New zeolite made from Tunisian raw clay: study and modeling for C3H6 breakthrough dynamic adsorption onto zeolite material.

In this study, Tunisian raw clay (RC) was utilized as a cheap source of silicium and aluminum for the preparation of faujasite zeolite (FAUsyn) using the alkaline fusion technique. The zeolite's structural analysis was carried out using the XRD, nitrogen adsorption-desorption, and SEM-EDX techniques. The data collected demonstrate that the produced zeolite only included one homogeneous faujasite phase. Textural analysis shows that the FAUsyn prepared from RC has a hierarchical porosity (micro-, meso-, and macropores). The total porosity was found to be 0.33 cm3/g as well as the BET area was equal to 360 m2/g. Adsorption experiments for propene capture were performed using the FAUsyn as adsorbent material. The performance of the column was examined in relation to various parameter impacts, including flow rate (50, 100, and 150 mL/min), input concentration (4, 8, and 12 mg/L), and bed depth (10, 14, and 18 cm). Finally, experimental and theoretical studies were investigated to predict adsorption capacities and kinetics parameters. To clarify and estimate column inputs, a model that incorporates axial dispersion, Langmuir equation, and migration within the adsorbent's pore was improved. COMSOL Multiphysics software was used to execute the model and resolve it computationally. The results of the experiments and the expected breakthrough curves were very well agreed. Modeling obtained results can be extrapolated to industrial level.

Sono-assisted adsorption of organic compounds contained in industrial solution on iron nanoparticles supported on clay: Optimization using central composite design.

Organic substance (O.S) in industrial phosphoric acid (IPA) solution is often tacked placed creates a major problem for IPA quality. This study was performed to assess the efficiency of Iron Intercalated Bentonite Nanoparticles (IIBN) coupled with the ultrasonic irradiation named sono-adsorption process for treating IPA 54% P2O5 contained O.S. XRD, SEM and BET were performed for the characterization of as-prepared adsorbent. Several conditions such as adsorbent dosage, molar ratio (OH/Fe) and time were investigated in retention experiments at acidic pH and T° of 40 ± 1 °C. The sono-assisted retention parameters were optimized by using NEMROOD software. The interaction impact of study condition on the final retention capability of the organism has been revealed by ANOVA software. Accordingly, the organic substance removal can be retained more than 83% by a sonication time of 0.5 h, absorbent dosage of 1.2 g/L and a molar ratio (OH/Fe) of 1.37. The absorbability of O.S was also evaluated by using the three parameters retention isotherms and kinetic analysis.

Sono-assisted adsorption of Cristal Violet dye onto Tunisian Smectite Clay: Characterization, kinetics and adsorption isotherms.

The present work describes the removal of Crystal violet from aqueous solution by Sono-assisted adsorption on Raw Tunisian Smectite Clay (RSC). This material was purified by dispersion in water and extraction of the fraction with a particle size smaller than 2 µm. the resulting material was characterized by XRD, TEM, BET, surface area and pore volume measurements. Batch studies were carried out to investigate the effect of experimental factors such as contact time (0-60 min), pH (2.5-11), adsorbent dose (0.05-0.3 g/L), and initial dye concentration (12.5-100 mg/L) on the Sono-assisted adsorption of Crystal violet dye. Adsorption kinetics was well fitted by pseudo-second order kinetic model. Langmuir (R2 = 0.988), Freundlich (R2 = 0.968), Langmuir-Freundlich (R2 = 0.997) and Toth (R2 = 0.999) isotherms were fitted to describe the equilibrium of Crystal violet Sono-assisted adsorption process. The results suggested that Natural Tunisian Smectite Clay is suitable as a sorbent material for Sono-assisted adsorption of Crystal violet dye from aqueous solutions.

Breakthrough modeling and experimental design for o-xylene dynamic adsorption onto clay material.

The adsorption of o-xylene onto raw clay material in a fixed bed using a thermal conductivity detector gas chromatography was investigated. Experimental and theoretical studies were established to evaluate the removal efficiency of o-xylene by adsorption on clay materials and to predict kinetic parameters. Column data were describing at different conditions using Bohart-Adams, Wolborska, Thomas, Yoon and Nelson, dose-response, and bed depth service time models. All used models were satisfactory to predict the breakthrough curves. A suitable advection-dispersion-sorption (ADS) model has been also developed to simulate the measured data, based on the nature of the various equilibrium relationships of solid-gas and diverse descriptions of the mass transfer processes within of the adsorbent particle. The experiments can be fitted with high correlated coefficient R 2 = 0.996.