scholarly journals Nano-zeolite-graphene oxide composite for calcium hardness removal: isotherm and kinetic study

2020 ◽  
Vol 15 (4) ◽  
pp. 1011-1031
Author(s):  
Ram Ashok Konale ◽  
Nilesh Keshavrao Mahale ◽  
Sopan Tukaram Ingle
Keyword(s):  
Experimental Data ◽  
Graphene Oxide ◽  
Ultrasonic Method ◽  
Chemical Characterization ◽  
Intraparticle Diffusion ◽  
Second Order ◽  
X Rays ◽  
Pseudo Second Order ◽  
Hardness Removal ◽  
Adsorbent Dose

Abstract The present study is an attempt to synthesize and explore the applications of the synthetic nano-zeolites (nZ) and its composites with graphene oxide (GO) for water purification. The modified Hummer's method and hydrothermal methods were applied for the synthesis of the graphene oxide and nano zeolites respectively, followed by the preparation of the composite with the ultrasonic method. Scanning electron microscopy, energy dispersive analysis of X-rays, Fourier transform infrared spectroscopy and X-ray fluorescence were used for physico-chemical characterization of the composite. The various parameters of adsorbent dose, contact time, initial and final pH of solution were optimized for the removal of calcium hardness. The results indicate optimum removal (98%) can be reached at pH 7 while the removal is highly adsorbent dose-dependent. The nZGO removal data were investigated by pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion. In that, pseudo-second-order and intraparticle diffusion models are best fitted to the experimental data. The experimental data were also analysed by Langmuir, Freundlich and Temkin isotherms, the experimental data follows the Langmuir isotherm and the determination coefficient is 0.99.

Experimental Investigation on Adsorptive Removal of Phenolic Compounds from Aqueous Solution by Cr-Bentonite

2010 ◽  
Vol 160-162 ◽  
pp. 163-170
Author(s):  
Hong Zheng ◽  
Yang Wang ◽  
Peng Liang ◽  
Hong Bin Qi
Keyword(s):  
Experimental Data ◽  
Aqueous Solution ◽  
Phenolic Compounds ◽  
Intraparticle Diffusion ◽  
Second Order ◽  
Synthetic Wastewater ◽  
Order Kinetic ◽  
Sorption Data ◽  
Adsorptive Removal ◽  
Pseudo Second Order

The ability of Cr-bentonite prepared using synthetic wastewater containing chromium was investigated for adsorptive removal of 4-aminophenol and 4-chlorophenol from aqueous solution in a batch system at 25 °C. The physic-chemical parameters including pH value of solution and contact time were studied. The experimental data were analyzed by the Langmuir, Freundlich and Temkin models of sorption. The equilibrium sorption data for 4-aminophenol and 4-chlorophenol were well fitted to Langmuir adsorption isotherm and the monolayer sorption capacity was found to be 26.53 and 23.81 mg/g at 25 °C, respectively. The sorption energy calculated from Dubinin-Redushkevich (D-R) isotherm are 8.31 and 8.20 kJ/mol for the uptake of 4-aminophenol and 4-chlorophenol respectively which indicates that both the sorption processes are chemical in nature. The kinetic data were analyzed using pseudo-first order, pseudo-second order kinetic equation and intraparticle diffusion model. The experimental data fit very well the pseudo-second order kinetic model. Intraparticle diffusion affects 4-aminophenol and 4-chlorophenol uptake. Sorption studies carried out using industrial wastewater samples containing phenolic compounds show that there is significant potential for Cr-bentonite as an adsorbent material for phenollic compounds removal from aqueous solutions.

Equilibrium and Kinetic Modelling of Astrazon Yellow Adsorption by Sawdust: Effect of Important Parameters

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Naima Ouazene ◽  
Mohamed Nasser Sahmoune
Keyword(s):  
Particle Size ◽  
Contact Time ◽  
Low Cost ◽  
Intraparticle Diffusion ◽  
Second Order ◽  
Aleppo Pine ◽  
Pine Tree ◽  
Equilibrium Data ◽  
Pseudo Second Order ◽  
Adsorbent Dose

