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

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 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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An application research for near-surface repository of strontium-90 sorption kinetic model on mudrocks

Kerntechnik ◽

10.1515/kern-2021-1021 ◽

2021 ◽

Vol 86 (6) ◽

pp. 404-410

Author(s):

Y. Shi ◽

W. Chen ◽

H. Lin ◽

Z. Gao ◽

B. Yang ◽

...

Keyword(s):

Kinetic Model ◽

Sorption Capacity ◽

Rate Constant ◽

Local Environment ◽

Sorption Process ◽

Sorption Kinetic ◽

Near Surface ◽

Maximum Sorption Capacity ◽

Groundwater Environment ◽

Maximum Sorption

Abstract In this study,90Sr was used as the test radionuclide to characterize the sorption kinetics and effects of initial 90Sr activity and remaining 90Sr in solid concentration were simulated for a near-surface repository. The study focused on the sorption characteristics of radionuclides in unsaturated groundwater environment (or vadose zone) is the important information for investigating the near-surface disposal of intermediate and low-level radioactive waste (ILLW). Moreover, the 90Sr sorption experiments reached equilibrium within 56 h, which fit to the first order sorption kinetic model, and the remaining 90Sr in mudrock samples showed obvious sorption equilibrium hysteresis, which fit to the second order sorption kinetic model. Before reaching the maximum sorption capacity, the sorption rate constant increases with 90Sr increasing; the distribution coefficient (Kd) of 56 h decreases with the remaining 90Sr decreasing. In addition, it showed that the slow sorption process dominated before the sorption reaches equilibrium. In fact, a reliable safety assessment methodology for on-going near-surface repository required a lot of the radionuclides parameters with local environment including the radionuclides sorption/desorption rate constant and maximum sorption capacity.

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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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THE INFLUENCE OF CHITOSAN FLAKE DEACETYLATION DEGREE ON ORTHOPHOSPHATE SORPTION EFFICIENCY FROM AQUEOUS SOLUTIONS

Progress on Chemistry and application of Chitin and its Derivatives ◽

10.15259/pcacd.23.003 ◽

2018 ◽

Vol XXIII ◽

pp. 33-44 ◽

Cited By ~ 1

Author(s):

Paula Bugajska ◽

Urszula Filipkowska ◽

Tomasz Jóźwiak ◽

Małgorzata Kuczajowska-Zadrożna

Keyword(s):

Aqueous Solutions ◽

Sorption Capacity ◽

Ph Value ◽

Sorption Process ◽

Phosphorus Compounds ◽

Desorption Process ◽

Maximum Sorption Capacity ◽

Deacetylation Degree ◽

Maximum Sorption ◽

Sorption From Aqueous Solutions

The article presents the effectiveness of orthophosphate sorption from aqueous solutions depending on the deacetylation degree of chitosan flakes. The first stage of the research was to determine the pH value at which the sorption process was the most effective (from the pH range 2–11). In the second stage, research was carried out to determine the maximum sorption capacities of chitosan with deacetylation degrees of 75%, 85% and 90% in relation to PO43-. The highest effectiveness of orthophosphate removal on chitosan, regardless of its deacetylation degree, was obtained at pH 4. At pH 2 and 3, the chitosan flakes dissolved. This study showed that the sorption effectiveness of phosphorus compounds depends on the deacetylation degree of chitosan. Along with the increase in deacetylation degree, the sorption capacity of chitosan also increases in relation to orthophosphates. It is related to the higher number of amino groups in the structure of chitosan, which are responsible for the sorption of pollutants in the form of anions. The maximum sorption capacity of chitosan-DD = 75% in relation to biogen was 5.13 mg/g, chitosan-DD = 85% was 5.65 mg/g, and chitosan-DD = 90% was 5.91 mg/g. After 60 minutes, the desorption process had begun and was most likely caused by an increase in the pH of the solution. Due to chitosan's ability to neutralise the sample and the associated risk of desorption, the time of sorbent contact with sewage cannot be longer than 60 minutes.

