scholarly journals Dyes Adsorption Behavior of Fe3O4 Nanoparticles Functionalized Polyoxometalate Hybrid

Molecules ◽  
2019 ◽  
Vol 24 (17) ◽  
pp. 3128 ◽  
Author(s):  
Jie Li ◽  
Chen Si ◽  
Haiyan Zhao ◽  
Qingxi Meng ◽  
Bowen Chang ◽  
...  
Keyword(s):  
Adsorption Kinetics ◽  
Removal Rate ◽  
Aqueous System ◽  
Blocking Temperature ◽  
Isotherm Models ◽  
Zero Field ◽  
Magnetic Adsorbent ◽  
Anionic Dyes ◽  
Desorption Process ◽  
Dyes Adsorption

The magnetic adsorbent, Fe3O4@[Ni(HL)2]2H2[P2Mo5O23]·2H2O (Fe3O4@1), is synthesized by employing the nanoparticles Fe3O4 and polyoxometalate hybrid 1. Zero-field-cooled (ZFC) and field-cooled (FC) curves show that the blocking temperature of Fe3O4@1 was at 120 K. Studies of Fe3O4@1 removing cationic and anionic dyes from water have been explored. The characterization of Fe3O4@1, effects of critical factors such as dosage, the concentration of methylene blue (MB), pH, adsorption kinetics, isotherm, the removal selectivity of substrate and the reusability of Fe3O4@1 were assessed. The magnetic adsorbent displayed an outstanding removal activity for the cationic dye at a broad range of pH. The adsorption kinetics and isotherm models revealed that the adsorption process of Fe3O4@1 was mainly governed via chemisorption. The maximum capacity of Fe3O4@1 adsorbing substance was 41.91 mg g−1. Furthermore, Fe3O4@1 showed its high stability by remaining for seven runs of the adsorption-desorption process with an effective MB removal rate, and could also be developed as a valuable adsorbent for dyes elimination from aqueous system.

scholarly journals Effect of The Surfactant Loaded Amount Into The Bentonite on The Elimination of Two Anionic Dyes: Adsorption, Kinetics, and Isotherm Studies

2021 ◽  
Author(s):  
Brahim Guezzen ◽  
Mehdi Adjdir ◽  
Abdelkader Elaziouti ◽  
Mohamed Amine Didi
Keyword(s):  
Adsorption Capacity ◽  
Adsorption Kinetics ◽  
Indigo Carmine ◽  
Exchange Capacity ◽  
Hexadecyltrimethylammonium Bromide ◽  
Anionic Dyes ◽  
Intra Particle Diffusion ◽  
Pseudo Second Order ◽  
Dyes Adsorption ◽  
Adsorption Kinetics And Isotherm

Abstract The present work focused on the preparation of hybrid-bentonite adsorbents by treating sodium bentonite (Na-B) with different amounts of hexadecyltrimethylammonium bromide (HDTMA+ Br-), corresponding to 50, 100 and 200% the value of the cation exchange capacity (CEC). The samples prepared, namely 50HDTMA-B, 100HDTMA and 200HDTMA-B, were characterized by different techniques including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA ). The removal efficiency of two anionic dyes, namely. Congo Red (CR) and Indigo Carmine (IC), from aqueous solutions, was studied as a function of the amount of HDTMA, contact time, hybrid adsorbent and initial dye concentration. In addition, a kinetic study was conducted to fit the experimental data in order to compare the adsorption rate constants and the equilibrium sorption capacities of anionic dyes on the prepared materials. The results obtained indicated that the adsorption kinetics of clay samples could be best described by the pseudo-second-order model, and the adsorption capacity of the hybrid-Bentonite is affected by the amount of modifier used. Based on Weber-Morris intra-particle diffusion equation, it was found that the CR and IC dyes diffused faster as the cationic surfactant loading increased from 0 to 100% of the CEC value. The Langmuir isotherm exhibited the best fit, with an adsorption capacity equal to 292 and 289 mg g-1, for CR and IC dyes, respectively.

scholarly journals Preparation and Characterization of Cationized Cellulose for the Removal of Anionic Dyes

2001 ◽  
Vol 19 (3) ◽  
pp. 197-210 ◽  
Author(s):  
A. Hashem ◽  
Reda M. El-Shishtawy
Keyword(s):  
Adsorption Capacity ◽  
Freundlich Isotherm ◽  
Structural Features ◽  
Isotherm Models ◽  
Acid Orange 7 ◽  
Anionic Dyes ◽  
Adsorption Parameters ◽  
Direct Blue ◽  
Equilibrium Data

