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Many emerging contaminants pass through conventional wastewater treatment plants, contaminating surface and drinking water. The implementation of advanced oxidation processes in existing plants for emerging contaminant remediation is one of the challenges for the enhancement of water quality in the industrialised countries. This paper reports on the production of a TiO 2 nano-layer on quartz wool in a relevant amount, its characterisation by X-ray diffraction and scanning electron microscopy, and its use as a photocatalyst under ultraviolet radiation for the simultaneous mineralisation of five emerging organic contaminants (benzophenone-3, benzophenone-4, carbamazepine, diclofenac, and triton X-100) dissolved in deionised water and tap water. This treatment was compared with direct ultraviolet photolysis and with photocatalytic degradation on commercial TiO 2 micropearls. The disappearance of every pollutant was measured by high performance liquid chromatography and mineralisation was assessed by the determination of total organic carbon. After 4 hours of treatment with the TiO 2 nano-coated quartz wool, the mineralisation exceeds 90% in deionised water and is about 70% in tap water. This catalyst was reused for seven cycles without significant efficiency loss.

analyser. Oxidation of the Al powder was carried out under compressed air, with a flow rate of 100 ml min -1 , at isothermal temperatures of 400, 450, 500 and 550°C for up to 60 min. Gas release from as-received and TiH 2 powders heat treated at isothermal temperatures of 400, 450, 500 and 550°C for 60 min, was characterised by heating under argon at a rate of 10 Jmin -1 . In all cases, approximately 20 mg of powder was used and the results were normalised for equal mass. Oxygen analysis of as-received and heat treated Al powders and compacts was performed using a LECO analysing system which enables the oxygen content (in wt.%) to be measured to 3 decimal places.Foaming behaviour: Al-TiH 2 precursors were foamed in a mechanical expandometer in which foam expansion was monitored in-situ versus time. The expandometer is constructed from a moving piston, which rests on top of a precursor, which expands in a tubular mould, and is connected to a counterweight by a thin wire. [5] The 22 mm diameter stainless steel mould, foamable precursor and piston were placed in a vertical tube furnace which was pre-heated to 800°C. The measured precursor temperature reached a maximum of 780°C after foaming for roughly 450 s. Foam expansion was measured and recorded to a computer via a linear variable displacement transducer attached to the counterweight. Some precursors were also foamed in a cylindrical stainless steel mould placed in a furnace pre-heated at 800°C. Foaming times of 330, 360 and 480 s were adopted in order to capture the macrostructures during the initial, maximum and collapse phases of the expansion process.Foam samples were sectioned longitudinally, along the mid-plane, using electro-discharge machining to minimise damage to the cell wall structure. Contrast in the foam structure was enhanced by spraying matt black paint over the surface of the samples and then removing it from the sectioned cell walls by light grinding on SiC papers. The painted foams were scanned using a HP Scanjet 6100C at resolution of 100 dpi. For microstructural investigation, the samples were mounted in cold-setting epoxy resin with an electrical contact at the back, ground and polished, finishing with a 1 lm diamond wheel. To reveal grain contrast, the samples were anodised in a solution of 2 % HBF 4 in water, for 45 sec. at 30 V, and viewed in an optical microscope under cross-polarised light.Wet chemical routes for the synthesis of lead zirconate titanate electroceramics have been extensively investigated in order to achieve more reactive powders with a low stoichiometric fluctuation and nanometer dimension of primary particles. Among these, coprecipitation of hydroxides, oxalates, peroxo-hydroxides, and mixture of hydroxides and oxalates has practical advantages (low cost starting materials, good chemical yields) but is limited by preferential precipitate formation and incomplete precipitation. [1][2][3][4] The main consequence of the low control of the precipitation kinetics is the formation of intermediate phases (PbTiO 3 ) during th...