High performance adsorption of hazardous triphenylmethane dye-crystal violet onto calcinated waste mussel shells

2019 ◽  
Vol 54 (3) ◽  
pp. 249-256 ◽  
Author(s):  
Sahra Dandil ◽  
Deniz Akin Sahbaz ◽  
Caglayan Acikgoz

Abstract Synthetic dyes are harmful to human beings, and the removal of colour from process or waste effluents is environmentally important. Crystal violet (CV) is a typical triphenylmethane dye, which is widely used in textile dyeing and paper printing industries. The present study shows that granulated and calcinated waste mussell shells (CWMS) can be used as a potential low-cost and locally available adsorbent for the removal of CV from aqueous solutions. The adsorption capacities of the CWMS for CV were investigated with respect to the effect of pH value, adsorbent dosage, contact time, initial dye concentration and temperature. Process variables were optimized, and a maximum dye adsorption of 482.0 mg/g was achieved at pH 6, 0.2 g/L adsorbent dosage, 220 min contact time and 25 °C for dye initial concentration of 100 mg/L. Adsorption kinetics and isotherms were followed by the pseudo-second order model and Freundlich isotherm models, respectively. Thermodynamic parameters demonstrated that adsorption of CV was spontaneous and endothermic in nature. The results indicated that the CWMS as a new adsorbent had the potential to serve in wastewater treatment applications, especially in the removal of CV from aqueous solutions.

2019 ◽  
Vol 6 (2) ◽  
pp. 66-74 ◽  
Author(s):  
Raziyeh Hosseini ◽  
Mohammad Hossein Sayadi ◽  
Hossein Shekari

The research was conducted with an aim to assess the efficiency of copper oxide nanoparticles as an adsorbent to remove Ni and Cr. The effect of pH, adsorbent dosage, contact time, initial concentration of metals (Ni and Cr) on the adsorption rate was evaluated and removal of these elements from aqueous solutions was measured using Atomic Absorption Spectrum System (Conter AA700). Moreover, the kinetic and isotherm besides thermodynamic adsorption models were assessed. The highest Ni and Cr removal rate occurred at an optimal pH of 7, and an initial concentration of 30 mg/L, a time period of 30 minutes, and 1 g/L of copper oxide nanoparticles. In fact, with the increase of adsorbent dosage and contact time, the removal efficiency increased and with initial concentration increase of Ni and Cr ions, the removal efficiency reduced. The correlation coefficient of isotherm models viz. Langmuir, Freundlich, Temkin, Redlich-Peterson, and Koble-Corrigan showed that Ni and Cr adsorption via copper oxide nanoparticles better follows the Langmuir model in relation to other models. The results showed that kinetic adsorption of Ni and Cr via copper oxide nanoparticles follows the second order pseudo model with correlation coefficients above 0.99. In addition, the achieved thermodynamic constants revealed that the adsorption process of metals (i.e., Ni and Cr) via copper oxide nanoparticles was endothermic and spontaneous and the reaction enthalpy values for these metals were 17.727 and 11.862 kJ/mol, respectively. In conclusion, copper oxide nanoparticles can be used as effective and environmentally compatible adsorbents to remove Ni and Cr ions from the aqueous solutions


2012 ◽  
Vol 09 (17) ◽  
pp. 48-59
Author(s):  
Carina Pitwak MAGDALENA ◽  
Denise Alves FUNGARO ◽  
Patricia CUNICO

Textile effluents, when not correctly treated, cause a high impact to the environment. The synthetic dyes are used in the fibber dying process, but part of them is discarded to receiving water body. The adsorption is a technique that has been used successfully for an effective removal of color. In this work, the adsorption of reactive dye Remazol Red RB from aqueous solution using zeolite of coal ash as low cost adsorbent was studied. The zeolite was synthesized by hydrothermal treatment with NaOH solution. The effect of experimental parameters such as contact time, pH, temperature and adding salt was investigated. The kinetics studies indicated that the adsorption followed the pseudo-second-order model with correlation coefficients > 0.99. The equilibrium was reached after 360 min of contact time. The experimental data were analyzed using Langmuir and Freundlich isotherm models and the data fitted well to the Langmuir isotherm. The maximum adsorption capacity of zeolite of coal ash for Remazol Vermelho RB was 1.20 mg g-1 with adsorption efficiency between 75 and 91%. The dye adsorption was more efficient in the presence of salts.


