Box–Behnken Design for Optimizing the Synthesis Condition and Adsorption Capability of Covalently Crosslinked Chitosan/coal Fly Ash Composite

2021 ◽  
Author(s):  
Ibrahim Awad Mohammed ◽  
Nurul Najwa Abd Malek ◽  
Ali H. Jawad ◽  
Mohd Sufri Mastuli ◽  
Zeid A. Al-Othman
Keyword(s):  
Fly Ash ◽  
Coal Fly Ash ◽  
Freundlich Isotherm ◽  
Polluted Water ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
Box Behnken Design ◽  
Crosslinked Chitosan ◽  
Adsorbent Dose

Abstract The growing concern regarding the environmental protection has encouraged researchers to focus their efforts on developing better and more effective possibilities of removing pollutants. In this research, a biocomposite adsorbent of covalently crosslinked chitosan-epichlorohydrin/coal fly ash (CHT-ECH/CFA) was synthesized and applied for reactive red 120 dye (RR120) removal. The CHT-ECH/CFA was characterized by BET, pH potentiometric, pHpzc, XRD, FTIR and SEM-EDX. Box–Behnken Design (BBD) was employed to assess the effects of the adsorption key parameters such as CFA loading into CTH-ECH matrix, adsorbent dose, solution pH, working temperature and contact time. The optimized CFA loading, adsorbent dose, temperature, time, and pH were observed to be 50 %, 0.07 g, 45 °C, 60 min, and pH 4 respectively. From BBD, the highest removal of RR120 removal at optimum conditions was found to be 90.2%. The results showed that adsorption performance can be modelled perfectly by both Langmuir and Freundlich isotherm models with maximum adsorption capacity of 237.7 mg/g at 45 °C. Moreover, the adsorption kinetics were well fitted to the pseudo-second order model. Based on the findings from the experiments conducted, the hybrid biocomposite adsorbent offers adequate potential for the treatment of anionic dye-polluted water.

scholarly journals Treatment of Sulphate Rich Process Effluents using Coal Fly Ash

2021 ◽  
Vol 241 ◽  
pp. 01002
Author(s):  
Tumeletso Lekgoba ◽  
Freeman Ntuli ◽  
Bernard Mosweu
Keyword(s):  
Fly Ash ◽  
Coal Fly Ash ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Local Power ◽  
Order Model ◽  
Solution Ph ◽  
Sorption Data ◽  
X Ray ◽  
Effective Removal

Coal fly ash obtained from a local power station was used as an adsorbent in the removal of sulphates in an aqueous solution. The coal fly ash was characterised using an x-ray fluorescence (XRF) which revealed that it was class C and sub-bituminous type fly ash, an x—ray diffractometer (XRD) which revealed the dominance of a large amorphous phase and a Fourier Transform Infrared Spectroscopy (FTIR) which showed the presence of both organic and inorganic functional groups. Adsorbent dosage, contact time, temperature and solution pH were varied and all the parameters showed a higher uptake of sulphate ions with their increase, except pH which showed a decreasing uptake. The pseudo second order model showed a better fit for the sorption data with lower error values than the pseudo first order model. The uptake of sulphate ions followed both the Langmuir and the Freundlich isotherm models with RL values for the Langmuir within the range 0 < RL < 1 and n-values for the Freundlich within the range 0 < n < 10 showing a favourable sorption for both models. All the thermodynamic parameters (ΔG°, ΔH° and ΔS°) were positive indicating a non – spontaneous, endothermic and a random solid – liquid interface. The process was shown to follow a unimolecular layer approach with chemical adsorption as the dominating mechanism. Generally, coal fly ash showed a higher affinity for sulphates leading to its effective removal.

scholarly journals LDH Nanocubes Synthesized with Zeolite Templates and Their High Performance as Adsorbents

Nanomaterials ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3315
Author(s):  
Moftah Essa Elkartehi ◽  
Rehab Mahmoud ◽  
Nabila Shehata ◽  
Ahmed Farghali ◽  
Shimaa Gamil ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Average Pore Size ◽  
Second Order ◽  
Polluted Water ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
Average Pore ◽  
X Ray ◽  
Pseudo Second Order

