The objective of this work is to determine the reflection elements, allowing the understanding of the phosphorus fixation mechanisms. The samples were taken from Oued Boufekrane in the Meknes region (Northwest of Morocco). In fact, the sediment characterization was examined by the Brunauer–Emmett–Teller (BET) specific surface area and Fourier-transform infrared (FTIR) spectroscopy measurements. A series of experiments were then carried out to study the impact of some parameters on the adsorption capacity. Indeed, the effect of contact time, sediment mass, pH, initial concentration of potassium dihydrogen phosphate KH2PO4, and the temperature has been studied. The characterization of sediment by FTIR spectroscopy shows the existence of carbonates, iron hydroxides, and organic matter. The results obtained showed that the retention of phosphorus on the sediments studied is maximal at pH = 12 and increases with the temperature and the mass of sediments. Phosphorus adsorption kinetics of phosphorus on sediments studied follows the pseudo-second-order model, and the activation energy value (48.51 kJ/mol) indicates the predominance of chemical nature of adsorption (>40 kJ/mol). The experimental data of the adsorption isotherms are well interpreted by the Freundlich model. The values of the thermodynamic parameters ΔG°, ΔH°, and ΔS° indicate that the adsorption reaction is endothermic and occurs spontaneously on the surface of the sediments studied.

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Due to its physical properties and its ease of manufacture, paper is widely used in various engineering applications such as electrical insulation materials for components in high voltage technology. In this study, paper loaded with ferroelectric nanoparticles (BaTiO3and SrTiO3) was made with fibers obtained from plants growing on the Moroccan soil [Halfa (Stipa tenacissima), Agave (Agave americana), Pennisetum (Pennisetum alopecuroides), Typha (Typha latifolia), and Junc (Juncus effusus)] and two commercial pulps (bleached softwood Kraft and newsprint grade thermomechanical pulps). A retention aid, cation polyacrylamide (Percol 292), was necessary to retain ferroelectric particles in the fibrous network and improve the dispersion of strontium titanate particles. The different pulp and handsheets used were characterized according to standard methods (Pulp and Paper Technical Association of Canada, PAPTAC). It is well known that annual and perennial plants contain high percentages of fines (length < 0.2 mm) and short fibers. The results show that there is a strong interdependence between the dielectric properties of the loaded paper and surface finish, porosity, dispersion level of ceramic particles, fines content, shape, conformability, and sheet formation. The single dielectric relaxation detected towards low frequencies is attributed to hydroxyl groups present on fiber surfaces, in ceramic particles and adsorbed water.