scholarly journals Study of the adsorption capacity of Fe(II) dissolved in water by using a mineral rich in Manganese Dioxide (MnO2) from Colombia

DYNA ◽  
2016 ◽  
Vol 83 (196) ◽  
pp. 223-228 ◽  
Author(s):  
Jhonnathan Machado-Infante ◽  
Gustavo Ramírez-Caballero ◽  
Martha Juliana Barajas Meneses

<p>In Colombia, a mineral rich in MnO<sub>2</sub> is extracted from the mines of Mallama, Nariño. In this work we studied the adsorption capacity of this mineral for Fe(II) dissolved in aqueous solution of open systems. The characterization was done through ICP-AES, XRF and Raman spectroscopy. The effect of different pretreatments on the mineral with oxidizing agents such as KMnO<sub>4</sub> and NaClO was evaluated. Studies of equilibrium and kinetics of adsorption showed that the mechanism fits well to the Langmuir isotherm and its kinetics to a model of pseudo-second order. At the conditions studied was found that the adsorption capacity for the mineral modified with KMnO<sub>4</sub> and NaOCl were 59.209 and 51.279 mg/g respectively. It is concluded that the mineral is a potential alternative in water treatment.</p>

2017 ◽  
Vol 13 (27) ◽  
pp. 425
Author(s):  
Azeh Yakubu ◽  
Gabriel Ademola Olatunji ◽  
Folahan Amoo Adekola

This investigation was conducted to evaluate the adsorption capacity of nanoparticles of cellulose origin. Nanoparticles were synthesized by acid hydrolysis of microcrystalline cellulose/cellulose acetate using 64% H3PO4 and characterized using FTIR, XRD, TGA-DTGA, BET and SEM analysis. Adsorption kinetics of Pb (II) ions in aqueous solution was investigated and the effect of initial concentration, pH, time, adsorbent dosage and solution temperature. The results showed that adsorption increased with increasing concentration with removal efficiencies of 60% and 92.99% for Azeh2 and Azeh10 respectively for initial lead concentration of 3 mg/g. The effects of contact time showed that adsorption maximum was attained within 24h of contact time. The maximum adsorption capacity and removal efficiency were achieved at pH6. Small dose of adsorbent had better performance. The kinetics of adsorption was best described by the pseudo-second-Order model while the adsorption mechanism was chemisorption and pore diffusion based on intra-particle diffusion model. The isotherm model was Freundlich. Though, all tested isotherm models relatively showed good correlation coefficients ranging from 0.969-1.000. The adsorption process was exothermic for Azeh-TDI, with a negative value of -12.812 X 103 KJ/mol. This indicates that the adsorption process for Pb by Azeh-TDI was spontaneous. Adsorption by Azeh2 was endothermic in nature.


Author(s):  
Qingqing Liu ◽  
Xiaoyan Li

The activated MgO was synthesized by microwave homo-precipitator method and characterized by SEM, EDS and FT-IR methods. It was used to adsorption of U(VI) from aqueous solution with batch system. The paper discussed the effect of pH, temperature, contact time, adsorbent dose and initial U(VI) concentration on the adsorption. The results showed that activated MgO has good adsorption capacity for U(VI), the removal rate and equilibrium adsorption capacity reached 83.5% and 84.04mg·g−1 at pH 5.0, 15mg dose and 313K,respectively. The adsorption kinetics of U(VI) onto activated MgO were better fitted with pseudo-second-order kinetic.The adsorption isotherm data were fitted well to Freundlich isotherm model.The thermodynamic parameters showed that the adsorption process is endothermic and spontaneous.


2010 ◽  
Vol 178 ◽  
pp. 8-16
Author(s):  
Liang Dong Feng ◽  
Bo Qing Chen ◽  
Ying Ying Shi ◽  
Ying Wei Guo ◽  
Jing Huang ◽  
...  

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.


2019 ◽  
Vol 22 (6) ◽  
pp. 310-316 ◽  
Author(s):  
Thamrin Azis ◽  
La Ode Ahmad ◽  
Fajrin E. Rosa ◽  
Laode Abdul Kadir

Heavy metals concentrations exceeding the recommended threshold are hazardous for the environment, so there is a need for handling it safely. The purpose of this research was to determine the adsorption capacity and kinetics of adsorption. This research uses an adsorption method in the process of removing Pb(II) heavy metal ions using persimmon tannin gel. Besides the influence of contact time, pH, and the concentration of Pb(II) metal ions on adsorption, a kinetics study was also carried out. The adsorption rate is obtained through the adsorption rate constant (K) and the reaction order generated from the kinetics model. Based on the results of the research, showed the optimum adsorption process, which is 20 minutes and at a pH of 5. The maximum adsorption capacity of 17.62 mg/g with the value of the standard energy changes of Gibbs adsorption (-ΔG° = -14.274 kJ/moll) indicates that the adsorption takes place through physical interaction. The kinetic adsorption gives the adsorption rates a constant of, k = 0.008231 g/mg.min.


