Study of physico-chemical characteristics of nickel insertion in phosphogypsum

The main purpose of this work is study the influence of the insertion metal ions Ni (II) in the phosphogypsum produced by sulfuric acid attack of tricalcium phosphate. Indeed, the maximum content of heavy metals calcium sulfate that can absorb was determined. The added ions are (NiCl2, 6H2O) with mass concentrations ranging from 5% to 50%. The samples prepared were characterized by various methods, such as X-ray diffraction (XRD), infrared spectroscopy and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The results of this study showed that the limit of insertion of metal cations in calcium sulfate is limited to 30% for nickel

Study of the photodegradation of tribenuron-methyl in aqueous solution of two Moroccan soils

Photodegradation of Tribenuron-methyl [methyl 2-(((((4-methoxy-6-methyl-1,3,5-triazin-2- yl)methylamino)carbonyl)amino)sulfonyl)benzoate] was carried out in aqueous solution under UV light. The research of the structures of the photoproducts highlighted by follow-up CLHP was carried out by coupling CLHP/SM. The results of this study allowed concluding that the transformation of the tribenuron-methyl depends on the pH of the medium and the light of irradiation. With this intention, the study of the retention, the mineralization of the tribenuron-methyl in two Moroccan soils of the area of Gharb (Northwest of Morocco) called Tirs and Dehs was carried out using the molecule labelled on carbon ureic and in controlled conditions. The adsorption and desorption of the tribenuron-methyl by the two grounds were carried out by the method of Batch balancing. The adsorption of the active matter follows a nonlinear isotherm. The ground Dehs has a more important affinity for the molecule the tribenuron-methyl than the ground Tirs. The desorption of the tribenuron-methyl is more important starting from the ground Dehs. The mineralization of the molecule by biological way is more important starting from the ground Tirs. The contribution of nitrogen seems to inhibit the process of mineralization starting from this ground