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The sequential extraction procedure proposed by the Standard, Measurements and Testing program "SM&T" of the European Union has been applied to evaluate the amounts of Cr, Cu, Mn, Ni, Pb and Zn, extracted at each stage and indirectly their mobility and bioavailability in soil and sediment samples from a polluted area. Analysis of the extracts was carried out by flame atomic absorption spectrometry (FAAS). No significant matrix interferences were found except for Cr in the acetic acid and hydroxylammonium chloride extracts, which required determination by the standard additions method. Both of soils and sediments studied show similar partitioning of Mn, Ni, Cu and Cr. Mn and Ni can be considered to have significant component bound to the acido-soluble fraction, whereas, Cr and Cu occur largely in the organic and residual phases. The partitioning of Pb and Zn was different between soil and sediment. In terms of mobility and bioavailability, in soils, Ni and Mn can be regarded as moderately available followed by a lower availability of Pb while Cu, Zn and Cr have a very limited availability. In sediments, a higher availability (short-medium term) of Mn and Zn was presumed followed by a lower availability of Ni and Pb, whereas, Cu and Cr, occurring largely in the organic and residual phases, were of very limited availability.

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This study aimed to evaluate the sorption capability of an inexpensive and easily available Moroccan clay, called locally Ghassoul, to remove Rhodamine B (Rh-B) from aqueous solution. Experimental results showed that the equilibrium sorption data fitted well with the Langmuir isotherm and the monolayer sorption capacity was estimated as 448 mg g -1 at 298K. Kinetic analyses showed that the sorption rate was more accurately represented by a pseudo second-order model. The intra-particle diffusion was involved in the overall rate of the sorption process but it was not the only ratecontrolling step. The calculated thermodynamics parameters showed the spontaneous and the endothermic nature of the sorption process. The activation energy found to be 5.36 kJ mol -1 could indicate a physical sorption process. The obtained results confirmed the applicability of this clay as an efficient and economical adsorbent for cationic dyes from contaminated water.