Application of fly ash-based geopolymer for removal of cesium, strontium and arsenate from aqueous solutions: kinetic, equilibrium and mechanism analysis

Abstract Geopolymerization is a developing reaction process for the utilization of solid wastes. In the present study, fly ash-based geopolymer and its derivative (Fe(II)-modified geopolymer) were synthesized and characterized using XRD, SEM, FTIR, BET, UV-Vis DRS as well as TG-DTA, and adopted as adsorbents for removal of Cs+ and Sr2+, and from solutions. Each sorption kinetic was well fitted to the pseudo-second-order model. The sorption of Cs+ and Sr2+ onto original geopolymer were better fitted to the Langmuir model. However, the Freundlich model is more befitting for sorption of onto Fe(II)-modified geopolymer. The free energies calculated from the D-R isotherm indicated that the sorption for Cs+ and Sr2+ were dominantly ion exchanges. Ring size plays a decisive role in ion exchanges for both Cs+ and Sr2+. Furthermore, the arrangement of SiO4 and AlO4 tetrahedrons has significant impacts on the ion exchange of Sr2+. XPS results indicated that a part of Fe2+ in Fe (II)-modified geopolymer had been oxidized to Fe3+ after sorption. Precipitation of FeAsO4 could partially contribute to the arsenate removal from solution. sorption has also occurred through the formation of inner-sphere complexes via ion exchange reaction, which could be predominantly attached by bidentate linkages.

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ELUTION BEHAVIOR OF PHOSPHATE CONTAINED IN Mg/Fe AND Zn/Fe LAYERED DOUBLE HYDROXIDES

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512003108 ◽

2012 ◽

Vol 06 ◽

pp. 156-161 ◽

Cited By ~ 1

Author(s):

Masashi Kurashina ◽

Tomohiro Amatsu ◽

Takaaki Ochi ◽

Nozomi Ohigashi ◽

Eiji Kanezaki

Keyword(s):

Ion Exchange ◽

Concentrate Solution ◽

Sulfate Solution ◽

Carbonate Solution ◽

Solution Ph ◽

Ion Exchange Reaction ◽

Pseudo Second Order ◽

Elution Behavior ◽

Double Hydroxide ◽

Double Hydroxides

Layered double hydroxide (LDH) is a layered hydroxide and exchangeable anion is intercalated in its interlayer. Application of the LDH as a controlled-release material of interlayer anions has become of interest, thus it is important to clarify the elution behavior of interlayer anions. We synthesized hydrogenphosphate-intercalated Mg / Fe and Zn / Fe LDH and elution of phosphate from these LDH were tested in deionized water, sodium chloride solution, sodium sulfate solution, and sodium carbonate solution. For Mg / Fe LDH, the amount of eluted phosphate increased with time and reached to maximum that increased as higher concentrate solution was used. The elution of phosphate from Mg / Fe LDH could be described by the pseudo second-order equation. This elution behavior was explained as ion-exchange reaction of phosphate with sulfate or carbonate in tested solution by means of kinetic simulation using Runge-Kutta method. In the eluted solution, metal ions contained in the LDH were detected and its amount depended on pH of the tested solution, that is, amounts of eluted Mg and Zn ions were small at higher pH (ca. 10) for Mg / Fe and Zn / Fe LDH respectively, but large amount of Zn ion was detected when 2.03 mol·l-1 carbonate solution (pH = 13) was used. Thus elution of phosphate was caused by two main reactions: ion exchange and decomposition of the LDH.

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Preparation of Alginate Polymer Gel Pellets and its Adsorption on Acid Dyes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.993.1426 ◽

2020 ◽

Vol 993 ◽

pp. 1426-1431

Author(s):

Bei Gang Li ◽

Hai Yang Yin

Keyword(s):

