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Five natural ceramic raw materials from three north-west Moroccan regions (Berrechid, Tiflet and Kemmiset), which are used in the ceramic industry, have been studied with the aim to devise other possible uses or optimize the mixture and thermal conditions for manufacturers. Chemical-physical and mineralogical characterization techniques (XRD, ESEM, FTIR, CEC, TGA, BET, etc.) have been applied either to compare the bulk, grinded (the fraction used in ceramic industry) and sieved materials or to understand their changes upon heating, at temperatures comparable with those applied in ceramic industry. The data indicate that the bulk and sieved materials do not show relevant differences. All the samples are composed for at least 20% wt of quartz, accompanied by a different amount of phyllosilicates. The Tiflet material has a higher content in calcite and dolomite, together with amount of feldspar, which makes this material of particular interest for ceramic industry. Feldspar is used in ceramic industry as fluxing agent inducing early vitrification, increasing the firing shrinkage and decreasing the firing temperatures. The 29Si and 27Al solid state nuclear magnetic resonance spectra recorded before and after heating evidenced the presence of new phases formed by the dehydroxylation and decarboxylation processes. The mineral transformations upon heating were studied also for the clays fraction by in-situ XRD technique. Complete chemical, morphological and mineralogical characterization of five natural clays, from three north-west Moroccan regions, before and after heating Unlabelled Image • Natural Moroccan clays: mineralogical and chemical characterization • 29Si and 27Al NMR in the solid state of clays before and after heating • XRD study during heating • BET determinations of natural Moroccan clays • Investigation of the modification of clays upon heating • Application of Environmental Scansion Electron Microscopy (ESEM) for morphological and chemical characterization [ABSTRACT FROM AUTHOR]

The removal of heavy metals from wastewater has become the subject of considerable interest at present. Thus, the use of novel adsorbents that are highly efficient is of critical importance for the removal of Cr (VI) ions from aqueous media. The adsorption of Cr (VI) ions from aqueous solutions by a new adsorbent, cedar wood sawdust, and the optimization of its adsorption parameters, were investigated in this study. Cedar wood sawdust was used in its native and HNO3/NaOH chemically modified forms as new low-cost sorbents to remove Cr (VI) ions from aqueous solutions in a batch system. The adsorption conditions were analyzed via response surface methodology. The RSM results showed that the optimal adsorption conditions yielding the best response were an adsorbent mass of 2 g for native Cedar and 1.125 g for its activated form, a metal concentration of 150 mg/L for native Cedar and 250 mg/L for activated, a temperature of 50 °C, a pH of 1, and a contact time of 67.5 min. At optimum adsorption conditions, the maximum adsorption capacities and the adsorption yields were 23.64 mg/g and 84% for native Cedar and 48.31 mg/g and 99% for activated Cedar, respectively. [ABSTRACT FROM AUTHOR]

• Industrial wood wastes cause oxidative stress in aquatic organisms. • The fish exposed to wood wastes have lethargic movements. • SOD, CAT and GTx activities increased significantly in fish exposed to sawdusts. • The excessive generation of reactive oxygen causes the membrane lipid lesions. The aquatic pollution due to sawmill wood wastes constitutes a major threat to hydro-chemical and fauna characteristics of the aquatic ecosystems. When this kind of organics wastes enter aquatic environment it can be taken up by aquatic organisms through respiration and/or through their diet. This could concurrently result in oxidative stress and later having adverse effect on physiological and biochemical function. The importance of fish in the society cannot be over emphasized, hence there is the need to know the influence of sawmill wood wastes on the water quality and fish. Therefore, this work aims to study the impact of five species of wood wastes on a type of fish named common carp (Cyprinus carpio) known as the most widely cultured fish species in the world and on its aquatic environment. The monitoring of water parameters showed deterioration in water quality. The activities of superoxide dismutase (SOD), Catalase (CAT), glutathione peroxidase (GPx) and lipid peroxidation (MDA) were investigated to evaluate the degree of oxidative stress. According to t-student, there was a significant difference compared to control (P < 0.05) in the level of SOD, CAT, GPx and MDA activities in fish exposed to 5 g·l−1 of each sawdust except for GPx, a non-significant difference (p > 0.05) was noted in the case of Beech and Dibetou. When the dispersed amount was about 0.375 g·l−1 we noted a significant difference in the level of SOD and GPx, except for GPx a non-significant difference was detected in the case of Cedar. The level of CAT was significantly difference just in the case of Cedar and Dibetou and that of MDA was significantly difference just in the case of Beech and Mahogany. We conclude therefore that sawmill wood waste not only impact the water quality adversely but also alters the levels of different enzymes activities in Cyprinus Carpio fish by the inhibition of SOD, CAT and GPx activities and by the production of MDA, which reflects response to oxidative stress. This study provides a rational use of these enzymes as suitable biomarkers with different degrees of specificity and as important tool for environmental monitoring. [ABSTRACT FROM AUTHOR]