Characterization and adsorption performance of chitosan/diatomite membranes for Orange G removal

e-Polymers ◽  
2016 ◽  
Vol 16 (2) ◽  
pp. 99-109 ◽  
Author(s):  
Xiu-Juan Wu ◽  
Ji-De Wang ◽  
Li-Qin Cao
Keyword(s):  
Adsorption Capacity ◽  
Contact Time ◽  
Ph Value ◽  
Removal Rate ◽  
Composite Membranes ◽  
Second Order ◽  
Inorganic Substances ◽  
Phase Inversion Technique ◽  
Orange G ◽  
Pseudo Second Order

AbstractNovel chitosan/diatomite (CS/DM) membranes were prepared by phase inversion technique to remove anionic azo dyes from wastewater. The fabricated composite membranes exhibited the combined advantages of inorganic substances, diatomites, and polysaccharides. These composite membranes were characterized through Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction analysis. The mechanical properties of the membranes were also evaluated. Adsorption experiments were conducted under varied initial dye concentration, solution pH values, contact time, and adsorbent dosage. The results indicate that pH 3 is the optimal pH value for Orange G adsorption. The CS/DM membranes exhibit the highest adsorption capacity of 588 mg g-1 and removal rate of 94% under an initial dye concentration of 200 mg l-1, contact time of 6 h, and membrane dosage of 8 mg. Langmuir, Freundlich and Redlich-Peterson adsorption models were applied to describe the equilibrium isotherms at different dye concentrations. The equilibrium data was found to be fitted well to the Redlich-Peterson isotherm. Pseudo-first-order and pseudo-second-order kinetics models were used to describe the adsorption of membranes. The adsorption data were well explained by pseudo-second-order models, and also followed by the Elovich model. In addition, these membranes display high adsorption capacity and mechanical performance even after reused for seven times.

Pseudo-Second-Order Kinetics for the Adsorption of Uranyl Ion onto Peat at Different pH Value

2010 ◽  
Vol 113-116 ◽  
pp. 33-36
Author(s):  
Zhi Rong Liu ◽  
Qin Qin Tao ◽  
Chuan Xi Wen
Keyword(s):  
Contact Time ◽  
Adsorption Process ◽  
Adsorption Equilibrium ◽  
Ph Value ◽  
Second Order ◽  
Uranyl Ions ◽  
Batch Tests ◽  
Effects Of Ph ◽  
Pseudo Second Order

Batch tests were used to investigate the effects of pH and contact time on the adsorption capability of peat. The results indicate that adsorption of uranyl ions on peat increase with increasing pH from 1 to 5. However it takes longer contact time to reach the adsorption equilibrium with increase of pH from 1 to 5. The adsorption process can be described by type 1 of the pseudo-second-order kinetics excellently.

scholarly journals Removal of Direct Yellow 50 From Aqueous Solutions Using Chitosan-ISO-Vanillin Derivatives Chelating Polymers

2020 ◽  
Author(s):  
Eman Alabbad
Keyword(s):  
Contact Time ◽  
Removal Rate ◽  
Second Order ◽  
Rate Equations ◽  
Order Kinetic ◽  
Solution Ph ◽  
Modified Chitosan ◽  
Intra Particle Diffusion ◽  
Pseudo Second Order ◽  
Living Organisms

Abstract Background Water contamination has increasingly become a significant problem affecting the welfare of living organisms perceived to be aquatic beneficiaries. The nature and origin of the contaminant always determines the purification techniques. The most common contaminants in wastewater include organic compounds such as dyes that must be eliminated to enhance water purity and safety.Result The results indicate that the removal of DY50 by the modified chitosan was affected by the solution pH, sorbent dosage, initial DY50 concentration, contact time, and temperature. The experimental data were fitted to the Langmuir, Freundlich, and Temkin isotherms, and Langmuir isotherm showed the best fit. The kinetic data were fitted to the pseudo-first-order and pseudo-second-order rate equations. The removal rate was 97.9% by chemisorption components after the three hours at about 0.05 g of sorbent dose and 100 ppm of the Direct Yellow 50 dye initial concentration. The adsorption behavior of the modified chitosan for the removal of DY50 was well-described using the pseudo-second-order kinetic model, Intraparticle diffusion analysis was also conducted. The thermodynamic properties such as free energy (∆G), enthalpy (∆H), and entropy (∆S), in addition to the intra-particle diffusion rate were similarly defined.Conclusion The pH, initial DY50 concentration, sorbent dosage, adsorption temperature, and contact time had a significant effect on the adsorption of DY50 by chitosan-iso-vanillin.

scholarly journals Removal of triphenylmethane dye from aqueous solutions through an adsorption process over waste materials