This paper aims to investigate the sorption of Astrazon yellow (A.Y.) onto sawdust (Aleppo pine tree), a forest waste as that acts as a low-cost adsorbent. In our experiments, the batch sorption is studied with respect to solute concentration, contact time, adsorbent dose, particle size and pH. The adsorption process attains equilibrium within 300 minutes. The extent of dye removal decreased with increasing particle size and increased with increasing contact time, adsorbent dose and pH. The equilibrium data were analysed by the Langmuir and Freundlich isotherms. The characteristic parameters for each isotherm were determined. By considering the experimental results and adsorption models applied in this study, it can be concluded that equilibrium data were represented well by the Langmuir isotherm equation. Maximum adsorption capacity calculated at 293K was 81.8 mg/g. Five kinetic models (pseudo-first order, pseudo-second order, fractional power, Elovich and intraparticle diffusion kinetic equations) were used to predict the adsorption rate constants. The kinetics of adsorption of the basic dye followed both Elovich and pseudo-second order kinetics, and intraparticle diffusion was not the sole rate-controlling step. The effective diffusion of Astrazon yellow in sawdust according to Boyd Model was 24.22 .10-12 m2/S. In order to reveal the adsorption characteristic of sawdust samples, SEM and FTIR spectra analyses were carried out. The results show that sawdust (Aleppo pine tree) can be an alternative low-cost adsorbent for removing cationic dyes from wastewater.

scholarly journals Statistical Optimization and Modeling of Methylene Blue Adsorption Onto Graphene Oxide in Batch and Fixed-Bed Column

2018 ◽  
Vol 5 (1) ◽  
pp. 21-34
Author(s):  
Habib Koolivand ◽  
Afsaneh Shahbazi
Keyword(s):  
Experimental Data ◽  
Methylene Blue ◽  
Graphene Oxide ◽  
Fixed Bed ◽  
Second Order ◽  
Batch Adsorption ◽  
Fixed Bed Column ◽  
Column Adsorption ◽  
Pseudo Second Order ◽  
Real Wastewater

The batch and fixed-bed column adsorption of methylene blue (MB), a widely used toxic dye, onto graphene oxide (GO) was investigated in this study. GO was synthesized using modified Hummers method and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Response surface methodology (RSM) was employed to optimize batch and fixed-bed column adsorption of MB. Batch adsorption experiments were carried out by central composite design (CCD) with three input parameters including initial MB concentration (C0: 50-350 mg/L), GO dosage (D: 0.05-0.7 g/L), and pH (pH: 3-9). The adsorption capacity of GO for MB removal in the optimum level of factors (C0: 50 mg/L, D: 0.05 g/L, and pH: 8.5) was predicted by the model to be 700 mg/g. Adsorption kinetic data were tested using pseudo-first order, pseudo-second order, and intraparticle diffusion models. The kinetic experimental data was well fitted with pseudo-second order kinetic model (R2=1). The adsorption of MB onto GO demonstrated that Langmuir model (R2=0.999) could better fit the adsorption data than the Freundlich model (R2=0.914). Thermodynamic parameters including enthalpy (ΔH), Gibbs free energy (ΔG), and entropy (ΔS) were also investigated. Positive value of ΔH and negative value of ΔG indicated the endothermic and spontaneous nature of the adsorption. The positive value of ΔS also showed increased randomness at the solid/liquid interface during the adsorption of MB onto GO. The real wastewater experiment at optimum conditions showed high performance of adsorbent in the presence of other ions. Fixed-bed column experiments were designed using a three-factor, three-level Box-Behnken design (BBD) to investigate the single and combined effects of influent concentration (Cinf: 50-200 mg/L), flow rate (Q: 0.25-0.8 mL/min), and bed height (BH: 3-7 cm). MB removal from GO in the optimum levels of factors (Cinf: 51 mg/L, BH: 5.7 cm, and Q: 0.25 mL/min) was predicted by the model to be 86% (qe=459.3 mg/g). Fixed-bed experimental data were also fitted well to the Thomas and BDST models. The results showed that GO can be used as an efficient adsorbent for batch and fixed-bed adsorption of cationic dyes from synthetic and real wastewater.

scholarly journals Harnessing of Newly Tailored Poly (Acrylonitrile)-Starch Nanoparticle Graft Copolymer for Copper Ion Removal via Oximation Reaction

2021 ◽  
Author(s):  
khaled Mostafa ◽  
H. Ameen ◽  
A. Ebessy ◽  
A. El-Sanabary
Keyword(s):  
Experimental Data ◽  
Adsorption Capacity ◽  
Graft Copolymer ◽  
Adsorption Kinetics ◽  
Copper Ions ◽  
Copper Ion ◽  
Second Order ◽  
First Order ◽  
Pseudo Second Order ◽  
Pseudo First Order