Author(s):  
A.M.M. Mawad ◽  
H. Albasri ◽  
H. A. Temerk

Contamination of water with Malachite green (MG) may threaten aquatic and human life. Nitrogen-fixing Azotobacter sp. is an efficient adsorbent for the removal of MG from dye solutions. The optimum pH for the biosorption process was determined. The maximum adsorption capacity and the effect of different adsorbate concentrations were detected. The kinetics and isotherm models for biosorption were constructed. Optimum adsorption of MG by Azotobacter sp. was obtained at pH 6.0, biomass concentration was 0.05%, initial dye concentration was 50 mg.L-1, and contact time was 600 mins. Dye adsorption exhibited an increase with contact time and initial malachite green concentration. The kinetics of the adsorption process was best followed by the pseudo-second-order kinetic model which confirms the chemisorption process. The adsorption equilibrium data fit well to the Langmuir model indicating a monolayer adsorption behavior onto a surface of Azotobacter sp. with a finite number of active sites. Maximum biosorption capacity was found to be 142.8 mg.g-1 of bacterial biomass. The dry biomass of Azotobacter sp. has proved to be an efficient biosorbent for the removal of synthetic dyes from actual industrial effluent that is contaminated with up to 400 mg.L-1 dye concentration.


Author(s):  
Hamed Biglari ◽  
Susana RodríguezíCouto ◽  
Yusef Omidi Khaniabadi ◽  
Heshmatollah Nourmoradi ◽  
Mohammad Khoshgoftar ◽  
...  

AbstractIn this study, the potential of hexadecyl trimethyl ammonium bromide modified montmorillonite (HDTMA-Mt) to remove the synthetic dyes Alizarin Red S (ARS) and Bromocresol Green (BCG) from aqueous media was assessed. The effect of different factors including surfactant loading rate onto the clay, contact time, pH, adsorbent dosage and dye concentrations, on the removal of ARS and BCG in batch systems were investigated. The adsorbent was characterized by means of scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometry (XRD). The equilibrium time for ARS and BCG was reached at 40 and 20 min, respectively, under optimized conditions (i.e. pH = 3, adsorbent dosage=1 g/L, surfactant loading rate onto the clay 70% of the cation exchange capacity (CEC) for ARS and 120% of the CEC for BCG, ARS concentration 50 mg/L and BCG concentration 500 mg/L). The adsorption rate of both dyes fitted the pseudo-second-order kinetic model and the equilibrium data was described by the Freundlich isotherm equation. The maximum monolayer adsorption capacities were equal to 666.6 and 1250 mg/g for ARS and BCG, respectively. Therefore, the HDTMA-Mt can be considered as an effective adsorbent for the removal of ARS and BCG from aqueous solutions.


2016 ◽  
Vol 74 (8) ◽  
pp. 1885-1898 ◽  
Author(s):  
M. Nageeb Rashed ◽  
M. A. El-Daim El Taher ◽  
Somaya M. M. Fadlalla

This study aims to explore the preparation and application of alum sludge (AS) and mud sludge (MS) from a drinking water treatment plant to remove methylene blue (MB) dye from aqueous solution. The sludge (MS and AS) was treated by chemical and physical activation to obtain new adsorbents. The adsorption experiments were carried out under different conditions of initial dye concentration (50–100 mg/L) adsorbent dosage (0.05–0.25 g), solution pH (3–9), temperature (20–60 °C) and contact time (20–90 min). Scanning electron microscopy (SEM) and X-ray diffraction instruments were used for characterization of the developed adsorbents. The results show that sludge activated by nitric acid (0.25 M HNO3) and pyrolysis at 700 °C were the best chemically and physically activated adsorbents. The optimum adsorption conditions for the adsorption of MB are 100 ppm initial dye concentration, 1 hour contact time, 250 °C solution temperature, pH 7 and 0.25 g adsorbent dosage. Application of the Langmuir and Freundlich Isotherm models showed that adsorbents fitted the Langmuir model well. SEM studies indicated the porous structural aspects of sludge suitable for removing MB dye.


2011 ◽  
Vol 322 ◽  
pp. 102-107
Author(s):  
Lu Hua You ◽  
Xin Tan ◽  
Qiong Qiong Liu ◽  
Lin Zhao

This article investigates the removal of ammonium from aqueous solutions using the ammonium ion-exchange material prepared by the modified kaolin. Batch tests were performed under a range of conditions to assess the effect of initial solution concentration, contact time and solution PH on the performance and capacity of the media for this application. The findings show that increasing initial solution concentration and contact time provide the best performance at an optimum PH of between 6 and 7 and the maximum ammonium adsorption capacity reaches at 79mgNH4+g-1 under the experimental conditions studied. Five isotherm models were used to describe the isotherm data. Three-parameter isotherm models (Redlich–Peterson and Langmuir–Freundlich) prove a better fit than two-parameter isotherm models (Langmuir, Freundlich and Temkin). These results indicate that the ammonium ion-exchange material is a promising material for cost-effective removal of ammonium from wastewater.