2020 ◽  
Vol 10 (4) ◽  
pp. 5772-5779
Keyword(s):  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Dye Removal ◽  
Functional Group ◽  
Adsorption Process ◽  
Removal Rate ◽  
Freundlich Isotherm ◽  
Second Order ◽  
Pseudo Second Order ◽  
Best Fit

Water pollution is the most significant issue due to rapid growing industrial development especially textile dye industry. Therefore, the adsorption process experiment was conducted to determine the removal ability of the adsorbent chosen. The removal rate and adsorption capacity of Phenol red and Cresol were analyzed by using eggshell adsorbent in the adsorption process. The experiment was conducted with parameters of initial concentration, dosage, pH and contact time. Results indicated that the removal rate achieved more than 90% and the adsorption capacity exceeded more than 5 mg/g. The functional group before adsorption process eggshell adsorbent and after adsorption process eggshell adsorbent was analyzed by using FTIR (Fourier Transform Infrared Spectroscopy). The study of adsorption isotherm and kinetics model was carried out to identify the efficiency of the eggshell adsorbent reacting with the dye solution. The adsorption isotherm that applied in this research was Langmuir isotherm, Jovanovic isotherm and Freundlich isotherm. Moreover, Pseudo-first-order and Pseudo-second-order chosen were conducted to determine the kinetic studies. In short, eggshell adsorbent is highly effective on dye removal through adsorption capacity. The functional group of the eggshell adsorbent was found such as alcohols, phenol, alkanes, carbonyls, ester, saturated aliphatic, aldehydes, aromatics, 2°amines and phosphorus. For kinetics study, Freundlich isotherm was analyzed as the best fit isotherm model as it achieved the highest R2 value which is closed to 1 and Pseudo-second-order was analyzed as the best fit kinetic model in this experiment. Therefore, eggshell adsorbent is highly effective in dye removal.

scholarly journals Study of the Digestate as an Innovative and Low-Cost Adsorbent for the Removal of Dyes in Wastewater

Processes ◽  
2020 ◽  
Vol 8 (7) ◽  
pp. 852
Author(s):  
Sicong Yao ◽  
Massimiliano Fabbricino ◽  
Marco Race ◽  
Alberto Ferraro ◽  
Ludovico Pontoni ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Contact Time ◽  
Removal Rate ◽  
Low Cost ◽  
Second Order ◽  
Isotherm Models ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Diffusion Kinetic ◽  
Pseudo Second Order

Digestate, as an urban solid waste, was considered as an innovative adsorbent for colorant polluted wastewater. Batch adsorption experiments were carried out using digestate as an adsorbent material to remove various dyes belonging to different categories. The removal rate and adsorption capacity of dyes were evaluated and the dose of digestate, contact time, and initial dye concentration were studied. The maximum removal rate was approximately 96% for Methylene Blue. The equilibrium time for the Methylene Blue was 4 h, while for other dyes, a longer contact time was required to reach the equilibrium. The suspicion of colloidal matter release into the solution from solid fraction of the digestate led to the investigation of the consequence of a washing step of the digestate adsorbent upstream the adsorption experiment. Washed and not washed adsorbents were tested and the differences between them in terms of dye removal were compared. Moreover, experimental data were fitted by pseudo-first order, pseudo-second order, and intra-partial diffusion kinetic models as well as Langmuir, Freundlich, and Sips isotherm models. The results from fitted models showed that the adsorption of various dyes onto the digestate was mostly well fitted by the Langmuir isotherm and pseudo-second-order kinetic model.

Chromium (VI) adsorption onto activated sulfate lignin

2009 ◽  
Vol 4 (2) ◽  
Author(s):  
Nassima Tazrouti ◽  
Moussa Amrani
Keyword(s):  
Adsorption Capacity ◽  
Contact Time ◽  
Analytical Data ◽  
Order Equation ◽  
Second Order ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Adsorption Model ◽  
Chromium Vi ◽  
Pseudo Second Order

