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Study on Wastewater Treatment in the Textile Industry by Adsorption of Reactive Red 141 Dye Using a Phosphogypsum/ Vanadium Composite Developed from Phosphate Industry Waste

100%

Chajri F. Z. , Bensemlali M. , Hatimi B. , Sanad A. , Joudi M. , Abdellatif A. , Siniti M. , Bakasse M. , Baraket A. , Nasrellah H.

tom Vol. 25, iss. 7

46--62

A novel method has been explored based on the recovery of two industrial wastes V2 O5 and phosphogypsum from the fertilizer production industry, which also provide a significant challenge due to their toxicity and environmental impact. To solve the problem of these two harmful wastes, these residues have been transformed into valuable resources, by the elaboration of Nanoparticles vanadate-hydroxyapatite (NPs-HAP/VAP) adsorbent, contributing a sustainable solution without requiring expensive or highly skilled work. This comprehensive investigation explores the adsorption of the reactive red 141 dye (RR 141) on Ca10 (VO4 ) x (PO4 ) 6−x (OH) 2 , with (xi = 0, 1.5, 3, 4.5, and 6). Using a Centered composite design (CCD), several parameters influencing the adsorption process were examined. The optimal adsorption capacity is 50 mg. g – 1 under optimal conditions 57.5 mg of the adsorbent dose, 152.5 mgL-1 for the RR 141, pH 8, 92.5 minutes of contact time, and incorporation ratio of 4.5 with an R2 of 0.99. These results reinforce the effectiveness of our chosen CCD model. Kinetic analysis demonstrated a pseudoorder reaction model with an R2 ˃ 0.92, while the Sips isotherm describes the adsorption process. Thermodynamic studies revealed spontaneous adsorption, suggesting a physical character enhanced by a positive entropy variation.

Adsorption of ciprofloxacin from aqueous environment by using synthesized nanoceria

58%

Rahdar A. , Rahdar S. , Ahmadi S. , Fu J.

2019

tom Vol. 26, nr 2

299--311

Antibiotics are widely detected emerging contaminants in water environments and possess high potential risks to human health and aquatic life. However, conventional water treatment processes cannot remove them sufficiently. To develop innovative nanoadsorbents for effectively remove antibiotic contaminants from water environment, nanoceria were prepared via in situ precipitation method, and evaluated their adsorption capacity for a model antibiotic, ciprofloxacin (CIP). The properties of the prepared nanoceria were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and vibration sample magnetization (VSM). The effect of various operating parameters such as pH, initial CIP concentration, contact time, and adsorbent dosage on adsorptions of CIP were studied in batch experiments. Maximum adsorption capacity of the nanoceria was 49.38 mg/g at the conditions of pH 5, initial CIP concentration of 200 mg/dm3 and adsorbent dosage of 0.2 g/dm3, when 95.43 % of the CIP was removed. For adsorption kinetics, both pseudo-first-order and pseudo-second-order models can well describe the experimental data, indicating that the adsorption process was controlled by both physical diffusion and chemical interaction. For adsorption isotherms, the Freundlich model could fit the experimental data better than the Langmuir and Temkin models, suggesting a multilayer adsorption process. The thermal dynamics study showed the absorption process was spontaneity, exothermic, and irreversible. Finally it was concluded that the nanoceria can be used effectively for CIP removal.