Abstract Our recently tailored and fully characterized poly (AN)-starch nanoparticle graft copolymer having 60.1 G.Y. % was used as a starting substrate for copper ions removal from waste water effluent after chemical modification with hydroxyl amine via oximation reaction. This was done to change the abundant nitrile groups in the above copolymer into amidoxime one and the resultant poly (amidoxime) resin was used as adsorbent for copper ions. The resin was characterized qualitatively via rapid vanadium ion test and instrumentally by FT-IR spectra and SEM morphological analysis to confirm the presence of amidoxime groups. The adsorption capacity of the resin was done using the batch technique, whereas the residual copper ions content in the filtrate before and after adsorption was measured using atomic adsorption spectrometry. It was found that the maximum adsorption capacity of poly (amidoxime) resin was 115.2 mg/g at pH 7, 400ppm copper ions concentration and 0.25 g adsorbent at room temperature. The adsorption, kinetics and isothermal study of the process is scrutinized using different variables, such as pH, contact time, copper ion concentration and adsorbent dosage. Different kinetics models comprising the pseudo-first-order and pseudo-second-order have been applied to the experimental data to envisage the adsorption kinetics. It was found from kinetic study that pseudo-second-order rate equation was better than pseudo-first-order supporting the formation of chemisorption process. While, in case of isothermal study, the examination of calculated correlation coefficient (R2) values showed that the Langmuir model provide the best fit to experimental data than Freundlich one.

scholarly journals Dye removal abilities of the mesophilic and thermophilic biomass: a kinetics study

2018 ◽  
Vol 20 (2) ◽  
pp. 408-416
Keyword(s):  
Intraparticle Diffusion ◽  
Second Order ◽  
Intraparticle Diffusion Model ◽  
First Order Kinetics ◽  
Different Types ◽  
Pseudo Second Order ◽  
Acidic Conditions ◽  
Red Dye ◽  
Experimental Kinetics ◽  
Kinetics Of

Mesophilic biomass and thermophilic biomass samples were isolated and used to remove Dorasyn Red dye from aqueous solutions. The biosorption kinetics of dye uptake by four different types of biomass at three temperatures (20, 30, and 40 °C) were investigated using pseudo-first order kinetics, pseudo-second order kinetics, intraparticle diffusion, Elovich, and Bangham models. The pseudo-second-order kinetics model and the first stage of the intraparticle diffusion model were effective in describing the experimental kinetics data. The biosorption results showed that the mesophilic biomass samples could be useful for removing dye under acidic conditions.

Kinetics of Glyphosate Adsorption on Composite Resin from Aqueous Solution

2013 ◽  
Vol 803 ◽  
pp. 157-160
Author(s):  
Zhen Zhen Kong ◽  
Dong Mei Jia ◽  
Su Wen Cui
Keyword(s):  
Experimental Data ◽  
Aqueous Solution ◽  
Composite Resin ◽  
Order Equation ◽  
Second Order ◽  
First Order ◽  
Basic Resin ◽  
Pseudo Second Order ◽  
Kinetics Of ◽  
Best Fit

The composite weakly basic resin (D301Fe) was prepared and examined using scanning electron microscopy and Fourier transform infrared spectroscopy. The adsorption kinetics of glyphosate from aqueous solution onto composite weakly basic resin (D301Fe) were investigated under different conditions. The experimental data was analyzed using various adsorption kinetic models like pseudo-first order, the pseudo-second order, the Elovich and the parabolic diffusion models to determine the best-fit equation for the adsorption of glyphosate onto D301Fe. The results show that the pseudo-second order equation fitted the experimental data well and its adsorption was chemisorption-controlled.

scholarly journals Removal of Malachite Green from Aqueous Solution by Activated Carbon Developed from Cocoa (Theobroma Cacao) Shell - A Kinetic and Equilibrium Studies

2011 ◽  
Vol 8 (s1) ◽  
pp. S363-S371 ◽  
Author(s):  
C. Theivarasu ◽  
S. Mylsamy
Keyword(s):  
Experimental Data ◽  
Activated Carbon ◽  
Malachite Green ◽  
Kinetic Models ◽  
Theobroma Cacao ◽  
Second Order ◽  
Order Kinetic ◽  
Equilibrium Studies ◽  
Initial Ph ◽  
Pseudo Second Order

The removal of malachite green (MG) by cocoa (Theobroma cacao) shell activated carbon (CSAC) was investigated in present study. Adsorption studies were performed by batch experiments as a function of process parameters such as initial pH, contact time, initial concentration and adsorbent dose. A comparison of kinetic models applied to the adsorption of MG on CSAC was evaluated for the pseudo-first order and pseudo-second order kinetic models. Results showed that the pseudo-second order kinetic model was found to correlate the experimental data well. The experimental equilibrium adsorption data was represented with Langmuir, Freundlich, Tempkin, Dubinin-Radushkevich and Flory-Huggins isotherms. The experimental data obtained in the present study indicated that activated carbon developed from cocoa shell can be attractive options for dye removal from waste water.

scholarly journals Modelling of lead removal by an aquatic moss

2011 ◽  
Vol 63 (1) ◽  
pp. 136-142 ◽  
Author(s):  
R. J. E. Martins ◽  
R. A. R. Boaventura
Keyword(s):  
Experimental Data ◽  
Metal Concentration ◽  
Sorption Capacity ◽  
Metal Ion ◽  
Second Order ◽  
Lead Removal ◽  
Present System ◽  
Fontinalis Antipyretica ◽  
Aquatic Moss ◽  
Pseudo Second Order