In this work, the efficiency of the adsorptive removal of the organic cationic dye methylene blue (MB) from polluted water was examined using three materials: natural clay (zeolite), Zn-Fe layered double hydroxide (LDH), and zeolite/LDH composite. These materials were characterized via X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray (EDX) diffraction (XRF), low-temperature N2 adsorption, pore volume and average pore size distribution and field emission scanning electron microscopy (FE-SEM). The properties of the applied nanomaterials regarding the adsorption of MB were investigated by determining various experimental parameters, such as the contact time, initial dye concentration, and solution pH. In addition, the adsorption isotherm model was estimated using the Langmuir, Freundlich, and Langmuir–Freundlich isotherm models. The Langmuir model was the best-fitting for all applied nanomaterials. In addition, the kinetics were analyzed by using pseudo-first-order, pseudo-second-order, and intraparticle diffusion models, and the pseudo-second-order model was an apparent fit for all three applied nanomaterials. The maximum Adsorption capacity toward MB obtained from the materials was in the order zeolite/LDH composite > zeolites > Zn-Fe LDH. Thus, the zeolite/LDH composite is an excellent adsorbent for the removal of MB from polluted water.

Adsorption of Cobalt Ions onto Mycobacterium phlei from Wastewaters

2011 ◽  
Vol 71-78 ◽  
pp. 2249-2252 ◽  
Author(s):  
Yan Xing
Keyword(s):  
Practical Implication ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Solution Ph ◽  
Cobalt Ions ◽  
Mycobacterium Phlei ◽  
Order Kinetic Model ◽  
Economic Technology

This fundamental work deals with the biosorption removal of Co(II) using a Mycobacterium phlei strain. Several variables that have an effect on the capacity of cobalt biosorption from aqueous solution by Mycobacterium phlei were studied. particularly the effects of solution pH, initial Co(II) concentration, contact time and biomass dose. The experimental data were modeled by Langmuir and Freundlich isotherm models. Langmuir model resulted in the best fit of the adsorption data. The maximum adsorption capacity for Co(II) was 68.22 mg/g. The best correlation was provided by the second-order kinetic model, implying that chemical sorption was the rate-limiting step. The practical implication of this study is the development of an effective and economic technology for Co(II) removal from wastewaters.

scholarly journals Activated carbon from mustard stalk biomass: Synthesis, characterization and application in wastewater treatment

2021 ◽  
pp. 10-10
Author(s):  
Kalpana Patidar ◽  
Manish Vashishtha
Keyword(s):  
Activated Carbon ◽  
Chemical Activation ◽  
Total Pore Volume ◽  
Freundlich Isotherm ◽  
Bet Surface Area ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
Isotherm Study ◽  
Adsorption Rates

Present work is focused on the preparation of mustard stalk activated carbon (MSAC) using chemical activation with H3PO4 and exploring its properties for its use in dye removal from wastewater. Adsorption variable (dosage, contact time, and solution pH), pore structure, morphology, surface functional groups, equilibrium kinetics, and isotherm study for removal of methylene blue (MB) using MSAC were investigated. The present study showed that an adsorption dosage of 0.2 g L-1 and pH 8 can be considered as optimum for the MB removal. SEM result showed that pore of MSAC was larger than the pore of the mustard stalk (MS). BET surface area and total pore volume of MSAC were found as 510 m2 g-1 and 0.33 cm3 g-1, respectively. Equilibrium adsorption data were examined by Langmuir and Freundlich isotherm models. Better correspondence to the Langmuir model with a maximum adsorption capacity of 212.76 mg g-1 (MB onto MSAC) was obtained. Dimensionless factor, RL revealed favourable nature of the sorption in the MSAC - MB system. Adsorption rates were found to conform to the pseudo-second-order kinetics with good correlation. These results show that the MSAC could be used as a renewable and economical alternative to commercial AC in the removal of MB dye from wastewater.

scholarly journals Adsorptive Removal of Malachite Green Dye onto Coal-Associated Soil and Conditions Optimization

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
T. R. Sundararaman ◽  
A. Saravanan ◽  
P. Senthil Kumar ◽  
M. Millicent Mabel ◽  
R. V. Hemavathy ◽  
...  
Keyword(s):  
Malachite Green ◽  
Nonlinear Models ◽  
Water Environment ◽  
Dye Adsorption ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
Best Fit

