New Ethylenediamine Crosslinked 2D-Cellulose Adsorbent for Nanoencapsulation Removal of Pb (II) and Cu (II) Heavy Metal Ions: Synthesis, Characterization Application, and RSM-Modeling

The main objective of the present work is to elaborate on a new eco-friendly and efficient adsorbent designated for aquatic micropollutants removal. However, the synthesis of the Ethylenediamine Crosslinked 2D-Cellulose green adsorbent was carried out successfully, by partial grafting of benzyl entities onto hydroxyl groups of HEC, and crosslinking with ethylenediamine ED. Further, the new ethylenediamine crosslinked 2D-Cellulose was used as a biosorbent for nanoencapsulation removal of copper and lead heavy metal ions from aqueous solutions. The proposal chemical structures of unmodified and modified materials were confirmed using FTIR, XRD, TGA, and SEM–EDX analysis. Furthermore, many parameters of the optimization for Pb (II) and Cu (II) in terms of removal efficiency including pH, adsorbent amount, and contact time were optimized by response surface methodology with a Box–Behnken design. Based on the desirability optimization with three factors, the maximal removal was 99.52% and 97.5% for Pb(II) and Cu(II), respectively and was obtained at pH = 5.94, 22.2 mg as the optimal adsorbent amount, and 21.53 min as contact time

Granulats à base de boues de phosphates : transformations thermiques, propriétés physiques et application

Phosphate sludge generated from beneficiation plants of Moroccan phosphate rocks was investigated at the range [900-1200°C] by X-ray diffraction, scanning electron microscopy, thermal analysis dilatometric analysis and impedance spectroscopy. Mixtures of the phosphates ludge and amendments such as a swelling clay (up to 30 wt.% of the clay), a kaolinitic clay (up to 40 wt.% of the sludge) and a fly ash (65.5 wt.% of the ash) were investigated and their properties (shrinkage, density, water absorption and compressive strength) were measured as a function of temperature and clay addition. The results showed that gehlénite neoformed from lime of decomposed carbonates and breakdown products of clay minerals in the first mixture while labradorite/anorthite was the only neoformed phase in the other blends. Also fluoroapatite (original mineral) resisted heating until fusion in almost samples. A new approach based on the methodology of the experimental design was adopted to assess the effect of the processing factors on the studied properties. The measured properties were mainly controlled by temperature, and the effect of clay addition was less regular. Considering the mixtures densities lightweight agglomerates can be produced at specific conditions. On the other hand, the release ability of phosphorus by LWAs in the presence ofalfalfa plants has been performed. It was found that due to the release of phosphorus by soil embedded pellets the growth of alfalfa plants improved. The sintering process of blends of phosphate sludge and a naturally occurring clay material (0-30 wt.%) was investigated in the range 650-1100°C by using impedance spectroscopy. The results showed that the sintering process was effective between 750 and 1000°C and occurred by melt flow.Des agrégats à base des boues de phosphate de la zone de Gantour ( Youssoufia,Maroc) sont cuits à des températures comprises entre 900 et 1200°C, et examinés par différentes techniques (DRX, MEB, analyses thermique et dilatométrique, et spectroscopie d’impédance). Les propriétés physiques des agrégats (retrait, absorption d’eau et résistance à la compression) sont mesurées et corrélées, dans certains cas, aux facteurs expérimentaux(température, temps de cuisson, teneur de l’additif), et ce en utilisant la méthodologie de la recherche expérimentale.Les agrégats amendés à l’argile smectitique sont le siège de formation de la gehlénite. Dans ce cas, la fluorapatite a partiellement résisté au traitement thermique, et a été le siège d’une ségrégation localisée. Les mesures d'impédance ont bien mis en évidence l'étape principale du frittage, lequel s’est produit par écoulement de la masse fondue. En se basant sur les valeurs de la densité, les granulats cuits à 900 et à 1100°C pouvaient bien être considérés comme des agrégats légers.Les études menées sur les agrégats des mélanges : argile kaolinitique-boue, cendre boue,et argile kaolinitique-cendre-boue ont montré la présence de la labradorite, et d’une masse fondue, qui semblait se former, entre autres, de la fusion de la fluorapatite. Par ailleurs,l'utilisation de la méthodologie de la recherche expérimentale a permis d'évaluer le poids des effets des facteurs expérimentaux sur les propriétés physiques des agrégats. Des granulats légers (1,02 < densité < 2,1 g/cm3) et résistants sont préparés avec succès dans les conditions expérimentales adoptées. Les granulats ayant le meilleur rapport résistance / densité sont ceux du mélange ternaire.Concernant le volet application, les résultats ont montré que l’utilisation des agrégats en construction est possible et que l’association d’agrégats légers au sol a permis d’activer la croissance des plants de la luzerne. D’un autre côté, l'absorption du phosphore par les racines(1,45 mg/g maximum) des plantes était meilleure dans le cas du mélange contenant de l’argile

Aggregates based phosphate sludge : thermal transformations, physical properties, and application

