Sorption of Cr(III) ion from aqueous solution by two kinds of modified diatomite

2012 ◽  
Vol 66 (6) ◽  
pp. 1340-1347 ◽  
Author(s):  
Er Li ◽  
Xiangying Zeng
Keyword(s):  
Aqueous Solution ◽  
Manganese Oxide ◽  
Solution Concentration ◽  
Ion Adsorption ◽  
Ion Removal ◽  
Adsorption Capacities ◽  
Synthetic Solution ◽  
And Performance ◽  
Modified Diatomite ◽  
Better Than

Raw diatomite modified by microemulsion (DMM) and manganese oxide (MnD) were used for the removal of Cr(III) ions from aqueous solution. The characteristics and performance of these two types of modified diatomite on Cr(III) ion adsorption were compared. The results indicate that the Cr(III) ion adsorption capacities of diatomite were considerably improved after modifications by manganese oxide (MnO) and microemulsion. The surface area of MnD was increased because of the formation of MnO on the diatomite surface, and that of DMM was promoted owing to the existence of the hydrolyzed aromatic acid. Because of the stronger surface ionized function, the adsorption performance of Cr(III) ions in DMM was better than that in MnD. Within the experimental range of pH (i.e. 2.2–6.3), the Cr(III) ion removal of DMM (35–70%) was higher than that of MnD (33–59%) owing to the different electrostatic forces between the Cr(III) ion and the surface of the modified diatomite. The Cr(III) ion removal in MnD and DMM was improved with the increase of synthetic solution concentration in volumes from 0 to 2,500 mL.

Synthesis of a Fe/Ca-based phosphate material and its application for adsorption of uranium ions from aqueous solution

2021 ◽  
pp. geochem2021-052
Author(s):  
Haiyan Liu ◽  
Weimin Zhang ◽  
Jingyi Mo ◽  
Zhen Wang ◽  
Jiahong Chen ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Sol Gel ◽  
Steel Slag ◽  
Single Layer ◽  
Zero Valent Iron ◽  
Separation Coefficient ◽  
Ion Adsorption ◽  
Ion Removal ◽  
Nano Zero Valent Iron

Uranium (U) ion contamination in aquatic systems has received considerable attention worldwide. In this paper, an adsorption material was synthesized with Fe/Ca-based phosphate (CFB-PM) by a sol-gel method. The effect of pH, reaction time and initial concentration of U ions on its capacity of removing U ions from aqueous solution was investigated by static batch experiments. Comparative studies of U ion removal by CFB-PM with four sorbents, namely: nano zero-valent iron (nZVI), hydroxyapatite (HAP), hydroxyapatite-loaded nano zero-valent iron (HAP@nZVI) and high basicity steel slag loaded hydroxyapatite (HBSS@HAP), were performed. Results showed that U ion adsorption capacity of CFB-PM was better than that of nZVI, HAP, HAP@nZVI and HBSS@HAP. The adsorption capacity showed a decreasing order as: CFB-PM (643.34 mg/g) > HAP (549.86 mg/g) > HBSS@HAP (321.82 mg/g) > HAP@nZVI (153.62 mg/g) > nZVI (102.65 mg/g). SEM-EDS examination suggested that the adsorbed U ions were mainly in the form of spheres, sheets or petals on the surfaces of CFB-PM. XRD detection revealed several U-bearing mineral phases (i.e. Ca(UO2)2(PO4)2·3H2O, HPUO6·4H2O and (UO2)3PO4·4H2O). The U ion adsorption behaviors were further explored by FTIR spectroscopy. The uranium ion adsorption process of CFB-PM could be well described by quasi-second-order adsorption kinetics model and the Langmuir adsorption isotherm model. The separation coefficient (RL) was close to zero, indicating that U ion adsorption was dominated by single-layer chemisorption. The findings reported in this study have implications for applying the synthesized material for remediation of U ion-contaminated groundwater.

Adsorption of Mercury(II) Ion in Aqueous Solution by Using Bentonite-Based Monolith

2021 ◽  
Vol 885 ◽  
pp. 77-84
Author(s):  
Darmadi ◽  
Mahidin ◽  
Siti Syifa Azzahra ◽  
Munadiya Masrura
Keyword(s):  
Aqueous Solution ◽  
Metal Removal ◽  
Batch Reactor ◽  
Heavy Metal Removal ◽  
Solution Concentration ◽  
Environmental Safety ◽  
Adsorption Efficiency ◽  
Ion Removal ◽  
Non Linear ◽  
Langmuir Constants

The removal of mercury from the waterbody remains a severe challenge in ensuring environmental safety due to its highly toxic and non-biodegradable properties. Adsorption is an evidently effective method for heavy metal removal in water. This research aims to study the mercury (II) ion adsorption behavior in aqueous solution onto extruded natural bentonite in monolithic structure, bentonite-based monolith (BBM) adsorbent. BBM was characterized by XRD, BET, and SEM, the results verify BBM could improve adsorption performance assumed on its structure. Adsorption efficiency, isotherm model, and adsorption kinetic were investigated. Experiments were performed in a lab-scale batch reactor with mercury solution concentration varied from 1 to 5 mg/L. The maximum adsorption efficiency discovered to be 63,9%. The experimental data fitted well to Langmuir isotherm (non-linear) and kinetic model pseudo first order (non-linear), revealing the maximum monolayer capacity (Qo) of BBM to be 0,187 mg/g with Langmuir constants KL and aL are 0,215 L/g dan 1,151 L/mg respectively. These value confirms that BBM adsorbent encompasses tremendous potential for mercury (II) ion removal in a solution.