The present research was investigated to eliminate the cationic dye (malachite green (MG)) from the water environment using coal-associated soil. The adsorbent material was characterized using scanning electron microscopy (SEM) and Fourier Transform Infrared Spectrophotometer (FTIR) analyses. Batch experiments were performed to investigate the different factors which affect the adsorption study. The maximum percentage removal of MG dye was attained as follows: adsorbent dose of 1.0 g/L (0.2 to 1.6 g/L), solution pH of 6.0 (2.0 to 9.0), temperature of 30°C (30 to 60°C), time contact of 60min (10 to 90 min), and dye’s concentration of 25 mg/L (25 to 150 mg/L). The adsorption isotherm was studied with four different isotherm models and results showed that the Freundlich isotherm model gave the best fit than the other nonlinear models to designate the isotherm behaviours with R 2 value of 0.9568, and the maximum adsorption capacity of coal-associated soil for MG dye adsorption is 89.97 mg/g. The evaluation of kinetic studies was performed by using three different kinetic models, where it exposed that pseudofirst order providing the best fit with R 2 value of 0.96 (25 to 150 mg/L). The thermodynamic parameters Gibbs free energy (ΔG°), entropy (ΔS°), and enthalpy (ΔH°) were endorsing that the present adsorption system was exothermic. Thus, the experimental results state that coal-associated soil could be an alternative material for the exclusion of dyes from water.

Adsorption Properties of Dye onto Mg/Al-CO3 Layered Double Hydroxide

2012 ◽  
Vol 455-456 ◽  
pp. 677-682
Author(s):  
Li Fang Zhang ◽  
De Zhou Wei
Keyword(s):  
Layered Double Hydroxide ◽  
Dye Removal ◽  
Adsorption Equilibrium ◽  
Freundlich Isotherm ◽  
Molar Ratio ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
Initial Ph ◽  
Double Hydroxide

Adsorption of reactive red on Mg/Al-CO3 layered double hydroxide in a batch stirred system was investigated. Experiments were carried out as function of Mg/Al molar ratio, contact time, initial pH, adsorbent amount and temperature. It was found that the maximum dye removal was at Mg/Al molar ratio of 3. Solution pH ranging from 2-8 had little effect on adsorption rate. Dye removal decreased with increased temperature in studied temperature range. The Langmuir and Freundlich isotherm models were used for modeling the adsorption equilibrium. The adsorption equilibrium data could well interpreted by the Langmuir models with maximum adsorption capacity of 131.58 mg/g (R2=0.9986). The results indicate the possible dye removal from water by using Mg/Al-CO3 layered double hydroxide.

scholarly journals Batch equilibrium and kinetics of mercury removal from aqueous solutions using polythiophene/graphene oxide nanocomposite

2017 ◽  
Vol 75 (12) ◽  
pp. 2841-2851 ◽  
Author(s):  
Anthony M. Muliwa ◽  
Maurice S. Onyango ◽  
Arjun Maity ◽  
Aoyi Ochieng
Keyword(s):  
Graphene Oxide ◽  
Aqueous Solutions ◽  
Freundlich Isotherm ◽  
Significant Loss ◽  
Mercury Removal ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
Equilibrium Studies ◽  
Mercury Uptake

Polythiophene/graphene oxide (PTh/GO) nanocomposite (NC) was prepared through polymerisation of thiophene in the presence of GO and was used for mercury ions (Hg2+) adsorption in aqueous solutions. Equilibrium studies showed that mercury removal was strongly influenced by solution pH and GO composition in the NC. The equilibrium data were well described by both Langmuir and Freundlich isotherm models, with a Langmuir maximum adsorption capacity of 113.6 mg/g. Adsorption kinetics were rapid and correlated well with the pseudo-second-order model. The thermodynamic studies indicated that the adsorption was spontaneous and endothermic in nature, and occurred through a physicochemical mechanism. Desorption studies revealed that PTh/GO NC could be used repeatedly for three adsorption-desorption cycles without a significant loss in its capacity. Competing ions reduced mercury uptake although considerable values were still attained. The findings of this study suggest that PTh/GO NC is a potential adsorbent for Hg2+ removal from aqueous solutions.

