Adsorptive removal of congo red dye from aqueous solutions using Mo-doped CoFe2O4 magnetic nanoparticles

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ibrahim A. Amar ◽  
Jawaher O. Asser ◽  
Amina S. Mady ◽  
Mabroukah S. Abdulqadir ◽  
Fatima A. Altohami ◽  
...  

Purpose The main purpose of this paper is to investigate the adsorption properties of CoFe1.9Mo0.1O4 magnetic nanoparticles (CFMo MNPs) using, anionic dye “congo red (CR)” as a model of water pollutants. Design/methodology/approach The magnetic nano-adsorbent was synthesized via sol-gel process. Different techniques including; Fourier transform infrared spectroscopy, point of zero charge, scanning electron microscope and X-ray powder diffraction were used to characterize the prepared adsorbent. Adsorption experiments were conducted in batch mode under various conditions (contact time, shaking speed, initial dye concentration, initial solution pH, solution temperature and adsorbent amount) to investigate the adsorption capability of CFMo MNPs for CR. Findings The results showed that, CFMo MNPs could successfully remove more than 90% of CR dye within 20 min. Adsorption kinetics and isotherms were better described using pseudo-second-order (PSO) and Langmuir models, respectively. The maximum adsorbed amount (qmax) of CR dye was 135.14 mg/g. The adsorption process was found to be endothermic and spontaneous in nature as demonstrated by the thermodynamics ( ΔGo, ΔHoand ΔSo). Practical implications This study provided a good example of using an easily separated magnetic nano-adsorbent for fast removal of a very toxic organic pollutant, congo red, from the aquatic environment Originality/value The employment of Mo-doped cobalt ferrite for the first time for removing hazardous anionic dyes such as congo red from their aqueous solutions.

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ibrahim A. Amar ◽  
Salma M. Hassan ◽  
Fatima H. Aqeela ◽  
Mohamed Y. Najem ◽  
Fatima A. Altohami

Purpose This paper aims to investigate the potential application of Balanites aegyptiaca bark powder (BABP) for removing a basic textile dye, methylene blue (MB), from aqueous solutions. Design/methodology/approach The biosorbent (BABP) was characterized using Fourier transform infrared spectroscopy (FTIR) and point of zero charge (pHPZC). Batch mode was selected to study the biosorption of MB onto BABP surface at different experimental conditions (shaking speed, contact time, initial solution pH, ionic strength, solution temperature, biosorbent dosage and initial dye concentration). Besides, the reusability of BABP for MB biosorption was also examined. Findings The biosorption results revealed that approximately 96% of MB was removed successfully at the optimized operational conditions. Pseudo-second-order and Langmuir models, respectively, better described the adsorption kinetics and isotherms. The monolayer biosorption capacity (qmax) for MB was about 97.09 mg/g. According to thermodynamics findings, the MB biosorption onto BABP is an exothermic and spontaneous process. The results demonstrate that BABP can be considered as potential eco-friendly, readily available and low-cost biosorbent for hazardous textile dyes removal from water bodies and also provides a promising method for minimization of agricultural solid wastes (e.g. plant barks). Originality/value The utilization of Balanites aegyptiaca bark powder (BABP), solid waste material, as low-cost and eco-friendly biosorbent for the removal of hazardous basic textile dye (methylene blue) from the aquatic environment.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Fanhua Wu ◽  
Yuyu Zhang ◽  
Tao Li ◽  
Yongfeng Liu ◽  
Yi Liu ◽  
...  

Purpose The purpose of this study was to prepare carboxylated attapulgite (APT-COOH) and then be used as one of the ligands to prepare metal organic framework (MOF) hybrid materials to reduce the cost of MOF materials and improve the dispersed condition of APT. And then the materials were used to enrich anionic dye Congo red from aqueous solution. Design/methodology/approach The MOF hybrid materials were designed by means of facile reflux method rather than hydrothermal method, characterized by Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) Spectrometer and pore structure. The dispersed degree of APT-COOH in the MOF materials was validated according to adsorption efficiency for Congo red. Findings Due to introduction of APT-COOH, the microenvironment of the MOF materials changed, leading to different adsorption behaviors. Compared to the MOF material without APT-COOH, the adsorption capacities of the hybridized MOF materials with different amounts of APT-COOH introduced increased by 4.58% and 15.55%, respectively, as the initial concentration of Congo red solution of 300 mg/L. Meantime, hybridized MOF materials were suitable to remove Congo red with low concentration, while the MOF material without APT-COOH was appropriate to enrich Congo red with high concentration. Research limitations/implications The microstructure of MOF hybrid materials in detail is the further and future investigation. Practical implications This study will provide a method to reduce the cost of MOF materials and a theoretical support to treat anionic dyes from aqueous solution. Originality/value APT-COOH was prepared and used as one of the ligands to synthesize MOF material to improve the dispersed degree of APT-COOH and reduce the cost of the MOF materials. The adsorption efficiency was greatly enhanced with low concentration of Congo red solution, and the results indicated that hydrogen bonding, electrostatic interaction, and p-p conjugation were involved in the adsorption process. The prepared MOFs materials exhibited excellent adsorption efficiency, which made the present materials highly promising and potentially useful in practical application as adsorbents to enrich anionic dyes such as Congo red from aqueous solution.