The factors influencing the cationization of microcrystalline cellulose with 3-chloro-2-hydroxypropyl triethylammonium chloride in the presence of NaOH were investigated. The course of the reaction was followed by estimating the nitrogen content of the cationized product while its structural features were confirmed by IR analysis. The ability of cationized cellulose to adsorb anionic dyes, viz. Acid Orange 7, Direct Blue 75 and Direct Violet 31, was investigated at 25°C and 50°C. The equilibrium data obtained were fitted by the Langmuir and Freundlich isotherm models, allowing the corresponding adsorption parameters to be determined. The results showed that the adsorption capacity was dependent on the adsorbent, temperature, the nature of the dye and (to some extent) on van der Waals and hydrogen bonding. Cationized cellulose exhibited a much better adsorption capacity towards anionic dyes than cellulose.

scholarly journals Adsorption Characteristics of Phosphate Ions by Pristine, CaCl2 and FeCl3-Activated Biochars Originated from Tangerine Peels

Separations ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 32 ◽  
Author(s):  
Changgil Son ◽  
Wonyeol An ◽  
Geonhee Lee ◽  
Inho Jeong ◽  
Yong-Gu Lee ◽  
...  
Keyword(s):  
Adsorption Kinetics ◽  
Chemical Activation ◽  
Isotherm Models ◽  
Order Model ◽  
Phosphate Ions ◽  
Adsorption Capacities ◽  
Adsorption Isotherm Models ◽  
Endothermic Reactions ◽  
Pseudo Second Order ◽  
Adsorption Kinetics And Isotherm

This study has evaluated the removal efficiencies of phosphate ions (PO43−) using pristine (TB) and chemical-activated tangerine peel biochars. The adsorption kinetics and isotherm presented that the enhanced physicochemical properties of TB surface through the chemical activation with CaCl2 (CTB) and FeCl3 (FTB) were helpful in the adsorption capacities of PO43− (equilibrium adsorption capacity: FTB (1.655 mg g−1) > CTB (0.354 mg g−1) > TB (0.104 mg g−1)). The adsorption kinetics results revealed that PO43− removal by TB, CTB, and FTB was well fitted with the pseudo-second-order model (R2 = 0.999) than the pseudo-first-order model (R2 ≥ 0.929). The adsorption isotherm models showed that the Freundlich equation was suitable for PO43− removal by TB (R2 = 0.975) and CTB (R2 = 0.955). In contrast, the Langmuir equation was proper for PO43− removal by FTB (R2 = 0.987). The PO43− removal efficiency of CTB and FTB decreased with the ionic strength increased due to the compression of the electrical double layer on the CTB and FTB surfaces. Besides, the PO43− adsorptions by TB, CTB, and FTB were spontaneous endothermic reactions. These findings demonstrated FTB was the most promising method for removing PO43− in waters.

Removal of Dyes from Aqueous Solutions by Adsorption on Chrome-Tanned Solid Wastes Generated in the Leather Industry

2003 ◽  
Vol 38 (2) ◽  
pp. 393-411 ◽  
Author(s):  
Soufiane Tahiri ◽  
Ali Messaoudi ◽  
Abderrahman Albizane ◽  
Mohamed Azzi ◽  
Mohamed Bouhria ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Operating Conditions ◽  
Solid Wastes ◽  
Cationic Dyes ◽  
Optimum Operating ◽  
Leather Industry ◽  
Anionic Dyes ◽  
Ph Values ◽  
Acidic Conditions ◽  
Dyes Adsorption

Abstract In this work, the ability of chrome shavings and of crust leather buffing dusts to remove dyes from aqueous solutions has been studied. Buffing dusts proved to be a much better adsorbent than chrome shavings for cationic dyes. The adsorption of anionic dyes is very important on two studied wastes. The pH has an obvious influence on the adsorption of dyes. Adsorption of cationic dyes is less favourable under acidic conditions (pH <3.5) and at high pH values (pH >10.5). The adsorption of anionic dyes on both adsorbents is more favourable under acidic conditions (pH <3). The adsorption on chrome shavings is improved by the use of finer particles. The kinetic adsorption was also studied. Adsorption isotherms, at the optimum operating conditions, were determined. Adsorption follows the Langmuir model. The isotherm parameters have been calculated. The column technique could be applied to treat significant volumes of solutions.