2020 ◽  
Vol 26 (2) ◽  
pp. 200127-0
Author(s):  
Min-Gyu Lee ◽  
Sang-Kyu Kam ◽  
Chang-Han Lee

The study focused on the removal of Sr and Cs ions in aqueous solutions by zeolitic materials synthesized from Jeju volcanic rocks using a fusion/hydrothermal method. The synthesis of the zeolitic materials was carried out using the fusion/hydrothermal method to reduce crystallization time. Morphological structures of the zeolitic materials could be confirmed to be the Na-A zeolite structure and crystalline with the chamfered-edged structure. In the adsorption experiment, as the initial concentrations of the Sr and Cs ions increased, it took longer to reach adsorption equilibrium. The adsorption kinetics and isotherms of Sr and Cs ions were predicted well by the pseudo-2nd-order and Langmuir isotherm models, respectively. The maximum adsorption capacities of Sr and Cs ions by the Langmuir isotherm model were 154.8 mg/g and 144.0 mg/g, respectively. The zeolitic materials prepared in this study is considered as an effective adsorbent for removing Sr and Cs ions in aqueous solutions.


2018 ◽  
Vol 18 (4) ◽  
pp. 724
Author(s):  
Rahmah Hashim Abdullah ◽  
Amjed Mirza Oda ◽  
Alaa Rasheed Omran ◽  
Ameer Salem Mottaleb ◽  
Teeba Mudhefer Mubarakah

The performance sawdust as a low cost adsorbent to remove Direct Blue 85 (DB85) dye from aqueous solutions has been evaluated. The characteristic of sawdust analyzed by FTIR and XRD. The removal percentage of this dye was studied at different experimental conditions such as contact time, adsorbent dosage, particle size, temperature, and pH. The optimum removal percentage value was found at pH 2.Temperature also has a positive impact on adsorption, where the adsorption of this dye on the sawdust increased as the temperature increased. High values of correlation coefficient signified that the adsorption of (DB85) dye on the surface of sawdust obey Langmuir and Freundlich adsorption isotherms.


Author(s):  
M. Ait Haki ◽  
A. Imgharn ◽  
N. Aarab ◽  
A. Hsini ◽  
A. Essekri ◽  
...  

Abstract The main objective of this study is to optimize a new composite for the depollution of contaminated water. The sodium hydroxide-modified Avocado shells (NaOH-AS) were firstly prepared, characterized by field-emission-scanning-electron-microscopy (FE-SEM), X-ray energy dispersive spectroscopy (EDS) and Fourier transforms infrared (FT-IR) spectroscopy, and applied for efficient removal of Crystal violet dye (CV) in wastewater. In addition, the adsorption in a batch system of CV dye on the NaOH-AS material was studied. Therefore, we accomplished a parametric study of the adsorption by studying the effect of several important parameters on the decolorizing power of the used material, namely, initial pH, contact time, initial CV dye concentration, temperature, and the ionic strength effect on the CV dye adsorption process were systematically assessed. The highest adsorption efficiency of CV dye (>96.9%) by NaOH-AS was obtained at pH >8. The pseudo-second-order kinetic model gave the best description of the adsorption kinetic of CV dye on the AS and NaOH-AS adsorbents. Besides, the mass transfer of CV dye molecules from the solution to the adsorbent surface occurred in three sequential stages (boundary layer diffusion, intraparticle diffusion and adsorption equilibrium). The adsorption isotherm data were best fitted with the Freundlich model. The adsorption capacity of AS increased from 135.88 to 179.80 mg g−1 after treatment by 1 M NaOH. The thermodynamic study showed that CV dye adsorption onto NaOH-AS was an exothermic and feasible process. The electrostatic interactions acted as the only forces governing the CV adsorption mechanism. The NaOH-AS demonstrated a satisfactory reusability. Therefore, we can state that the as-developed NaOH-AS material has a potential application prospect as an efficient adsorbent for CV dye from wastewaters.


2018 ◽  
Vol 18 (44) ◽  
pp. 5-11 ◽  
Author(s):  
Nizamettin Demirkıran ◽  
G D Turhan Özdemir ◽  
M Saraç ◽  
M Dardağan

In this study, the adsorption of methylene blue dye was examined by using pyrolusite ore as a low-cost alternative adsorbent source. Pyrolusite, which contains mainly MnO2, is a manganese ore. The effects of the initial concentration of dye, contact time, initial pH of solution, adsorbent dosage, stirring speed of solution, and average particle size of adsorbent on the adsorption of methylene blue were studied. It was found that the percentage of the adsorbed dye increased with increasing the amount of pyrolusite. While the initial dye concentration, initial pH, contact time, stirring speed, particle size, and adsorbent dosage were 25 ppm, 6, 90 min, 250 rpm, 63 µm, and 12 g/l, respectively, the efficiency of dye adsorption on pyrolusite ore was 99%. The isotherm and kinetic studies relating to this adsorption process were also made. It was found that the equilibrium data followed the Langmuir isotherm model while the kinetic of process could be described by the pseudo-second order kinetic model.


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