Adsorption of Thymol onto Natural Clays of Morocco: Kinetic and Isotherm Studies (original) (raw)

ADSORPTION STUDY OF THYMOL ON NA-BENTONITE

This paper presents the study of adsorption of thymol on a clay support (bentonite). The clay used was collect- ed from the province of Nador (North-East of Morocco). The clay was purified and doped with sodium prior to use. The obtained adsorption isotherm presents a Langmuir type for low values of equilibrium concentration with a rise of the isotherm showing a certain affinity of thymol for anionic clay sites. The adsorbed amount of thymol determined at the plateau of the isotherm was 177 mg per gram of sodium clay. The adsorption kinetic was described successfully using a pseudo-second-order rate equation, and the adsorption was rapid with 90 % of the thymol adsorbed within the first 20 min.

Comparison of Phenol Adsorption Property and Mechanism onto Different Moroccan Clays

Water

This study focuses on the removal of phenol from aqueous media using Agouraï clay (Fes-Meknes-Morocco region) and Geulmima clay (Draa Tafilalet region). The characterization of the clay by Fourier Transform Infrared (FTIR) Spectroscopy, X-ray diffraction (XRD), N2 adsorption (BET), Scanning Electron Microscopy (SEM), and Thermogravimetric and differential thermal analysis (DTA/GTA) indicates that it is mainly composed of quartz, kaolinite, and illite. The results showed that raw Clay Agourai (RCA) and raw Clay Geulmima (RCG) adsorbed phenol very quickly and reached equilibrium after 30 min. Thermodynamic parameters reveal the physical nature of the adsorption, the spontaneity, and the sequence of the process. However, the structure and structural characterization of the solid before and after phenol adsorption indicated that the mechanism of the reaction was electrostatic and that hydrogen bonding played an important role in RCG, while kinetic modeling showed the pseudo-second-order...

Adsorption of Lippia multiflora essential oil on two surfactant modified clays: qualitative approach

Clay Minerals

This paper deals with the adsorption of an essential oil (EO) on a kaolinite-rich clay and a smectite-rich clay. The two clays were modified with a quaternary alkyl ammonium surfactant to create a lipophilic environment for better adsorption of the EO. The preparation of the clay/EO hybrids avoided the use of a slurry and organic solvent. The selected EO was that of Lippia multiflora. This EO has insecticidal properties. The surfactant was trioctyl methylammonium (TOMA). The modified clays were characterized by X-ray diffraction (XRD) and infrared (IR) spectroscopy. The smectite-rich clay displayed greater adsorption of the L. multiflora EO compared to the kaolinite-rich clay. The interlayer space of the kaolinite-rich clay was not affected by the adsorption of the TOMA and/or EO molecules, which suggests that the adsorption in this clay took place on the external surface. By contrast, a significant increase in the interlayer space of the smectite-rich clay was observed, suggesting ...

Chemical characterization and adsorption of oil mill wastewater on Moroccan clay in order to be used in the agricultural field

Heliyon, 2020

Oil mill wastewater (OMW) is the main liquid discharge from oil mills, it is considered as a dangerous pollutant due to its toxic chemical compounds which are unloaded directly in the environment without any treatment. The aims of this study were to evaluate the effectiveness of OMW adsorption on clay as a good method for the elimination of toxic chemical compounds and to study the application of treated OMW as an irrigation source in agricultural field. For this, Clay was collected from the city of Agourai (Meknes region, Morocco) and characterized by X-ray diffraction, X-ray fluorescence spectrometry, BET and FTIR analysis. Moreover, the treated OMW was analyzed using UHPLC-ESI-MS and the determination of total phenolic content (TPC) was also performed. However, the application of the treated OMW in agricultural field was performed by the determination of its effect on the germination of Lepidium sativum seeds (in vitro) and as a source of irrigation of Vicia faba plants (in situ). The results of this study showed that OMW had the following physicochemical characteristics: average pH of 4.88, TPC of 4.75 g/l, COD of 80 g/l, BOD5 of 18.72 g/l, conductivity of 16.05 cm-1, dry matter of 135.7 g/l and volatile matter of 58.7 g/l. The adsorption on clay had increased the pH from 4.88 to 6.14 and reduced significantly the organic matter (42% of COD and 57.4% of phenolic compounds). UHPLC-ESI-MS analysis showed the presence of a wide variety of organic compounds in OMW, with the appearance of new compounds after adsorption. Moreover, the use of treated OMW as a source of irrigation showed a significant effect on the germination of Lepidium sativum seeds and the growth of Vicia faba plants. From this study, we can conclude that the adsorption on clay is a good method for the treatment of OMW, which became non-toxic for environment and can be used as a source of irrigation in agricultural field.

Characterization of inorganic and organic clay modified materials: An approach for adsorption of an insecticidal terpenic compound

Applied Clay Science, 2015

Two organic molecules and two inorganic polymers have been used to modify the structure of bentonites as to obtain a high adsorption capacity of thymol, an insecticidal terpenic compound. The selected organic molecules were cetyl and phenyl trimethyl ammonium chlorides (CTMA and PTMA); the inorganic compounds were aluminium hydroxyl and iron hydroxyl polymers. Organic bentonites were obtained after treatment with CTMA and PTMA solutions. Inorganic bentonites were obtained after treatment with polymeric solutions of Al x (OH) y and Fe x (OH) y . Materials were characterized by several physicochemical techniques including X-ray diffraction (XRD), thermal gravimetric and differential analysis (TGA, TDA), infrared spectroscopy (FTIR) and nitrogen adsorption-desorption. Adsorption capacities of modified and unmodified bentonites for terpenic compounds were also carried out. Results show that the organic cations have been intercalated successfully into the bentonite interlayer space. XRD measurements show that PTMA and CTMA induce an interlayer space expansion of 4.1 Å and 10.5 Å, respectively. The increase of specific surface areas (SSA) of materials treated with metallic polycations attests the occurrence of exfoliation. The highest adsorption capacity of thymol is obtained with bentonites modified by alkylammonium, which proves that the modification of the interlayer space is an interesting way to improve adsorption properties of clays usable as support for natural insecticides.