scholarly journals Adsorption of tetracycline by a tailor- made adsorbent in aqueous system

2019 ◽  
Vol 6 (1) ◽  
pp. 30-36
Author(s):  
Adelagun Ruth Olubukola Ajoke ◽  
Neelam Yadav ◽  
Ajar Nath Yadav
Keyword(s):  
Municipal Wastewater ◽  
Growth Promotion ◽  
Active Form ◽  
Animal Husbandry ◽  
Freundlich Isotherm ◽  
Aqueous System ◽  
Isotherm Models ◽  
Municipal Wastewater Treatment ◽  
Input Concentration ◽  
Modified Chitosan

Tetracyclines are frequently used antibiotics for growth promotion and therapeutic pharmaceuticals both by humans and animal husbandry, and commonly encountered in municipal wastewater treatment plants and in the environment in their active form. This implies their continuous release into the environment may facilitate toxic effects both on humans and the environment including development of resistance strains, among others. This research was focused on the synthesis, characterisation and assessment of a tailor- made adsorbent: modified chitosan flakes, using several materials for the modification of chitosan to enhance its sorption properties thereby facilitating a higher percentage of TC removal from a synthetic pharmaceutical wastewater. TC adsorption onto the modified chitosan flakes was relatively fast (equilibrium time = 2h). Sorption studies revealed that TC removal by the adsorbent followed pseudo second order kinetics and Freundlich isotherm models. At higher TC input concentration, the amount of TC removed was also higher, this implied the sorption was concentration dependent. Insight into mechanism of sorption revealed cation exchange was an active means of interaction between the adsorbate and adsorbents moieties.

scholarly journals Investigation of competitive adsorption and desorption of heavy metals from aqueous solution using raw rock: Characterization kinetic, isotherm, and thermodynamic

2021 ◽  
Vol 348 ◽  
pp. 01016
Author(s):  
Rajaa Bassam ◽  
Marouane El Alouani ◽  
Nabila Jarmouni ◽  
Jabrane Maissara ◽  
Mohammed El Mahi Chbihi ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Adsorption Process ◽  
Freundlich Isotherm ◽  
Langmuir Model ◽  
Second Order ◽  
Isotherm Models ◽  
Desorption Process ◽  
Pseudo Second Order ◽  
Rock Characterization ◽  
Metals Adsorption

Heavy metals are the most dangerous inorganic pollutants Due to their bioaccumulation and their nonbiodegradability, for this, several studies have focused on the recovery of these metals from water using different techniques. In this context, our study consists of evaluating an efficient and eco-friendly pathway of competitive recovery of heavy metals (Cd, Cr and As) from aqueous solutions by adsorption using raw rock. This adsorbent was characterized before and after the adsorption process by several techniques. The multi-metals adsorption process in the batch mode was undertaken to evaluate the effect of adsorbent mass, contact time, pH, Temperature, and initial heavy metals concentration. The kinetic data were analyzed using the pseudo-first-order, pseudo-second-order and intra-particle diffusion kinetic models. According to the modeling of the experimental results, the adsorption kinetics of heavy metals were adapted to the pseudo-second-order model. The adsorption isotherms were evaluated by the Langmuir and Freundlich isotherm models. The experimental isotherm data of heavy metals were better fitted with the Langmuir model rather than Freundlich isotherm models. The maximum experimental adsorption capacities (Qmax) predicted by the Langmuir model are 15.23 mg/g for Cd (II), 17.54 mg/g for Cr (VI) and 16.36 mg/g for As (III). The values of thermodynamic parameters revealed that the heavy metals adsorption was exothermic, favorable, and spontaneous in nature. The desorption process of heavy metals showed that this raw rock had excellent recycling capacity. Based on the results, these untreated clays can be used as inexpensive and environmentally friendly adsorbents to treat water contaminated by heavy metals.

Adsorption kinetics and isotherm of anionic dyes onto organo-bentonite from single and multisolute systems

2009 ◽  
Vol 172 (1) ◽  
pp. 99-107 ◽  
Author(s):  
Dazhong Shen ◽  
Jianxin Fan ◽  
Weizhi Zhou ◽  
Baoyu Gao ◽  
Qinyan Yue ◽  
...  
Keyword(s):  
Adsorption Kinetics ◽  
Anionic Dyes ◽  
Adsorption Kinetics And Isotherm
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