2014 ◽  
Vol 937 ◽  
pp. 9-16
Author(s):  
Xiao Mei Zhang ◽  
Hong Zhan Li ◽  
Man Li Cao ◽  
Chao Yue Chen

A crosslinked β-cyclodextrin (β-CD) polymer (PCD) was synthesized by using maleamic acid as a crosslinked agent, and its adsorption behavior for basic fuchsin in aqueous solution was investigated. The adsorption isotherms could be well fitted by the Langmuir adsorption equation. On the basis of the Langmuir analysis, the maximum adsorption capacities were determined to be 33.56 mg·g-1 at 308K. The kinetics of adsorption followed the pseudo-second-order model.


2021 ◽  
Vol 10 (1) ◽  
pp. 59-66
Author(s):  
Son Le Lam ◽  
Phu Nguyen Vinh ◽  
Hieu Le Trung ◽  
Tan Le Thua ◽  
Nhan Dang Thi Thanh ◽  
...  

Glucomannan/graphene oxide (GM/GO) hydrogel was synthesized by using calcium hydroxide as the crosslinker. The synthesized material was characterized by using IR, XRD, SEM, EDX and RAMAN technology. The composite hydrogel was used for removal of organic dyes from aqueous solution. The results showed that the GM/GO hydrogel had a porous structure and a high adsorption capacity toward methylene blue (MB). The pseudo-second-order kinetic model could fit the rate equation of MB adsorption onto the GM/GO hydrogel. The adsorption of MB onto GM/GO hydrogel was a spontaneous process. In addition, the equilibrium adsorption isotherm data indicated that equilibrium data were fitted to the Langmuir isotherm and the maximum dye adsorption capacity was 198,69 mg.g-1. Moreover, the hydrogel was stable and easily recovered and adsorption capacity was around 97% of the initial saturation adsorption capacity after being used five times.


2020 ◽  
Vol 32 (7) ◽  
pp. 1549-1556
Author(s):  
Abdulaziz Ali Alomari

The aim of this work is to investigate the use of eggshell for adsorption of Cr(VI) from aqueous solution and the effect of thermal treatment as well as coating with Fe2O3 of eggshell on the extraction percent of Cr(VI). The XRD, FTIR and SEM techniques proved that the eggshell mainly composed of calcite rhombohedral structure in addition to a trace of quartz silica residual protein fibers. Heating at 550 ºC does not decompose eggshell but decomposes the residual protein. The effect of pH, weight of eggshell adsorbent, contact time, and initial concentration of Cr(VI) ions on the adsorption of Cr(VI) on eggshell sorbents were determined under static conditions by the batch equilibrium technique. The sorption kinetic as well as mechanistic isotherm parameters of Cr(VI) on the eggshell sorbent, were analyzed. It was concluded that the adsorption of Cr(VI) on eggshell increases as pH increases in the range 3-7, then, with decreases at higher pH. The extraction percent of Cr(VI) increases with an increase in the dosage of eggshell sorbents. The optimum dosage of eggshell adsorbents was found to be 5 g after which the extraction percent of Cr(VI) did not marked increase. The extraction percent of Cr(VI) by eggshell sorbents rapidly increases within 60 min followed by a slower extraction after that when maximum adsorption was reported. The adsorption capacity of Cr(VI) ions is slightly reduced in case of heated eggshell due to the change that occurs in the pore size distribution and structure of eggshell during heating. Hence, the thermal treatment and coating with Fe2O3 do not affect the chemical structure of eggshell sorbents. The adsorption kinetics data were best fitted with the pseudo-second-order equation and the adsorption isotherms were best fitted with the Langmuir isotherm model.


2010 ◽  
Vol 160-162 ◽  
pp. 1804-1809
Author(s):  
Qiang Bi ◽  
Juan Qin Xue ◽  
Ying Juan Guo ◽  
Yu Jie Wang ◽  
Yun Feng Xue

The adsorption of cadmium in simulated wastewater by chitosan was investigated. The influence of temperature, contact time and pH on adsorption efficiency of cadmium was examined. Some related mathematical models were used in the fitting of experimental data. The results showed that at room temperature, the optimum pH of adsorption is between 4 and 7. At lower pH values, a strong competition existed between cadmium ions and protons for sorption sites and the sorption efficiency was decreased. After 60 minutes the adsorption equilibrium can be achieved. Chitosan is very effective at removing cadmium with the maximum adsorption capacity is 112.05mg•g-1. The adsorption kinetic curves agree with the pseudo-second-order adsorption kinetic equations and the adsorption isotherms could be well described by Langmuir isotherm equations.


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