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The Black Steel slag (Ss) and phosphogypsum (PG) are industrial wastes produced in Morocco. In order to reduce these two wastes and to evaluate their pozzolanic reactivity in the presence of water, they were incorporated into bentonite (B) mixed with lime (L). The studied mixtures (BLW, BL–PG–W and BL–PG–Ss–W) were analyzed by X-ray diffraction, Infrared spectroscopy, Raman spectroscopy and SEM/EDX analysis. Compressive strength tests were performed on hardened specimens. The results obtained show that the hydration kinetics of the B–L–W and B–L–PG–W mixtures are slow. The addition of PG to a bentonite––lime mixture induces the formation of new microstructures such as hydrated calcium silicate (C–S–H) and ettringite, which increases the compressive strength of the cementitious specimens. The addition of the Ss to a mixture composed of 8%PG and 8%L–B accelerates the kinetics of hydration and activates the pozzolanic reaction. The presence of C2S in the slag helps to increase the mechanical strength of the mixture B–L–PG–Ss. The compressive strength of the mixtures BL–W, BL–PG–W and BL–PG–Ss–W increases from 15 to 28 days of setting. After 28 days of setting, 8% of Sc added to the mixture 8% PG–8%L–B is responsible for an increase of the compressive strength to 0.6 MPa.

Remediation of contaminated water with organic dyes originated from variety of industrial processes deserves increased attention. Raw clay is an effective low-cost and eco-environmentally friendly adsorbent for the removal of methylene blue (MB) from solution. This study aims to determine kinetics and thermodynamics of MB adsorption onto raw kaolin clays (halloysite and kaolinite/illite) from northeast of Morocco. The apportion capacity of the two kaolin clays to adsorb the MB dye by varying temperature and pH conditions was studied. The thermodynamic parameters show that the sorption of MB is spontaneous and endothermic for halloysite-rich clay, whereas adsorption onto kaolinite/illite is inhibited by electrostatic exothermic effects and the sorption is thermodynamically unfavorable. The kinetic study showed that the adsorption capacity of MB on halloysite is greater than on kaolinite. The intraparticle diffusion process controls the adsorption reaction, and the kinetic is more important for halloysite.

The Black Steel slag (Ss) and phosphogypsum (PG) are industrial wastes produced in Morocco. In order to reduce these two wastes and to evaluate their pozzolanic reactivity in the presence of water, they were incorporated into bentonite (B) mixed with lime (L). The studied mixtures (BLW, BL-PG-W and BL-PG-Ss-W) were analyzed by X-ray diffraction, Infrared spectroscopy, Raman spectroscopy and SEM/EDX analysis. Compressive strength tests were performed on hardened specimens. The results obtained show that the hydration kinetics of the B-L-W and B-L-PG-W mixtures are slow. The addition of PG to a bentonite-lime mixture induces the formation of new microstructures such as hydrated calcium silicate (C-S-H) and ettringite, which increases the compressive strength of the cementitious specimens. The addition of the Ss to a mixture composed by 8%PG and 8%L-B accelerates the kinetics of hydration and activates the pozzolanic reaction. The presence of C2S in the slag helps to increase the mechanical strength of the mixture B-L-PG-Ss. The compressive strength of the mixtures BL-W, BL-PG-W and BL-PG-Ss-W increases from 15 to 28 days of setting. After 28 days of setting, 8% of Sc added to the mixture 8% PG-8%L-B is responsible for an increase of the compressive strength to 0.6 MPa.