Titanium Pyrophosphate for Removal of Trivalent Heavy Metals and Actinides Simulated by Retention of Europium

This work addresses the synthesis of titanium pyrophosphate, as well as the characterization and evaluation of the sorption process of europium, for removal of trivalent heavy metals and actinides simulate. The evaluation of the surface properties of titanium pyrophosphate was carried out determining the surface roughness and surface acidity constants. The values obtained from the determination of the surface roughness of the synthesized solid indicate that the surface of the material presents itself as slightly smooth. The FITEQL program was used to fit the experimental titration curves to obtain the surface acidity constants: log⁡K+=3.59±0.06 and log⁡K-=-3.90±0.05. The results of sorption kinetics evidenced that the pseudo-order model explains the retention process of europium, in which the initial sorption velocity was 8.3 × 10−4 mg g−1 min−1 and kinetic constant was 1.8 × 10−3 g mg min−1. The maximum sorption capacity was 0.6 mg g−1. The results obtained from sorption edge showed the existence of two bidentate complexes on the surface.

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Kinetics and adsorption equilibrium of some radionuclides on polyaniline/SiO2 composite

Radiochimica Acta ◽

10.1515/ract-2020-0014 ◽

2021 ◽

Vol 109 (2) ◽

pp. 85-97

Author(s):

Abeer E. Kasem ◽

Ezzat A. Abdel-Galil ◽

Nabil Belacy ◽

Nagwa A. Badawy

Keyword(s):

Adsorption Equilibrium ◽

Sorption Process ◽

Sorption Kinetics ◽

Sorption Behavior ◽

Order Kinetic ◽

Maximum Sorption Capacity ◽

Maximum Sorption ◽

Order Kinetic Model ◽

Langmuir Isotherm Model ◽

Pseudo Second Order

Abstract The sorption kinetics and equilibrium isotherms of zirconium, uranium, and molybdenum ions onto synthetic polyaniline/SiO2 composite (PAn/SiO2) have been studied using batch-sorption techniques. This study was carried out to examine the sorption behavior of the PAn/SiO2 for the removal of Zr(IV), U(VI), and Mo(VI) ions from an aqueous solution. The influence of some parameters on the sorption process was also studied. The maximum sorption for Zr(IV), U(VI), and Mo(VI) ions was achieved at 60 min shaking time. Langmuir isotherm model is the most representative for discussing the sorption process with a maximum sorption capacity of 24.26, 21.82, and 13.01 mg/g for Zr(IV), U(VI), and Mo(VI) ions, respectively. Kinetic modeling revealed that the sorption of all ions follows the pseudo-second-order kinetic model. The results demonstrated that both the external and intra-particular diffusion are taken into account in determining the sorption rate. Thermodynamic parameters like ΔG°, ΔH°, and ΔS° for the sorption process were evaluated. The synthetic composite has been successfully applied for the removal and recovery of U(VI) ions from real solution (monazite leachate) using a chromatographic column packed with PAn/SiO2 composite with a breakthrough capacity equal to 239.70 mg/g.

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Removal of the herbicide 2,4-dichlorophenoxyacetic acid from water by using an ultrahighly efficient thermochemically activated carbon

Hemijska industrija ◽

10.2298/hemind190411019b ◽

2019 ◽

Vol 73 (4) ◽

pp. 223-237

Author(s):

Danijela Bojic ◽

Milos Kostic ◽

Miljana Radovic-Vucic ◽

Nena Velinov ◽

Slobodan Najdanovic ◽

...

Keyword(s):

Activated Carbon ◽

Sorption Capacity ◽

Sorption Process ◽

Sorption Kinetics ◽

Activation Process ◽

Maximum Sorption Capacity ◽

Maximum Sorption ◽

High Sorption ◽

2,4 Dichlorophenoxyacetic Acid ◽

Lagenaria Vulgaris

Lagenaria vulgaris activated carbon (LVAC) was synthesized from Lagenaria vulgaris biomass by treatment with diluted H2SO4 followed by thermo-chemical carbonization and overheated steam activation process and used for removal of the herbicide 2,4-dichlo-rophenoxyacetic acid (2,4-D). Fourier transform infrared spectroscopy (FTIR) indicated that 2,4-D is adsorbed in micropores of the very porous LVAC (665 m2 g-1). LVAC showed high sorption capacity as compared to many previously used sorbents at optimal conditions: the stirring rate of 300 rpm, the sorbent dose of 1.0 g dm-3 and pH from 2 to 7. The experimental maximum sorption capacity of LVAC was 333.3 mg g-1. The pseudo-second-order model and Chrastil model described the 2,4-D sorption kinetics by LVAC. Thermodynamic studies have indicated that the sorption process was endothermic, spontaneous and physical in nature. LVAC was shown to be an ultrahighly efficient sorbent for removal of 2,4-D from groundwater, which could be also recycled and reused.