Ion Exchange ◽

Adsorption Kinetics ◽

Polymer Gel ◽

Acid Dyes ◽

Environmental Friendliness ◽

Adsorption Effect ◽

Ion Exchange Reaction ◽

Pseudo Second Order ◽

Acid Orange Ii ◽

Stable Network

A novel calcium alginate (SA/Ca) gel pellet adsorbent was prepared by ion exchange reaction and polymerization between sodium alginate (SA) and Ca2+ in the solution, and characterized by SEM, EDS, FTIR and XRD. Taking acid orange II ( AO II) dye as the adsorption object, the influence of some important conditions about preparation and adsorption on SA/Ca properties was discussed in detail. The adsorption kinetics were studied. The results show that SA/Ca adsorbent has good adsorption effect on AO II dye under the conditions of the mass concentration ratio 2 : 5 of SA and CaCl2 solutions and reaction time of 2h at 25°C. When the adsorbent dosage is 4g/L and initial dye concentration of natural pH is 1000 mg/L, the adsorption equilibrium can basically reach in 180 min at 25°C with the adsorption capacity of 225mg/g and more than 90% of removal efficiency. The adsorption kinetics fully fit pseudo-second order model. The characterization results indicate that the SA powder is composed of various irregular particles, while dry SA/Ca solid are all pellets with diameter of about 1mm. The surface of inhomogeneous spheres is stacked with obstacles, and folds and ravines coexist. Ca2+ and most Na+ in SA molecule carried out ion exchange and formed a stable network-structure polymer SA/Ca gel pellets, which can effectively remove acid dyes from wastewater, and are easy to be separated after adsorption. As a biopolymer adsorbent with simple preparation method, environmental friendliness and non-toxic side effects, SA/Ca has good development potential and application prospects.

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Application of Alginate Extraction Residue for Al(Iii) Ions Biosorption: A Complete Batch System Evaluation

10.21203/rs.3.rs-290880/v1 ◽

2021 ◽

Author(s):

Heloisa Pereira de Sá Costa ◽

Meuris Gurgel Carlos da Silva ◽

Melissa Gurgel Adeodato Vieira

Keyword(s):

Adsorption Mechanism ◽

Adsorptive Capacity ◽

Maximum Adsorption Capacity ◽

Batch Mode ◽

Freundlich Model ◽

Pseudo Second Order ◽

Physical Interactions ◽

Biomass Dosage ◽

Alginate Extraction ◽

Kinetic Equilibrium

Abstract The residue derived from the alginate extraction from S. filipendula was applied for the biosorption of aluminum from aqueous medium. The adsorptive capacity of the residue (RES) was completely evaluated in batch mode. The effect of pH, contact time, initial concentration and temperature was assessed through kinetic, equilibrium and thermodynamic studies. The biosorbent was characterized prior and post-Al biosorption by N2 physisorption, Hg porosimetry, He picnometry and thermogravimetry analyses. Equilibrium was achieved in 60 minutes. Kinetics obeys pseudo-second order model at aluminum higher concentrations. Isotherms followed Freundlich model at low temperature (293.15 K) and D-R or Langmuir model at higher temperatures (303 and 313 K). Data modeling indicated the occurrence of both chemical and physical interactions in the aluminum adsorption mechanism using RES. The maximum adsorption capacity obtained was of 1.431 mmol/g at 293 K. The biosorption showed a spontaneous, favorable and exotherm character. A simplified batch design was performed, indicating that the residue is a viable biosorbent, achieving high percentages of removal using low biomass dosage.

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Comparative studies on the adsorption of Pb(II) ions by fly ash and slag obtained from CFBC technology

Polish Journal of Chemical Technology ◽

10.2478/pjct-2019-0042 ◽

2019 ◽

Vol 21 (4) ◽

pp. 72-81 ◽

Cited By ~ 1

Author(s):

Tomasz Kalak ◽

Ryszard Cierpiszewski

Keyword(s):

Fly Ash ◽

Circulating Fluidized Bed ◽

Chemical Properties ◽

Temperature Treatment ◽

High Temperature Treatment ◽

Maximum Adsorption Capacity ◽

Fluidized Bed Combustion ◽

Freundlich Model ◽

Pseudo Second Order ◽

Physical And Chemical

Abstract Fly ash and slag were examined for the removal processes of Pb(II) ions from water in batch experiments under different conditions of adsorbent dosage, initial concentration, pH and contact time. The materials are industrial waste generated from the high temperature treatment of sewage sludge by the circulating fluidized bed combustion (CFBC) technology. Physical and chemical properties, as well as adsorption efficiency and calculated maximum adsorption capacity of Pb(II) ions were determined using a variety of methods. The kinetic analysis revealed that the adsorption process is better described by the pseudo-second order equation and it is well fitted to the Freundlich model.

