Enhanced adsorption of cationic and anionic dyes from aqueous solutions by polyacid doped polyaniline

2018 ◽  
Vol 245 ◽  
pp. 151-159 ◽  
Author(s):  
Junjie Shen ◽  
Salman Shahid ◽  
Ida Amura ◽  
Adem Sarihan ◽  
Mi Tian ◽  
...  
Polymers ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1136 ◽  
Author(s):  
Qiang Li ◽  
Fei Pan ◽  
Wentao Li ◽  
Dongya Li ◽  
Haiming Xu ◽  
...  

In this study, a novel 2-vinylpyridine functionalized magnetic nanoparticle (Mag-PVP) was successfully prepared. The prepared Mag-PVP was characterized by transmission electronic microscopy (TEM), Fourier transform infrared spectrophotometry (FT-IR), vibrating sample magnetometry (VSM) and thermogravimetric analysis (TGA), and was used for the adsorption of bisphenol A (BPA) from aqueous solutions. Mag-PVP, which is composed of Fe3O4 nanoparticles and poly divinylbenzene-2-vinylpyridine (with a thickness of 10 nm), exhibited magnetic properties (Ms = 44.6 emu/g) and thermal stability. The maximum adsorption capacity (Qm) of Mag-PVP for BPA obtained from the Langmuir isotherm was 115.87 mg/g at 20 °C, which was more than that of Fe3O4 nanospheres. In the presence of NaCl, the improved adsorption capacity of Mag-PVP was probably attributed to the screening effect of Mag-PVP surface charge and salting-out effect. In the presence of CaCl2 and humic acid (HA), the adsorption capacity of BPA decreased due to competitive adsorption. The adsorption of BPA by Mag-PVP increased slightly with the increase in pH from 3.0 to 5.0 and obtained the largest adsorption amount at pH 5.0, which was probably attributed to hydrogen bonding interactions. Moreover, in actual water, Mag-PVP still showed excellent adsorption performance in removing BPA. The high adsorption capacity and excellent reusability performance in this work indicated that Mag-PVP was an effective adsorbent for removing BPA from aqueous solutions.


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.


2021 ◽  
Author(s):  
G. Pascual ◽  
M. Riba-Moliner ◽  
J. M. Canal ◽  
J. Garcia-Raurich

Abstract Physically and chemically modified orange and lemon mesocarps are used as natural adsorbents for both cationic and anionic dyes from wastewaters of textile dyeing industry. Adsorptivity of the orange-based and lemon-based adsorbents to the dyes are studied simulating a batch and a continuous industrial process. Thus, the most suitable operating conditions to achieve the maximum adsorption yield are provided. Results demonstrate that treated orange and lemon mesocarps can be used as excellent reusable adsorbents to the removal of cationic and anionic dyes from aqueous solutions. Moreover, the recovery of the adsorbed dye is also reliable and proved.


2019 ◽  
Vol 31 (8) ◽  
pp. 1675-1682 ◽  
Author(s):  
D.O. Sulistiono ◽  
E. Santoso ◽  
R. Ediati

Impregnation of mesoporous silica MCM-41 on metal organic framework type HKUST-1 or often called CuBTC (BTC = 1,3,5-benzenetricarboxylate) has been successfully carried out by solvothermal methods in a solvent mixture of water, ethanol and N,N-dimethylformamide (DMF). The XRD patterns of the obtained solids showed that MCM-41/HKUST-1 composites had the same crystalline phase as pure as HKUST-1. SEM images revealed that the impregnation of the mesoporous silica to HKUST-1 did not alter the surface morphology of the original HKUST-1, which had octahedral shapes. In addition, the thermal stability of the MCM-41/HKUST-1 composites reached 302 °C, increased by 292 °C in comparison to the HKUST-1, even though the impregnation process resulted in a decreased in the specific surface area of the composites. Furthermore, MCM-41/HKUST-1 composites showed outstanding performance as adsorbent of methylene blue and Congo red in aqueous solutions. Results of adsorption studies showed that a pseudo-second order kinetics and Langmuir isotherm were observed for both types of dyes.


2018 ◽  
Vol 3 (1) ◽  
pp. 4 ◽  
Author(s):  
Liudmyla Soldatkina ◽  
Marianna Zavrichko

Corn stalks (CS) were modified by a cationic surfactant, cetylpyridinium bromide (CPB), and used as an adsorbent (CS-CP) to remove anionic dyes [Acid Red (AR) and Acid Orange (AO)] from aqueous solutions. The FTIR analysis and the obtained calculations based on the determination of the adsorption capacity of CS towards CPB confirmed that the cationic surfactant had been adsorbed on the surface of corn stalks. Adsorption of the anionic dyes on modified corn stalks was investigated in a series of batch adsorption experiments at 303–328 K. The adsorption data were analyzed using Langmuir, Freundlich, and Temkin models. The Langmuir model was found to be more suitable for the experimental data of the anionic dyes on CS-CP than other adsorption models. Kinetic studies revealed that the pseudo-second order model showed the best fit to the experimental data. The thermodynamic parameters indicated that the adsorption process was spontaneous and exothermic. Mechanisms involving ion exchange and chemisorption might be responsible for the uptake of the anionic dyes on CS-CP. Obtained results imply that CS-CP could be applied as an effective adsorbent to remove anionic dyes from aqueous solutions.


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