Adsorption of Carvone and Limonene from Caraway essential oil onto Tunisian montmorillonite clay for pharmaceutical application

Scientific Reports

To explore a novel kind of green composite material having excellent antibacterial, antifungal ability and specific-targeting capability for pharmaceutical uses, a novel kind of bio-composite was prepared using sodium purified clay as carrier of Caraway essential oil (CEO). Gas chromatography-mass spectroscopy (GC–MS) analyses of CEO reveals that Carvone (68.30%) and Limonene (22.54%) are the two major components with a minimum inhibitory concentration (MIC) value equal to 125 mg/mL against Staphylococcus (S) aureus bacteria and Candida albicans fungi. Clay from Zaghouan was purified and characterized by X-ray Photoelectron Spectroscopy (XPS), X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR) and N2 adsorption–desorption (BET method). Results obtained by chromatograph equipped with a flame ionization detector (GC-FID) show that the concentration of 130 mg/mL of essential oil and 5 h of contact with the purified clay are the optimal conditions for the bio-hyb...

Asemi-Empirical Study of the Adsorption of Some Organic Pollutants on Modified Iraqi Clays

Baghdad Science Journal, 2016

In this work semi–empirical method (PM3) calculations are carried out by (MOPAC) computational packages have been employed to calculate the molecular orbital's energies for some organic pollutants. The long– chain quaternary ammonium cations called Iraqi Clays (Bentonite – modified) are used to remove these organic pollutants from water, by adding a small cationic surfactant so as to result in floes which are agglomerates of organobentonite to remove organic pollutants. This calculation which suggests the best surface active material, can be used to modify the adsorption efficiency of aniline , phenol, phenol deriviatives, Tri methyl glycine, ester and pecticides , on Iraqi Clay (bentonite) by comparing the theoretical results with experimental results achived in previous experimental studies between some organic pollutants and modified bentonite by (1- Hexadecyl pyridinium bromide) (HDPYBr). The theoretical calculation is made by using three surface active materials [1- (Hexade...

Physicochemical Characterization of Regional Clay: Application to Phenol Adsorption

Applied and Environmental Soil Science, 2021

Phenol is one of the most toxic pollutants found in industrial waste. This work focuses on the removal of phenol using clay from the Sale region. Adsorbent was characterized by X-ray fluorescence spectroscopy, X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. The chemical analysis of this clay shows that the percentage of silicon and aluminium is quite high, and the percentage of calcium and iron is relatively high, so this material is rich in muscovite, quartz, and calcite. In addition to the presence of titanium dioxide (TiO2), which can give it a property of degradation of organic compounds under ultraviolet light, the pHPZC zero point of our material is 7.4. The results showed that the adsorption of phenol was well fitted by the pseudo-second-order kinetic model and the Langmuir and Freundlich isotherms and that the best retention is obtained at a pH between 3 and 8.

Study of the Adsorption of Bright Green by a Natural Clay and Modified

Journal of Material Science & Engineering, 2016

The adsorption of Bright Green (BG), a cationic dye, was studied by clay treatment experiments by modification with an aqueous solution of a cationic surfactant. Hexadecyltrimethylammonium bromide (HDTMA) and Cetylpyridinium chloride (CPC) were used for the modification of the clay. Clay modified HDTMA showed the greatest adsorption capacity compared to the other adsorbents studied. The adsorption of HDTMA on BG depended on the adsorbent dose, the pH of the solution, the contact time and the initial dye concentration studied. The adsorption data to correspond to the HDTMA experiments have been better described by the Langmuir isotherm model. The isothermal adsorption capacity of BG on HDTMA modified clay was found to be 45.5 mg/g (for an initial BG concentration of 50 mg/L), which is significantly higher than that of other adsorbents. The kinetics of adsorption of BG on clay modified by HDTMA has been described more precisely by the pseudo-second order kinetics model. The adsorbent was characterized by analysis of the Brunauer-Emmett-Teller surface (BET), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The BG adsorption mechanism on the surfactant-modified clay may comprise a hydrophobic interaction or van der Waals interaction or a combination of the two.

Adsorption of textile dyes on raw and decanted Moroccan clays: Kinetics, equilibrium and thermodynamics

Water Resources and Industry, 2015

Inexpensive and easily available Moroccan natural clays were investigated for the removal availability of textile dyes from aqueous solution. For this purpose, the adsorption of methylene blue (MB) as reference molecule, malachite green (MG) representative of cationic dyes and methyl orange (MO) representative of anionic dyes, was studied in batch mode under various parameters. The clays were characterized by means of XRD, cationic exchange capacity and BET surface area analysis. The experimental results show that, the adsorption was pH dependent with a high adsorption capacity of MB and MG in basic range and high adsorption of MO in acidic range. The pseudo-second-order kinetic model provided the best fit to the experimental data for the adsorption of MB and MG by the clays. However, the adsorption of MO was more suitable to be controlled by an intra-particle diffusion mechanism. The equilibrium adsorption data were analyzed by Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. The adsorption process was found to be exothermic in nature in the case of MB and MO. However, the adsorption of MG was endothermic.