ABSTRACT:In this work, the decolorization of Methyl Orange was conducted using catalysts prepared by impregnation of copper on natural clay in the presence of H 2 O 2 . The catalysts Cu-clay, prepared from the concentrated metal precursor of (impregnation ratio, W(Cu(NO 3 ) 2 )/W(clay) = 1,5%-7,5%) were characterized by several methods such as X-ray diffraction (XRD), electronic scan microscopy (SEM), x-ray fluorescence (FX), and Brunauer-EmmettTeller (BET). Important factors affecting catalyst activity and methyl orange removal efficiencies were studied: the effects of temperature, oxidant concentration, and catalyst dosage. The results showed, a very significant activation of hydrogen peroxide by the catalyst, the Methyl Orange depletion percentage reaching 94 % after 2 h, and very stability of the catalyst. It was also observed that the best catalyst, at a reaction temperature of 25°C. 2,5ml of H 2 O 2 and 4.0 g/L of 5% Cu-clay, 94% decolorization was achieved within 120 min treatment. Although the Cu show high activity, their stability and reusability still need improvement.

The classic preparation way of the electronic ceramics is the solid reaction. This method begins to yield the place to chemical preparation techniques that give powders of high purity and an uniform granulation. Barium Titanate ceramics are interesting to study because of their simple structures and the modulation of their properties when we dope them by transition elements. In fact, the substitution of the ion Ti 4+ by Zr 4+ modifies appreciably the dielectric and structural properties of BaTiO 3 . In this work, we present a new process of the preparation of BaTiO 3 (BTO) and BaTi 0.8 Zr 0.2 O 3 (BZT) (pure and doped with Cu and Sb) by the hydrothermal way. This process permits us to obtain ferroelectric ceramics from cheaper precursory at relatively low temperatures. The analysis of the samples by scanning electron microscopy shows that the obtained powders are spherical grains form perfectly homogeneous (the size of the grains is about 0.2m). The cell parameters have been determined from X-rays spectrum. The evolution of theses parameters related to the synthesis conditions and the thermal processing will be discussed. s6.m20.p6Cyclodextrin inclusion complexes of the local anaesthetics butamben, procaine and disoprofol: PXRD, single crystal X-ray diffraction and thermal analysis.Powder X-ray diffraction techniques were used to characterize inclusion complexes formed between the local anaesthetics butamben (4-aminobenzoic acid butyl ester), procaine [4-aminobenzoic acid-2-(diethylamino)-ethyl ester], disoprofol (2,6-diisopropylphenol) and the native cyclodextrins (CDs) b-CD and g-CD. Single crystals of a 1:1 inclusion complex between butamben and permethylated b-CD (TRIMEB) were isolated and the structure determined. X-ray analysis revealed that the guest is included with the ester moiety fully encapsulated in the TRIMEB cavity. However, a major part of the phenylamine residue protrudes from the host primary side, entering the secondary side of a translated TRIMEB molecule to which it hydrogen bonds, both directly [-NH A ×××O(host)] and indirectly [-NH B ×××O(water)×××O(host)]. This unusual mode of guest inclusion is associated with a novel channel-like complex packing arrangement in the monoclinic space group P2 1 . The included guest molecule adopts a different conformation from that found in the crystal of the uncomplexed drug.