Aquatic bryophytes are frequently used as biomonitors for trace metals in aquatic ecosystems. Nevertheless, their special characteristics also allow using them as biosorbents to clean industrial wastewaters. As biosorption is a low cost and effective method for treating metal-bearing wastewaters, understanding the process kinetics is relevant for design purposes. In this study, the ability of the aquatic bryophyte Fontinalis antipyretica to remove lead from simulated wastewaters was evaluated. Three kinetic models (pseudo-first order, pseudo-second order and Elovich) were fitted to the experimental data and compared by the F-test. Previously, the effect on biosorption of parameters such as the initial solution pH, contact time and initial metal ion concentration was investigated. The initial pH of the solution was found to have an optimum value is in the range 4.0–6.0. The equilibrium sorption capacity of lead by Fontinalis antipyretica increased with the initial metal concentration. For an initial metal concentration of 10 mg L−1, the uptake capacity at equilibrium was 4.8 mg g−1. Nevertheless, when the initial concentration increased up to 100 mg L−1, the uptake of lead was 10 times higher. The pseudo-second order biosorption kinetic model provided the better correlation with the experimental data (R2=1.00). The applicability of the Langmuir and Freundlich adsorption isotherms to the present system was also assessed. The maximum lead sorption capacity by Fontinalis antipyretica was 68 mg g−1.

scholarly journals Simultaneous Removal of Lead and Nickel Ions from Aqueous Synthetic Solutions by Chitosan Coated Cobalt Ferrite

2017 ◽  
Vol 68 (1) ◽  
pp. 1-5
Author(s):  
Rodica Elena Patescu ◽  
Claudia Maria Simonescu ◽  
Cristian Onose ◽  
Teodor Laurentiu Busuioc ◽  
Daiana Elena Pasarica ◽  
...  
Keyword(s):  
Experimental Data ◽  
Aqueous Solutions ◽  
Sorption Capacity ◽  
Cobalt Ferrite ◽  
Second Order ◽  
Simultaneous Removal ◽  
Order Model ◽  
Diffusion Kinetic ◽  
Nickel Ions ◽  
Pseudo Second Order

This research study deals with lead and nickel simultaneous removal from aqueous solutions by the use of chitosan coated cobalt ferrite as adsorbent. Batch removal tests were performed in order to establish the main parameters that influence the sorption capacity, removal efficiency and the selectivity of this adsorbent. The values of sorption capacity for lead and nickel experimentally determined are: 56.23 mg/g and respectively 45.11 mg/g. Langmuir and Freundlich adsorption isotherms were used to interpret the sorption experimental data. The kinetic data were explored by pseudo-first order, pseudo-second order and intraparticle diffusion kinetic models. The experimental data were well fitted with the pseudo-second order model for both heavy metals. The main conclusion that can be drawn from this research is that this material can be successfully used for the removal of lead and nickel from binary aqueous solutions and wastewater.

scholarly journals Prediction of adsorption efficiency for the removal malachite green and acid blue 161 dyes by marble sludge dust using ANN

2014 ◽  
Vol 16 (4) ◽  
pp. 676-689 ◽  
Keyword(s):  
Experimental Data ◽  
Malachite Green ◽  
Second Order ◽  
Isotherm Models ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Ann Model ◽  
Marble Dust ◽  
Pseudo Second Order ◽  
Acid Blue

<div> <p>In the present study, batch adsorption studies were performed for the removal of malachite green and acid blue 161 dyes from aqueous solutions by varying parameters such as contact time, waste marble dust amount, initial dye concentration and temperature. The equilibrium adsorption data were analyzed by Langmuir, Freundlich and Temkin adsorption isotherm models. The Langmuir and Freundlich adsorption models agree well with experimental data. The pseudo-second order, intraparticle intraparticle diffusion and Elovich kinetic models were applied to the experimental data in order to describe the removal mechanism of dye ions by waste marble dust. The pseudo-second order kinetic was the best fit kinetic model for the experimental data. Thermodynamics parameters such as Δ<em>G</em>, Δ<em>H</em> and Δ<em>S </em>were also calculated for the adsorption processes. The experimental data were used to construct an artificial neural network (ANN) model to predict removal of malachite green and acid blue 161 dyes by waste marble dust. A three-layer ANN, an input layer with four neurons, a hidden layer with 12 neurons, and an output layer with one neuron is constructed. Different training algorithms were tested on the model to obtain the proper weights and bias values for ANN model. The results show that waste marble dust is an efficient sorbent for malachite green dye and ANN network, which is easy to implement and is able to model the batch experimental system.</p> </div> <p>&nbsp;</p>

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