Activated lignin having surface area of 1023 m2.g-1 has been prepared from sulfate lignin that was treated by 30 % H2O2 and carbonized at 300 °C in order to test the chromium (VI) adsorption from aqueous solution. The influence of contact time, pH, initial concentration of adsorbent and adsorbate and temperature on the adsorption capacity were investigated. The maximum removal of Cr(VI) was found to be 92,36 % at pH=2 and contact time of 80 min. Optimal concentration of lignin and Cr(VI) were found to be 3.8 g.l-1 and 180 mg.l-1, respectively. The adsorption kinetics was tested pseudo-first-order and pseudo-second-order equation. The analytical data were fitted well in a pseudo-second-order equation and the rate of removal of chromium was found to speed up with increasing temperature. Activation energy for the adsorption process was found to be 18.19 Kj.mol-1. The Langmuir and Freundlich adsorption isotherm models were applied to describe the isotherm and isotherm constants for the adsorption of Cr (VI) on lignin. These constants and correlation coefficients of the isotherm models were calculated and compared. Results indicated that Cr (VI) uptake could be described by the Langmuir adsorption model. The maximum adsorption capacity (qm) of Cr (VI) on lignin was 75.75 mg.g-1 at temperature of 40°C. The dimensionless equilibrium parameter (RL) signified a favorable adsorption of Cr (VI) on lignin and was found between 0.0601 and 0.818 (0<RL<1). The thermodynamic parameters like ΔG°, ΔS° and ΔH° were calculated and it has been found that the reaction was spontaneous and endothermic in nature. This study indicates that lignin has the potential to become an effective and economical adsorbent for removal Cr (VI) from the waste water.

Adsorption Characters of Mn2+ onto Palygorskites Modified by 1, 10-Phenanthroline and Triethylamine

2010 ◽  
Vol 178 ◽  
pp. 8-16
Author(s):  
Liang Dong Feng ◽  
Bo Qing Chen ◽  
Ying Ying Shi ◽  
Ying Wei Guo ◽  
Jing Huang ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Contact Time ◽  
Ph Value ◽  
Order Model ◽  
Kinetics Of Adsorption ◽  
Initial Concentration ◽  
Adsorption Capacities ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Kinetics Of

1, 10-phenanthroline and triethylamine modified palygorskites were prepared by microwave irradiation, and characterized with FT-IR technique. The effects of contact time, adsorbent dosage, and pH value of the initial solution on the adsorption characters of Mn2+ were investigated. The adsorption of Mn2+ from aqueous solutions using 1, 10-phenanthroline or triethylamine modified palygorskites were investigated. Experiment results indicated that 1,10-phenanthroline and triethylamine molecules have been successfully grafted to palygorskite. The adsorption was rapid during the first 5 minuts and equilibrium were attained within 60 minutes in the initial concentration of Mn2+ of 50 and 100 mg•L-1, and fast adsorption in the first 10 minutes and slowly increased with the contact time due to the adsorption of palygorskite. The 1, 10-phenanthroline modified palygorskites had higher adsorption capacity than triethylamine modified palygorskites. Compared with natural palggorskites, the Mn2+ ions adsorption capacities of palggorskite modified by 1, 10-phenanthroline or triethylamine were significantly improved. There were less difference in the adsorption capacity between different dasages of 1, 10-phenanthroline modified palygorskites, but the adsorption capacity of Mn2+ adsorbed onto triethylamine modified palygorskites decreased with increasing the dosages. A Lagergren pseudo-second order model best described the kinetics of adsorption of Mn2+ onto the modified palygorskites.

scholarly journals Efficient Removal of Methyl Orange from Wastewater by Polymeric Chitosan-iso-vanillin

2020 ◽  
Vol 7 (1) ◽  
pp. 16-25
Author(s):  
Eman A. Alabbad
Keyword(s):  
Water Pollution ◽  
Methyl Orange ◽  
Contact Time ◽  
Removal Rate ◽  
Second Order ◽  
Rate Equations ◽  
Order Kinetic ◽  
Solution Ph ◽  
Modified Chitosan ◽  
Pseudo Second Order

Introduction: Water pollution is a serious issue in several countries. In addition, because of limited water resources, the recycling of wastewater is crucial. Consequently, new and effective sorbents are required to reduce the cost of wastewater treatment as well as to mitigate the health problems caused by water pollution. Methods: In this study, the removal of Methyl Orange (MO) dye from wastewater using a chitosan-iso-vanillin polymer was evaluated. The removal of MO from an aqueous solution was studied in a batch system, using the modified chitosan polymer. Results: The results indicate that the removal of MO by the modified chitosan was affected by the solution pH, sorbent dosage, initial MO concentration, contact time, and temperature. The experimental data were fitted to the Langmuir, Freundlich, and Temkin isotherms, and Freundlich isotherm showed the best fit. The kinetic data were fitted to the pseudo-first-order and pseudo-second-order rate equations. Thus, the removal of MO was controlled via chemisorption, and the removal rate was 97.9% after 3 h at an initial MO concentration of 100 ppm and a sorbent dose of 0.05 g. The adsorption behavior of the modified chitosan for the removal of MO was well-described using the pseudo-second-order kinetic model. Intraparticle diffusion analysis was also conducted, and the thermodynamic properties, including entropy (∆S), enthalpy (∆H), and free energy (∆G), were determined. Conclusion: The pH, initial MO concentration, sorbent dosage, adsorption temperature, and contact time had a significant effect on the adsorption of MO by chitosan-iso-vanillin.