Modification of granular activated carbon using low molecular weight polymer for enhanced removal of Cu2 +  from aqueous solution

2007 ◽  
Vol 56 (9) ◽  
pp. 95-101 ◽  
Author(s):  
C.Y. Yin ◽  
M.K. Aroua ◽  
W.M.A.W. Daud
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Freundlich Isotherm ◽  
Initial Solution ◽  
Batch Adsorption ◽  
Solution Ph ◽  
Molecular Weight Polymer ◽  
Adsorption Capacities ◽  
Surface Impregnation ◽  
Better Than

Palm shell activated carbon was modified via surface impregnation with polyethyleneimine (PEI) to enhance removal of Cu2 +  from aqueous solution in this study. The effect of PEI modification on batch adsorption of Cu2 +  as well as the equilibrium behavior of adsorption of metal ions on activated carbon were investigated. PEI modification clearly increased the Cu2 +  adsorption capacities by 68% and 75.86% for initial solution pH of 3 and 5 respectively. The adsorption data of Cu2 +  on both virgin and PEI-modified AC for both initial solution pH of 3 and 5 fitted the Langmuir and Redlich–Peterson isotherms considerably better than the Freundlich isotherm.

scholarly journals Removal of Cu2+ Ions from Aqueous Solutions by Carbon Nanotubes

2003 ◽  
Vol 21 (5) ◽  
pp. 475-485 ◽  
Author(s):  
Yan-Hui Li ◽  
Zhaokun Luan ◽  
Xu Xiao ◽  
Xiangwen Zhou ◽  
Cailu Xu ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Adsorption Capacity ◽  
Kinetic Curve ◽  
Crystalline Form ◽  
Ion Adsorption ◽  
Ion Concentrations ◽  
Ion Removal ◽  
A Value

Carbon nanotubes (CNTs), a new crystalline form in the carbon family, have been shown to be an effective adsorbent for Cu2+ ion removal from aqueous solution. After oxidation with nitric acid, the adsorption capacity of the oxidized CNTs towards Cu2+ ions at a pH of 5.2 reached 27.6 mg/g, compared to a value of only 14.4 mg/g for the as-grown CNTs under the same circumstances. Increasing the pH to 5.4 led to 95% removal of Cu2+ ions with the oxidized CNTs, whereas with the as-grown CNTs it was necessary to increase the pH to 8.6 to achieve the same extent of removal. The Cu2+ ion adsorption capacity increased with increasing CNT dosage for the different initial Cu2+ ion concentrations. The kinetic curve for adsorption of the Cu2+ ions suggested that not only the outer surfaces but also inner cavities and inter-layers in the structures of the CNTs were responsible for the removal of the ion from aqueous solutions.

scholarly journals Effect of zinc oxid on the bentonite ability for removing Methylene blue from solution

2013 ◽  
Vol 10 (2) ◽  
pp. 442-448
Author(s):  
Baghdad Science Journal
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Zinc Oxide ◽  
Solid Phase ◽  
Langmuir Model ◽  
Batch Adsorption ◽  
Adsorption System ◽  
Freundlich Model ◽  
Adsorption Capacities ◽  
Better Than

A batch adsorption system was applied to study the adsorption of methylene blue from aqueous solution by Iraqi bentonite and treated bentonite with different amount of zinc oxide (ZnO). The adsorption capacities of methylene blue onto bentonite were evaluated. The equilibrium between liquid and solid phase was described by Langmuir model better than the Freundlich model. Langmuir and Freundlich constants have been determined. The separation factor or equilibrium parameter, RL which is used to predict if an adsorption system is favourable or unfavourable was calculated for all cases.

scholarly journals Modeling of Solid-Fluid non-catalytic Processes for Nickel Ion Removal

2020 ◽  
Vol 71 (7) ◽  
pp. 4-15 ◽  
Author(s):  
Gabriela Buema ◽  
Nicoleta Lupu ◽  
Horia Chiriac ◽  
Gabriela Ciobanu ◽  
Olga Kotova ◽  
...  
Keyword(s):  
Basic Structure ◽  
Solution Concentration ◽  
Nickel Ion ◽  
Nickel Ions ◽  
Ion Removal ◽  
Adsorption Capacities ◽  
New Material ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Order Four

The aim of this study is modeling of the process of Ni(II) removal onto new materials synthesized by a facile coprecipitation method. The literature presents different surfactants intercalated on MgAl-LDH with applicability for nickel ions removal, but the researches on the use of this material ��as cast�� as adsorbent for Ni(II) ions are limited, it is reason to develop this study. The morphology, chemical composition, and the basic structure of the new material were analyzed by SEM, EDAX, BET, XRD and FT-IR. The kinetic modeling was performed using the pseudo-first-order, four-type linear pseudo-second-order, and intraparticle diffusion. The experimental data demonstrated that the adsorption process is very fast in the first 20 minutes and reach equilibrium after 50 min. The maximum adsorption capacities of the adsorbent are in the range of 36.5-68.18 mg/g, for the 200-500 mg/L initial solution concentration.

Application Fuzzy Logic System for Accurate Sheet Trim Shower Position

2019 ◽  
Vol 3 (1) ◽  
pp. 186-192
Author(s):  
Yudi Wibawa
Keyword(s):  
Fuzzy Logic ◽  
Fuzzy Logic Controller ◽  
Dc Motor ◽  
Automation System ◽  
Paper Making ◽  
System A ◽  
Accurate Position ◽  
And Performance ◽  
Better Than ◽  
Logic System

This paper aims to study for accurate sheet trim shower position for paper making process. An accurate position is required in an automation system. A mathematical model of DC motor is used to obtain a transfer function between shaft position and applied voltage. PID controller with Ziegler-Nichols and Hang-tuning rule and Fuzzy logic controller for controlling position accuracy are required. The result reference explains it that the FLC is better than other methods and performance characteristics also improve the control of DC motor.

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