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Use of bentonite to control the release of copper from contaminated soils

Soil Research ◽

10.1071/sr07079 ◽

2007 ◽

Vol 45 (8) ◽

pp. 618 ◽

Cited By ~ 45

Author(s):

Wanting Ling ◽

Qing Shen ◽

Yanzheng Gao ◽

Xiaohong Gu ◽

Zhipeng Yang

Keyword(s):

Heavy Metals ◽

Sorption Capacity ◽

Contaminated Soils ◽

Montmorillonite Clay ◽

Maximum Sorption Capacity ◽

Maximum Sorption ◽

Wide Ph Range ◽

Ph Dependent ◽

Ph Range ◽

Soil Ageing

A decrease in release and availability of heavy metals in soil has been of worldwide interest in recent years. Bentonite is a type of expandable montmorillonite clay, and has strong sorption for heavy metals. In this work, the control of amended bentonite on the release of copper (Cu2+) from spiked soils was investigated using a batch equilibrium technique. Sorption of Cu by bentonite was pH-dependent, and could be well described using the Langmiur model. Maximum sorption capacity of the bentonite used in this study was 5.4 mg/g, which was much greater than soils reported in the literature. The extent of Cu2+ release from spiked soils was correlated with slurry concentrations, pH, and soil ageing process. In all cases, the amendment of bentonite was observed to effectively decrease the release of Cu2+ from soils. The apparent aqueous concentrations of Cu2+ released from soils devoid of bentonite treatment were 113–1160% higher than those from the soils amended with bentonite. Moreover, the magnitude of Cu2+ release decreased with increasing amount of bentonite added to soils. The bentonite added was more effective in retaining Cu2+ in sorbents for aged contaminated soils. Such enhanced retention resulting from the presence of bentonite was observed within a wide pH range from 2.5 to 7.0. Bentonite, as one of the most abundant minerals in soils, is regarded to improve the soil overall quality. The results obtained from this work provide useful information on utilisation of bentonite to control the release of heavy metals from contaminated soils.

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Arsenic removal from groundwater by Anjili tree sawdust impregnated with ferric hydroxide and activated alumina

Water Science & Technology Water Supply ◽

10.2166/ws.2015.119 ◽

2015 ◽

Vol 16 (1) ◽

pp. 115-127 ◽

Cited By ~ 4

Author(s):

P. Dhanasekaran ◽

P. M. Satya Sai ◽

C. Anand Babu ◽

R. Krishna Prabhu ◽

K. K. Rajan

Keyword(s):

Arsenic Removal ◽

Heart Diseases ◽

Ferric Hydroxide ◽

Sorption Kinetics ◽

Activated Alumina ◽

Maximum Sorption Capacity ◽

Maximum Sorption ◽

Freundlich Adsorption Isotherm ◽

Pseudo Second Order ◽

Removal Of Arsenic

Arsenic is a toxic element found naturally in groundwater. Due to its carcinogenicity, risk for heart diseases and diabetes, arsenic needs to be removed from groundwater for potable application. ‘Anjili’ tree sawdust was chemically modified with ferric hydroxide and activated alumina (SFAA) and used as an adsorbent for the removal of arsenic from groundwater. The adsorbent was characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) to study the pore structure and surface functional groups. Effect of contact time, initial concentration, pH, particle size and temperature was studied. Arsenic adsorbed by SFAA followed Freundlich adsorption isotherm. Maximum sorption of arsenic by SFAA adsorbent occurred at pH 6.5. Arsenic sorption kinetics followed a pseudo-second-order model. The maximum sorption capacity at 303 K was found to be 54.32 mg/g for As(III) and 77.60 mg/g for As(V). Interference of other ions on the adsorption was in the order of PO43− > SO42− > HCO3− > NO3−.