2017 ◽  
Vol 76 (10) ◽  
pp. 2719-2732 ◽  
Author(s):  
Nouf F. El-Harby ◽  
Shaimaa M. A. Ibrahim ◽  
Nadia A. Mohamed

Abstract Adsorption capacity of three antimicrobial terephthaloyl thiourea cross-linked chitosan hydrogels for Congo red dye removal from its aqueous solution has been investigated for the first time in this work. These hydrogels were prepared by reacting chitosan with various amounts of terephthaloyl diisothiocyanate cross-linker. The effect of the hydrogel structural variations and several dye adsorption processing parameters to achieve the best adsorption capacity were investigated. The hydrogels' structural variations were obtained by varying their terephthaloyl thiourea moieties content. The processing variables included initial concentration of the dye solution, temperature and time of exposure to the dye. The adsorption kinetics and isotherms showed that the sorption processes were better fitted by the pseudo-second-order equation and the Langmuir equation, respectively. On the basis of the Langmuir analysis Congo red dye gave the maximum sorption capacity of 44.248 mg/g. The results obtained confirmed that the sorption phenomena are most likely to be controlled by chemisorption process. The adsorption reaction was endothermic and spontaneous according to the calculated results of adsorption thermodynamics.


2021 ◽  
Vol 2063 (1) ◽  
pp. 012011
Author(s):  
Huda S Al-Niaeem ◽  
Ali A Abdulwahid ◽  
Whidad S Hanoosh

Abstract Hydrogels of acrylamide (AM), acrylamide\ 2-acrylamido-2-methyl-1-propane sulphonic acid (AMS), and acrylamide\ 2-acrylamido-2-methyl-1-propane sulphonic acid\graphene oxide (AMSGO) were prepared as adsorbents to remove carcinogenic dyes Congo red (CR) and Bismarck brown Y (BBY) from aqueous solutions. Hydrogels were characterized using FSEM and XRD analyses. For both dyes, the synthesized hydrogels demonstrated high adsorption capability at near-neutral pH. Experimental adsorption data were analyzed using the Langmuir and Freundlich isotherm models. It was found that the Langmuir model was more suitable for the experimental data. Kinetic studies found that the pseudo-second-order model demonstrated the best fitting to the experimental data. In addition, thermodynamic studies suggest that the adsorption process was spontaneous and endothermic. The prepared hydrogels were regenerated and reused in four consecutive cycles and it could be applied to remove anionic dyes from aqueous solutions as an effective adsorbent.


2018 ◽  
Vol 148 ◽  
pp. 601-607 ◽  
Author(s):  
Venkata Subbaiah Munagapati ◽  
Vijaya Yarramuthi ◽  
Yeji Kim ◽  
Kwon Min Lee ◽  
Dong-Su Kim

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 251
Author(s):  
Rohith K. Ramakrishnan ◽  
Vinod V. T. Padil ◽  
Stanisław Wacławek ◽  
Miroslav Černík ◽  
Rajender S. Varma

A novel, lightweight (8 mg/cm3), conjugate sponge of karaya gum (Kg) and chitosan (Ch) has been synthesized with very high porosity (~98%) and chemical stability, as a pH-responsive adsorbent material for the removal of anionic and cationic dyes from aqueous solutions. Experimental results showed that Kg-Ch conjugate sponge has good adsorption capacity for anionic dye methyl orange (MO: 32.81 mg/g) and cationic dye methylene blue (MB: 32.62 mg/g). The optimized Kg:Ch composition grants access to the free and pH-dependent ionizable functional groups on the surface of the sponge for the adsorption of dyes. The studies on the adsorption process as a function of pH, adsorbate concentration, adsorbent dose, and contact time indicated that the adsorption capacity of MB was decreased with increasing pH from 5 to 10 and external mass transfer together with intra-particle diffusion. The adsorption isotherm of the anionic dye MO was found to correlate with the Langmuir model (R2 = 0.99) while the adsorption of the cationic MB onto the sponge was better described by the Freundlich model (R2 = 0.99). Kinetic regression results specified that the adsorption kinetics were well represented by the pseudo-second-order model. The H-bonding, as well as electrostatic interaction between the polymers and the adsorption interactions of dyes onto Kg-Ch sponge from aqueous solutions, were investigated using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, and the highly wrinkled porous morphology was visualized in depth by field-emission scanning electron microscopy (FE-SEM) analysis. Moreover, the samples could be reused without loss of contaminant removal capacity over six successive adsorption-desorption cycles. The hierarchical three-dimensional sponge-like structure of Kg has not been reported yet and this novel Kg-Ch sponge functions as a promising candidate for the uninterrupted application of organic pollutant removal from water.


Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1437
Author(s):  
Chih Ming Ma ◽  
Bo-Yuan Yang ◽  
Gui-Bing Hong

Hydrogel beads based on the husk of agarwood fruit (HAF)/sodium alginate (SA), and based on the HAF/chitosan (CS) were developed for the removal of the dyes, crystal violet (CV) and reactive blue 4 (RB4), in aqueous solutions, respectively. The effects of the initial pH (2–10) of the dye solution, the adsorbent dosage (0.5–3.5 g/L), and contact time (0–540 min) were investigated in a batch system. The dynamic adsorption behavior of CV and RB4 can be represented well by the pseudo-second-order model and pseudo-first-order model, respectively. In addition, the adsorption isotherm data can be explained by the Langmuir isotherm model. Both hydrogel beads have acceptable adsorption selectivity and reusability for the study of selective adsorption and regeneration. Based on the effectiveness, selectivity, and reusability of these hydrogel beads, they can be treated as potential adsorbents for the removal of dyes in aqueous solutions.


2003 ◽  
Vol 38 (2) ◽  
pp. 393-411 ◽  
Author(s):  
Soufiane Tahiri ◽  
Ali Messaoudi ◽  
Abderrahman Albizane ◽  
Mohamed Azzi ◽  
Mohamed Bouhria ◽  
...  

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.


Sign in / Sign up

Export Citation Format

Share Document