results appear to be inconsistent with a mechanism involving intermediate oxygen atoms.

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The efficiency of Al-Quds Waste Water Treatment Plant (WWTP), which includes sequential elements as activated sludge, ultrafiltration, activated carbon column and reverse osmosis, to remove spiked ibuprofen, a non steroid anti inflammatory drug (NSAID), was investigated. Kinetic studies in pure water and in the activated sludge indicated that the drug was stable during one month of observation. Besides, the overall performance of the integrated plant showed complete removal of ibuprofen from wastewater. Activated carbon column, which was the last element in the sequence before the reverse osmosis system, yielded 95.7% removal of ibuprofen. Batch adsorptions of the drug by using either activated charcoal or composite micelle-clay system were determined at 25°C and well described by Langmuir isotherms. Octadecyltrimethylammonium (ODTMA) bromide and montmorillonite were used to prepare the micelle-clay adsorbent, for which the adsorption kinetics are much faster than activated charcoal. Results suggest that integrating clay-micelle complex filters within the existing WWTP may be promising in improving removal efficiency of the NSAID.

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