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Use of aminated hulls of sunflower seeds for the removal of anionic dyes from aqueous solutions

International Journal of Environmental Science and Technology ◽

10.1007/s13762-019-02536-8 ◽

2019 ◽

Vol 17 (3) ◽

pp. 1211-1224 ◽

Cited By ~ 4

Author(s):

T. Jóźwiak ◽

U. Filipkowska ◽

S. Brym ◽

L. Kopeć

Keyword(s):

Sorption Capacity ◽

Textile Industry ◽

Sunflower Seed ◽

Freundlich Isotherm ◽

Sorption Kinetics ◽

Reactive Black 5 ◽

Anionic Dyes ◽

Maximum Sorption Capacity ◽

Maximum Sorption

Abstract In this study, we analyzed the effectiveness of sorption of dyes popular in the textile industry (Reactive Black 5, Reactive Yellow 84, Acid Yellow 23, and Acid Red 18) on aminated and non-aminated seed hulls of common sunflower (Helianthus annuus L.). The scope of the study included: determination of the effect of pH on dye sorption effectiveness, sorption kinetics analyses (sorption equilibrium time, pseudo-first-order/pseudo-second-order model, intramolecular diffusion model), and determination of the maximum sorption capacity against dyes (Langmuir/Freundlich isotherm). The sorbent was subjected to the FTIR analysis. The sorption capacity of the aminated sunflower seed hulls against reactive dyes RB5 and RY84 accounted for 51.02 mg/g and 63.27 mg/g, respectively, and was higher by 1665% (17.6 times higher) and 1425% (15.3 times higher) compared to that of non-modified hulls. In the case of acidic dyes, Acid Yellow 23 and Acid Red 18, the sorption capacity of the aminated sunflower seed hulls reached 44.78 mg/g and 42.19 mg/g, respectively, and was higher by 1881% (19.8 times higher) and 2284% (23.8 times higher), respectively, compared to the non-modified hulls.

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Adsorption of CuCl2 on Mg-Al HTlc: Effect of EDTA and Addition Sequences

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.573-574.150 ◽

2012 ◽

Vol 573-574 ◽

pp. 150-154

Author(s):

Yun Bo Zang ◽

Nai Ying Wu

Keyword(s):

Aqueous Solutions ◽

Sorption Capacity ◽

Contact Time ◽

Room Temperature ◽

Copper Ions ◽

Sorption Process ◽

Langmuir Model ◽

Maximum Sorption Capacity ◽

Maximum Sorption ◽

Pseudo Second Order

In this study, removal of copper ions from aqueous solutions by synthetic Mg-Al-HTlc was investigated as a function of contact time, EDTA and addition sequences at room temperature. It is found that HTlc could reduced copper ions concentration effectively. The kinetics closely fit pseudo-second order kinetics with necessary time 9 h to reach equilibrium. The sorption process followed langmuir model. The maximum sorption capacity calculated was found to be 39.4 mg/g. The presence of EDTA and addition sequences could affect sorption of Cu(II) onto HTlc.

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Features of adsorption processes for wastewater treatment from zinc ions

Environmental Problems ◽

10.23939/ep2021.02.064 ◽

2021 ◽

Vol 6 (2) ◽

pp. 64-68

Author(s):

Ihor Petrushka ◽

◽

Oksana Bratus ◽

Kateryna Petrushka ◽

◽

...

Keyword(s):

Sorption Process ◽

Adsorption Properties ◽

Zinc Ions ◽

Optimal Conditions ◽

Solid Complex ◽

Monomolecular Layer ◽

Maximum Sorption Capacity ◽

Maximum Sorption ◽

Adsorption Processes ◽

Langmuir And Freundlich Models

The results of adsorption properties of complex natural sorbents in relation to the neutralization of zinc ions from wastewater are presented. The adsorption isotherm of Zn2+ ions on complex sorbents (clinoptilolite-shungite) (1:1) according to Langmuir and Freundlich models is constructed, the type of adsorption isotherms according to S. Brunauer classification is established. The value of the maximum sorption capacity of Gmax complex sorbents for Zn2+ ions is calculated. The peculiarities of the sorption process of zinc ions with the formation of a monomolecular layer based on the calculated coefficients of the Langmuir and Freundlich were found. The optimal conditions for the dependence of the degree of absorption of Zn2+ ions by complex sorbents on the duration of the sorption process are determined. The ratio "solid (complex sorbent) - liquid" was determined experimentally.

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Sorption studies of Cr(VI) from aqueous solution using bio-char as an adsorbent

Water Science & Technology ◽

10.2166/wst.2014.143 ◽

2014 ◽

Vol 69 (11) ◽

pp. 2265-2271 ◽

Cited By ~ 15

Author(s):

A. H. M. G. Hyder ◽

Shamim A. Begum ◽

Nosa O. Egiebor

Keyword(s):