Des agrégats à base des boues de phosphate de la zone de Gantour ( Youssoufia,Maroc) sont cuits à des températures comprises entre 900 et 1200°C, et examinés par différentes techniques (DRX, MEB, analyses thermique et dilatométrique, et spectroscopie d’impédance). Les propriétés physiques des agrégats (retrait, absorption d’eau et résistance à la compression) sont mesurées et corrélées, dans certains cas, aux facteurs expérimentaux(température, temps de cuisson, teneur de l’additif), et ce en utilisant la méthodologie de la recherche expérimentale.Les agrégats amendés à l’argile smectitique sont le siège de formation de la gehlénite. Dans ce cas, la fluorapatite a partiellement résisté au traitement thermique, et a été le siège d’une ségrégation localisée. Les mesures d'impédance ont bien mis en évidence l'étape principale du frittage, lequel s’est produit par écoulement de la masse fondue. En se basant sur les valeurs de la densité, les granulats cuits à 900 et à 1100°C pouvaient bien être considérés comme des agrégats légers.Les études menées sur les agrégats des mélanges : argile kaolinitique-boue, cendre boue,et argile kaolinitique-cendre-boue ont montré la présence de la labradorite, et d’une masse fondue, qui semblait se former, entre autres, de la fusion de la fluorapatite. Par ailleurs,l'utilisation de la méthodologie de la recherche expérimentale a permis d'évaluer le poids des effets des facteurs expérimentaux sur les propriétés physiques des agrégats. Des granulats légers (1,02 < densité < 2,1 g/cm3) et résistants sont préparés avec succès dans les conditions expérimentales adoptées. Les granulats ayant le meilleur rapport résistance / densité sont ceux du mélange ternaire.Concernant le volet application, les résultats ont montré que l’utilisation des agrégats en construction est possible et que l’association d’agrégats légers au sol a permis d’activer la croissance des plants de la luzerne. D’un autre côté, l'absorption du phosphore par les racines(1,45 mg/g maximum) des plantes était meilleure dans le cas du mélange contenant de l’argile.Phosphate sludge generated from beneficiation plants of Moroccan phosphate rocks was investigated at the range [900-1200°C] by X-ray diffraction, scanning electron microscopy, thermal analysis dilatometric analysis and impedance spectroscopy. Mixtures of the phosphates ludge and amendments such as a swelling clay (up to 30 wt.% of the clay), a kaolinitic clay (up to 40 wt.% of the sludge) and a fly ash (65.5 wt.% of the ash) were investigated and their properties (shrinkage, density, water absorption and compressive strength) were measured as a function of temperature and clay addition. The results showed that gehlénite neoformed from lime of decomposed carbonates and breakdown products of clay minerals in the first mixture while labradorite/anorthite was the only neoformed phase in the other blends. Also fluoroapatite (original mineral) resisted heating until fusion in almost samples. A new approach based on the methodology of the experimental design was adopted to assess the effect of the processing factors on the studied properties. The measured properties were mainly controlled by temperature, and the effect of clay addition was less regular. Considering the mixtures densities lightweight agglomerates can be produced at specific conditions. On the other hand, the release ability of phosphorus by LWAs in the presence ofalfalfa plants has been performed. It was found that due to the release of phosphorus by soil embedded pellets the growth of alfalfa plants improved. The sintering process of blends of phosphate sludge and a naturally occurring clay material (0-30 wt.%) was investigated in the range 650-1100°C by using impedance spectroscopy. The results showed that the sintering process was effective between 750 and 1000°C and occurred by melt flow

Phosphate sludge-based ceramics: Microstructure and effects of processing factors

International audienceThe potential use of clay amended phosphate sludge in lightweight aggregates manufacturing was assessed. For this purpose, the microstructure of heated blends was examined with X-ray diffraction, thermal analysis and scanning electron microscope and impedance spectroscopy, and their physical properties were followed as a function of heating temperature, soaking time and clay content. For the latter study, the full factorial design was used. The results showed that phase neoformation involved the breakdowns of the clay minerals and lime of carbonates. Moreover, the sintering process was significant as the clay content exceeded 5 wt% and 900< T< 1000 degrees C. In such a condition, the sintering was chiefly controlled by melt. The results of the full factorial design showed that the increase of one of the processing factors affected positively water absorption, density and compressive strength. These effects were mainly linked to the conjugate formations of calcaluminosilicate and viscous phase. The results also pointed out that the effects of the interactions between the factors on the measured properties were almost negligible. By using the full factorial design, the optimum values of the physical properties were evaluated

Phosphate Mine Tailing Recycling in Membrane Filter Manufacturing: Microstructure and Filtration Suitability

Ceramic membrane filters based on industrial by-products can be considered to be a valorization alternative of phosphate mine tailings, even more so if these ceramic membranes are used in the industrial wastewater treatment due to their good mechanical, chemical, and thermal resistance. The depollution of textile industry rejections with this method has not been studied in detail previously. In this work, ceramic membrane filters have been manufactured from natural clay and phosphate mine tailings (phosphate sludge). Blends of the abovementioned materials with a pore-forming agent (sawdust, up to 20 wt. %) were investigated in the range 900&#8722;1100 &#176;C using thermal analysis, X-ray diffraction, scanning electron microscopy, and mercury porosimetry. Ceramic properties were measured as a function of firing temperature and sawdust addition. Filtration tests were carried out on samples with advantageous properties. The results showed that gehlenite together with diopside neoformed from lime decomposed carbonates and breakdown products of clay minerals, while calcium phosphate derived from partial decomposition of fluorapatite. Both quartz and fluorapatite resisted heating. The results of the experimental design showed that the variations of physical properties versus processing factors were well described by the polynomial model. Filtration results are quite interesting, allowing these membranes to be used in industrial effluent treatment