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The highly colored textile effluents require efficient treatment before being released into the environment. In this study, a continuous-flow single-channel reactor operating in closed- circuit was used to apply electrocoagulation for the treatment of synthetic textile wastewater. First, the characterization of the hydrodynamic within the reactor is evaluated by Computational Fluid Dynamics simulation using the k-ε turbulence model (Comsol Multiphysics®). Apart from a non-uniform distribution of the velocities inside the reactor, no particular anomaly was observed. Second, the decolorization efficiency was examined under various current intensities, electrolysis times, and initial dye concentrations. By operating under a current intensity of 100 mA instead of 50 mA, the required electrolysis time to achieve a decolorization efficiency of 80% decreased by 40%, while the specific electrode consumption remained slightly unchanged at about 0.19 kg Al·kg−1. At a current intensity of 100 mA and an electrolysis time of 26 min, and the increase in the initial dye concentration from 10 to 50 mg·L−1 the decolorization efficiency decreased remarkably while the specific electrode consumption was kept constant at about 0.15 kg Al·kg−1 dye removed. The knowledge obtained through this study can be used for the transposition from batch to continuous mode. HIGHLIGHTS The EC process was carried out in a recirculation mode.; Comsol Multiphysics was used to perform CFD simulation in order to investigate the transport phenomenon in the CFSC reactor.; The RTD study is used to validate the numerical results obtained by CFD simulation.; The current intensities applied are far lower than in a conventional EC cell.; 0.15 kg/kg was considered to be the limit value of the specific electrode consumption.;

A remarkable growth was noticed in the development of molecularly imprinted polymers (MIPs), which have used as efficient synthetic antibodies that contain selective cavities to the target molecule. Hereunder, a novel strategy using MIP as a sorbent in solid-phase extraction was coupled to a fluorescence method for ellagic acid (EA) purification and immediate detection. The synthesis of magnetic-MIP (MMIP) using a rapid and green ultrasound technology was assessed by central composite design to determine the optimal polymerization conditions for a high-imprinting polymer. The MMIP was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and scanning/transmission electron microscopy, which accurately confirmed the functional, magnetic, and morphological features of MMIP. The prepared MMIP was demonstrated to be selective for EA compared to many similar phenols. The spectrofluorometric method showed a linear range from 0.05 to 2 μg·mL−1 of EA, and the limits of detection (LOD) and quantification (LOQ) were 0.005 and 0.02 μg·mL−1, respectively. Besides, the novel proposed smartphone method using the ultraviolet lamp as the excitation source presented a linear range from 0.2 to 4 μg·mL−1, a LOQ of 0.2 μg·mL−1, and a LOD of 0.07 μg.mL−1. The proposed strategy revealed high efficiency in the extraction and detection of EA in grape, redberry, and green tea. Effectively, the calculated recoveries were ranging from 80 to 102% with low values of relative standard deviation (

This work investigated the coagulation-flocculation (CF) process of Reactive Black-5 (RB5) dye. The individual effects and interactions of different parameters, which include the pH, coagulant (Ferric chloride), and flocculant dosage (Himoloc DR3000), on the removal efficiency of RB-5 dye were studied. This study aims to build a mathematical model that allows for the representation of the studied responses according to different factors by using the experimental design methodology. The statistical fitness of the developed model was checked using analysis of variance (ANOVA). A second-order quadratic model, with a high determination coefficient (R2 =0.98% and R2=0.80% for chemical oxygen demand (COD) removal and overall cost, respectively), was best fitted to develop the relationship between independent and dependent variables. The results obtained show that the model was highly significant and in good agreement with the experimental results. The optimum conditions obtained for coagulant dose, flocculant dose, and pH were 550 mg/l, 210 mg/l, and 5.4, respectively. Under these optimal conditions, about 98% COD removal and 3.12 $/m3 for effluent treatment were achieved.

There is an increasing interest in food science for high-quality natural products with a distinct geographical origin, such as saffron. In this work, the excitation-emission matrix (EEM) and synchronous fluorescence were used for the first time to geographically discriminate between Moroccan saffron from Taroudant, Ouarzazate, and Azilal. Moreover, to differentiate between Afghan, Iranian, and Moroccan saffron, a unique fingerprint was assigned to each sample by visualizing the EEM physiognomy. Moreover, principal component analysis (LDA) and linear discriminant analysis (LDA) were successfully applied to classify the synchronous spectra of samples. High fluorescence intensities were registered for Ouarzazate and Taroudant saffron. Yet, the Azilal saffron was distinguished by its low intensities. Furthermore, Moroccan, Afghan, and Iranian saffron were correctly assigned to their origins using PCA and LDA for different offsets (Δλ) (20–250 nm) such that the difference in the fluorescence composition of the three countries’ saffron was registered in the following excitation/emission ranges: 250–325 nm/300–480 nm and 360–425 nm/500–550 nm. These regions are characterized by the high polyphenolic content of Moroccan saffron and the important composition of Afghan saffron, including vitamins and terpenoids. However, weak intensities of these compounds were found in Iranian saffron. Furthermore, a substantial explained variance (97–100% for PC1 and PC2) and an important classification rate (70–90%) were achieved. Thus, the non-destructive applied methodology of discrimination was rapid, straightforward, reliable, and accurate.

This work deals with oxygenated apatite synthesis from calcium chloride and phosphoric acid using a wet precipitation method. An experimental design is applied to precise the influence of the synthesis parameters (pH of the reaction medium, atomic ratio Ca/P of the reagents, concentration of the calcium solution (Ca2+), temperature of the reaction medium (T), and duration of the reaction (D)) on the chemical composition (Ca/P molar ratio, % O2, and % O22−). An empirical model was developed and validated by applying the ANOVA analysis incorporating the interaction effects of all parameters and optimized using the response surface methodology. A reproducible synthesis of more oxygenated apatite with speed of dissolution adaptable to that of the osseous neoformation and allowing a progressive diffusion of oxygenated species (Ca/P = 1.575) is attained.

Antiseptic apatite-based calcium phosphates were prepared as the single-phase powders. Phosphocalcic oxygenated apatites were synthesized from calcium salts and orthophosphate dissolved in oxygenated water solution at 30%, under the biomimetic conditions of 37 °C and pH 7.4. The characterization and chemical analysis of the synthesized biomimetic apatite powders were performed by scanning electron microscopy (SEM), powder X ray diffraction (XRD), Fourier-transformed infrared spectroscopy (FT-IR) and chemical analysis. The obtained materials are a calcium deficient apatites with different morphologies.