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Removal of phosphate from coating wastewater using magnetic Fe-Cu bimetal oxide modified fly ash

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2015.105 ◽

2015 ◽

Vol 6 (3) ◽

pp. 430-436 ◽

Cited By ~ 7

Author(s):

Ke Xu ◽

He Tao ◽

Tong Deng

Keyword(s):

Fly Ash ◽

Langmuir Model ◽

Experimental Results ◽

Phosphate Adsorption ◽

Order Model ◽

Freundlich Model ◽

Maximum Capacity ◽

Adsorption Time ◽

Pseudo Second Order ◽

Modified Fly Ash

In this work, magnetic Fe-Cu bimetal oxide modified fly ash was used to remove phosphate from coating wastewater. The influences of pH, dosage amount and adsorption time on the removal of phosphate were investigated. The experimental results showed that pH had a significant effect on the adsorption of phosphate. The removal percentage of phosphate reached a maximum at pH 10. The removal efficiency of phosphate increased with the increase in adsorbent dosage. A kinetic study showed that the phosphate adsorption was well described by a pseudo second order model. The adsorption isotherm of phosphate could be described by the Langmuir model and Freundlich model. The Langmuir maximum capacity Q0 was 12.69 mg/g and the value of n of the Freundlich model was 3.82. The experimental results indicated that magnetic Fe-Cu bimetal oxide modified fly ash was a potential adsorbent for the removal of phosphate from the wastewater.

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Photoassisted Production of O2-• and H2 in Aqueous Medium Stimulated by Polythiophene in ZSM-5 Zeolite Channels

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19990149 ◽

1999 ◽

Vol 64 (1) ◽

pp. 149-156 ◽

Cited By ~ 7

Author(s):

Gabriel Čík ◽

František Šeršeň ◽

Alena Bumbálová

Keyword(s):

Reactive Oxygen Species ◽

Ion Exchange ◽

Visible Light ◽

Aqueous Medium ◽

Exchange Reaction ◽

Epr Spectroscopy ◽

Reactive Oxygen ◽

Oxygen Species ◽

Water Reduction ◽

Ion Exchange Reaction

The formation of reactive oxygen species due to irradiation by a visible light of the polythiophene deposited in ZSM-5 zeolite channels in aqueous medium has been studied. Polymerization of thiophene was carried out in zeolite channels after the ion-exchange reaction of Na+ for Fe3+. By means of EPR spectroscopy, the temporarily generated 1O2 in irradiated aqueous medium was proved. The formation of O2-• was confirmed by the reduction of Fe3+-cytochrome c. Irradiation led to the water reduction to hydrogen.

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Insight into the enhanced photocatalytic properties of AgBr/Ag4P2O7 composites synthesized via in situ ion exchange reaction

Journal of Environmental Chemical Engineering ◽

10.1016/j.jece.2020.104889 ◽

2021 ◽

Vol 9 (1) ◽

pp. 104889

Author(s):

Wyllamanney da S. Pereira ◽

Fabrício B. Destro ◽

Cipriano B. Gozzo ◽

Edson R. Leite ◽

Júlio C. Sczancoski

Keyword(s):

Ion Exchange ◽

Exchange Reaction ◽

Photocatalytic Properties ◽

Ion Exchange Reaction ◽

Insight Into

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Removal of Mg from spring water using natural clinoptilolite

Clay Minerals ◽

10.1180/claymin.2012.047.1.81 ◽

2012 ◽

Vol 47 (1) ◽

pp. 81-92 ◽

Cited By ~ 1

Author(s):

S. Tomić ◽

N. Rajić ◽

J. Hrenović ◽

D. Povrenović

Keyword(s):

Ion Exchange ◽

Kinetic Studies ◽

Spring Water ◽

Zeolite A ◽

Zeolitic Tuff ◽

Rate Limiting Step ◽

Intra Particle Diffusion ◽

Pseudo Second Order ◽

Natural Clinoptilolite ◽

Rate Limiting

AbstractNatural zeolitic tuff from Brus (Serbia) consisting mostly of clinoptilolite (about 90%) has been investigated for the reduction of the Mg concentration in spring water. The sorption capacity of the zeolite is relatively low (about 2.5 mg Mg g-1for the initial concentration of 100 mg Mg dm-3). The zeolitic tuff removes Mg from water solutions by ion exchange, which has been demonstrated by energy dispersive X-ray analysis (EDS). The extent of ion exchange was influenced by the pH and the initial Mg concentration. Kinetic studies revealed that Lagergen's pseudo-second order model was followed. Intra-particle diffusion of Mg2+influenced the ion exchange, but it is not the rate-limiting step. Rather than having to dispose of the Mg-loaded (waste) zeolite, a possible application was tested. Addition to a wastewater with a low concentration of Mg showed that it could successfully make up for the lack of Mg micronutrient and, accordingly, enabled the growth of phosphate-accumulating bacteriaA. Junii, increasing the amount of phosphate removed from the wastewater.

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