Aqueous Solution ◽

Low Cost ◽

Treatment Plant ◽

Sorption Process ◽

Sorption Kinetics ◽

Synthetic Wastewater ◽

Order Kinetic ◽

Water And Wastewater Treatment ◽

Maximum Sorption Capacity ◽

Kinetics And Isotherms

The characteristics of sorption of hexavalent chromium (Cr(VI)) onto bio-char derived from wood chips (spruce, pine, and fir) were evaluated as a function of pH, initial Cr(VI) concentration and bio-char dosage using synthetic wastewater in batch tests. The initial Cr(VI) concentrations were varied between 10 and 500 mg/L to investigate equilibrium, kinetics, and isotherms of the sorption process. About 100% of Cr(VI) was removed at pH 2 with initial Cr(VI) concentration of 10 mg/L using 4 g of bio-char after 5 hours of sorption reaction. The maximum sorption capacity of the bio-char was 1.717 mg/g for an initial Cr(VI) concentration of 500 mg/L after 5 hours. The sorption kinetics of total Cr onto bio-char followed the second-order kinetic model. The Langmuir isotherm model provided the best fit for total Cr sorption onto bio-char. The bio-char used is a co-product of a down draft gasifier that uses the derived syngas to produce electricity. Bio-char as a low cost adsorbent demonstrated promising results for removal of Cr(VI) from aqueous solution. The findings of this study would be useful in designing a filtration unit with bio-char in a full-scale water and wastewater treatment plant for the Cr(VI) removal from contaminated waters.

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A Highly Efficient Environmental-Friendly Adsorbent Based on Schiff Base for Removal of Cu(II) from Aqueous Solutions: A Combined Experimental and Theoretical Study

Molecules ◽

10.3390/molecules26175164 ◽

2021 ◽

Vol 26 (17) ◽

pp. 5164

Author(s):

Said Tighadouini ◽

Othmane Roby ◽

Smaail Radi ◽

Zouhair Lakbaibi ◽

Rafik Saddik ◽

...

Keyword(s):

Heavy Metals ◽

Schiff Base ◽

High Selectivity ◽

Theoretical Study ◽

X Ray ◽

Maximum Sorption Capacity ◽

Removal Of Heavy Metals ◽

Maximum Sorption ◽

Spectroscopy Studies ◽

Adsorption Desorption

Removal of heavy metals from drinking water sources and rivers is of strategic health importance and is essential for sustainable ecosystem development, in particular in polluted areas around the globe. In this work, new hybrid inorganic-organic material adsorbents made of ortho- (Si-o-OR) or para-Schiff base silica (Si-p-OR) were synthesized and characterized in depth. These hybrid adsorbents show a high selectivity to Cu(II), even in the presence of competing heavy metals (Zn(II), Cd(II), and Pb(II)), and also demonstrate great reusability after five adsorption-desorption cycles. Maximum sorption capacity for Cu(II) was found for Si-o-OR (79.36 mg g−1) and Si-p-OR (36.20 mg g−1) in no less than 25 min. Energy dispersive X-ray fluorescence and Fourier transform-infrared spectroscopy studies demonstrate that this uptake occurs due to a chelating effect, which allows these adsorbents to trap Cu(II) ions on their surfaces; this result is supported by a theoretical study for Si-o-OR. The new adsorbents were tested against real water samples extracted from two rivers from the Oriental region of Morocco.

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Boron Removal by Sorption on Modified Chitosan Hydrogel Beads

Materials ◽

10.3390/ma14195646 ◽

2021 ◽

Vol 14 (19) ◽

pp. 5646

Author(s):

Joanna Kluczka ◽

Gabriela Dudek ◽

Wojciech Pudło ◽

Alicja Kazek-Kęsik ◽

Roman Turczyn

Keyword(s):

Aqueous Media ◽

Freundlich Isotherm ◽

Sorption Kinetics ◽

Isotherm Models ◽

Isotherm Equation ◽

Hydrogel Beads ◽

Maximum Sorption Capacity ◽

Modified Chitosan ◽

Maximum Sorption ◽

Naoh Solution

An excess concentration of boron in irrigation and drinking water can negatively affect the yield of plants and the human nervous system, respectively. To meet the recommended levels, hybrid biosorbent hydrogel beads based on chitosan and manganese (II-IV) were employed for the removal of boron from aqueous media. The results showed that the biosorbent effectively removed boric acid from the aqueous medium at neutral pH over a sorption time of 2 h and the liquid/hydrogel ratio of 20 mL/g, achieving a maximum sorption capacity near 190 mg/g. The modeling of the sorption equilibrium data indicated that the Freundlich isotherm equation gave the best fit out of the isotherm models examined. A pseudo-second-order model was found to best describe the sorption kinetics. The favorable attachment of manganese to the chitosan structure enabled the sorption of boron and was confirmed by FTIR, RS, XRD, SEM and ICP-OES methods. Boron desorption from the spent biosorbent was successfully achieved in three cycles using a NaOH solution. In general, the results of this research indicate that this method is one of the possibilities for improving water quality and may contribute to reducing pollution of the aquatic environment.

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