scholarly journals Adsorption of Methylene Blue from Aqueous Solution by Pumpkin-Seed Residue

2020 ◽  
Vol 42 (1) ◽  
pp. 10-18
Author(s):  
Tae Hyun Gil ◽  
Wang Heon Lee ◽  
Johng-Hwa Ahn
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Adsorption Capacity ◽  
Contact Time ◽  
Sorption Process ◽  
Second Order ◽  
High Concentration ◽  
Pumpkin Seed ◽  
Freundlich Adsorption Isotherm ◽  
Pseudo Second Order

Objective : Present research discussed the utilization of pumpkin-seed residue (PSR) after oil extraction with methanol as an adsorbent for methylene blue (MB) removal from aqueous solution.Method : The experiment was carried out to evaluate the influence of PSR adsorbent dose (7.5-25 g/L), initial MB concentration (25-200 mg/L), contact time (30-120 min), pH (3-11), and temperature (293-333 K). Adsorption isotherms were modeled with the Langmuir, Freundlich, and Temkin isotherms. The kinetic data were analyzed using pseudo-first-order and pseudo-second-order models.Results and Discussion : A pseudo-equilibrium state was reached within 30 min of contact time at low initial MB concentration (25-50 mg/L) and 90 min at high concentration (100-200 mg/L). Increasing pH and temperature caused an increase in adsorption capacity. Thermodynamic studies demonstrated that the adsorption process was spontaneous with Gibb’s free-energy values ranging between -15.78 to -13.87 kJ/mol and endothermic with an enthalpy value of 0.011 kJ/mol. The adsorption equilibrium data fitted well with the Freundlich adsorption isotherm. The maximum monolayer adsorption capacity was 20.33 mg/g. Tempkin isotherm model clarified that the heat of sorption process was 6.28 J/mol. The adsorption kinetics was found to follow the pseudo-second order kinetics model and its rate constant was 0.002-0.278 g/mg･min.Conclusions : Findings of the present study indicated that the PSR can be successfully used for removal of MB from aqueous solution. Therefore, the PSR was shown to have good potential as a biosorbent for MB removal.

Adsorption of 2,4-Dichlorophenol on Meta-Aramid/Poly (acylic Acid) Composite Nanofibrous Membranes

2012 ◽  
Vol 610-613 ◽  
pp. 551-555 ◽  
Author(s):  
Qi Jun Zhou ◽  
Ran Xu
Keyword(s):  
Adsorption Capacity ◽  
Contact Time ◽  
Removal Rate ◽  
Freundlich Isotherm ◽  
Acidic Ph ◽  
Order Model ◽  
Electrospinning Method ◽  
Pseudo Second Order ◽  
Equilibrium Adsorption Capacity ◽  
Nanofibrous Membranes

Meta-aramid/poly (acylic acid) (PMIA/PAA) composite nanofibrous membranes with diameter between 50-100 nm have been fabricated by electrospinning method. The effect of contact time, temperature, pH and concentration of 2,4-dichlorophenol on the adsorption capacity of the membranes were investigated. The equilibrium adsorption capacity of 2,4-dichlorophenol on PMIA/PAA nanofibrous membranes is 251.61 mg/g. Acidic pH was favorable for the 2,4-dichlorophenol adsorption. Its desorption rate reached 74% in 45 min. After five regeneration cycles, the removal rate of 2,4-dichlorophenol still maintained above 65%. The adsorption of 2,4-dichlorophenol on the membranes fit the Freundlich isotherm model best. Its adsorption kinetics followed a pseudo-second-order model.

Fabrication of a novel graphene oxide/β-FeOOH composite and its adsorption behavior for copper ions from aqueous solution

2015 ◽  
Vol 44 (22) ◽  
pp. 10448-10456 ◽  
Author(s):  
Tingshun Jiang ◽  
Lu Yan ◽  
Lei Zhang ◽  
Yingying Li ◽  
Qian Zhao ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Graphene Oxide ◽  
Adsorption Capacity ◽  
Adsorption Process ◽  
Copper Ions ◽  
Removal Rate ◽  
Second Order ◽  
Adsorption Behavior ◽  
Kinetics Model ◽  
Pseudo Second Order

A graphene oxide/β-FeOOH composite was prepared and its adsorption capacity was evaluated by Cu2+removal. The adsorption process was well fitted with the pseudo-second-order kinetics model. The removal rate of Cu2+reached 93.8%.

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