scholarly journals Fly Ash Coated with Magnetic Materials: Improved Adsorbent for Cu (II) Removal from Wastewater

Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 63
Author(s):  
Maria Harja ◽  
Gabriela Buema ◽  
Nicoleta Lupu ◽  
Horia Chiriac ◽  
Dumitru Daniel Herea ◽  
...  
Keyword(s):  
Fly Ash ◽  
Adsorption Capacity ◽  
Copper Ions ◽  
Synthetic Wastewater ◽  
Bet Surface Area ◽  
Isotherm Models ◽  
Batch Adsorption ◽  
Maximum Adsorption Capacity ◽  
Copper Adsorption ◽  
X Ray

Fly ash/magnetite material was used for the adsorption of copper ions from synthetic wastewater. The obtained material was characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) surface area, and vibrating sample magnetometer (VSM). Batch adsorption experiments were employed in order to investigate the effects of adsorbent dose, initial Cu (II) concentration and contact time over adsorption efficiency. The experimental isotherms were modeled using Langmuir (four types of its linearization), Freundlich, Temkin, and Harkins–Jura isotherm models. The fits of the results are estimated according to the Langmuir isotherm, with a maximum adsorption capacity of 17.39 mg/g. The pseudo-second-order model was able to describe kinetic results. The data obtained throughout the study prove that this novel material represents a potential low-cost adsorbent for copper adsorption with improved adsorption capacity and magnetic separation capability compared with raw fly ash.

Biosorption of Cadmium onto Pseudomonas fluorescens: Application of Isotherm and Kinetic Models

2010 ◽  
Vol 171-172 ◽  
pp. 49-52 ◽  
Author(s):  
Chang Li Yu ◽  
Zhi Peng Lu ◽  
Fa Zhi Ge ◽  
Er Li Zhao
Keyword(s):  
Pseudomonas Fluorescens ◽  
Functional Groups ◽  
Metal Ion ◽  
Freundlich Isotherm ◽  
Industrial Effluents ◽  
Rate Equations ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Kinetics Of Adsorption ◽  
Isotherm And Kinetic Models

The present study was undertaken to evaluate the feasibility of Pseudomonas fluorescens biomass for the removal of cadmium ions from aqueous solutions. Batch experiments were performed to study the adsorption of cadmium on pH, Pseudomonas fluorescens biomass adsorbent with respect to initial Cd(II) concentration, contact time and biomass dose. The experimental data were modeled by Langmuir and Freundlich isotherm models. Langmuir model resulted in the best fit of the adsorption data. The maximum adsorption capacity for Cd(II) was 66.25 mg/g (pH 5.0 and 5 g/L biomass dose). Kinetics of adsorption followed second-order rate equations. The FTIR results of Pseudomonas fluorescens biomass showed that biomass has different functional groups and these functional groups are able to react with metal ion in aqueous solution. The results of the present study suggest that Pseudomonas fluorescens biomass can be used beneficially in treating industrial effluents containing heavy metal ions.

scholarly journals Phenol adsorption from wastewater using cashew nut shells as adsorbent

2018 ◽  
Vol 7 (3) ◽  
pp. 966
Author(s):  
Kartik Kulkarni ◽  
Varsha Sudheer ◽  
C R Girish
Keyword(s):  
Agricultural Waste ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Multilayer Adsorption ◽  
Phenol Adsorption ◽  
Cashew Nut ◽  
Experimental Parameters ◽  
Order Kinetic Model

The potential of agricultural waste cashew nut shells as an adsorbent for removing phenol from wastewater is presented in this paper. The adsorbent was treated with 3M sulphuric acid in order to improve the properties. The experimental parameters such as adsorbent dosage, concentration and temperature were optimized with response surface methodology (RSM). The isotherm data were tested with different isotherm models and it obeyed Freundlich Isotherm showing the multilayer adsorption. The kinetic data satisfied pseudo-first order kinetic model. The maximum adsorption capacity was calculated to be 35.08 mg/g proving the capability of cashew nut shells for removing phenol from wastewater.  

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