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Preparation of chitosan functionalized polyamidoamine for the separation of trivalent lanthanides from acidic waste solution

Radiochimica Acta ◽

10.1515/ract-2018-3022 ◽

2019 ◽

Vol 107 (5) ◽

pp. 415-422

Author(s):

S. Pahan ◽

S. Panja ◽

D. Banerjee ◽

P. S. Dhami ◽

J. S. Yadav ◽

...

Keyword(s):

Sorption Capacity ◽

Water Solution ◽

Sorption Process ◽

Waste Solution ◽

Maximum Sorption Capacity ◽

Increasing Trend ◽

Maximum Sorption ◽

Langmuir Isotherm Model ◽

Kinetics Of ◽

Solution Kinetics

Abstract The manuscript deals with the sorption of Am(III) and Eu(III) from pH medium using chitosan functionalized with dendrimer like polyamidoamine (PAMAM) polymers up to third generation. The PAMAM polymers were introduced into chitosan by two step processes and were characterized by various instrumental techniques like FTIR, XRD, TG-DTA. The sorption process was highly pH dependent for both Am(III) and Eu(III) with increasing trend for higher pH of the solution. Kinetics of equilibration was found to be fast with equilibrium attained in 10 min for both the metal ions. Pseudo 2nd order kinetics mechanism was found to be followed for both Am(III) and Eu(III). The sorption process of Eu(III) was found to fit the Langmuir isotherm model with maximum sorption capacity of 6.01 mg/g. There was no effect on the generation of PAMAM Dendron on the efficiency, kinetics or sorption capacity for Am(III) as well as Eu(III). The synthesized different generation of PAMAM functionalized chitosan is a promising material for removal of actinides and lanthanides from waste water solution.

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

The Scientific World JOURNAL ◽

10.1155/2017/2675897 ◽

2017 ◽

Vol 2017 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Huemantzin Balan Ortiz-Oliveros ◽

Rosa María Flores-Espinosa ◽

Eduardo Ordoñez-Regil ◽

Suilma Marisela Fernández-Valverde

Keyword(s):

Heavy Metals ◽

Surface Roughness ◽

Kinetic Constant ◽

Surface Acidity ◽

Sorption Process ◽

Sorption Kinetics ◽

Acidity Constants ◽

Maximum Sorption Capacity ◽

Maximum Sorption ◽

Titanium Pyrophosphate

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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Equilibrium Sorption Studies of Basic Blue-9 Dye from Aqueous Medium Using Activated Carbon Produced from Water Hyacinth (Eichornia Crassipes)

Journal of Nepal Chemical Society ◽

10.3126/jncs.v29i0.9254 ◽

2013 ◽

Vol 29 ◽

pp. 67-74 ◽

Cited By ~ 2

Author(s):

Timi Tarawou ◽

D. Wankasi ◽

Michael Horsfall Jnr

Keyword(s):

Activated Carbon ◽

Sorption Capacity ◽

Water Hyacinth ◽

Diffusion Constant ◽

Chemical Society ◽

Sorption Process ◽

Raw Material ◽

Maximum Sorption Capacity ◽

Freundlich Isotherms ◽

Micropore Diffusion

The study shows that water hyacinth could be used as novel raw material for the production of effective activated carbon for the adsorption (removal) of Basic Blue- 9 dye from aqueous solution. Optimum removal of 86% dye was obtained which decreased to 62% with an increase in concentration from 50 to 300mg/l, though sorption capacity was found to increase with an increase in concentration. Both Langmuir and Freundlich isotherms were suitable for describing the experimental data in this study with high regression coefficients (R2) of 0.9852 and 0.9905 respectively. The Langmuir maximum sorption capacity (qm) was found to be 421mg/g. It was further observed that the intensity of adsorption, n, was found to be 1.84 which shows that the sorption process was favourable. The equilibrium parameter, RL, value of 0.138 also shows that the adsorption of Basic Blue-9 dyes onto the activated carbon was favourable. The macropore and micropore diffusion constants show that the rate limiting step is the micropore diffusion stage since the micropore diffusion constant (Kid2) value of 0 is lower than the macropore diffusion constant (Kid) value of 0.2543, thus the rate of micropore diffusion is the slower step and the rate determining step. The study also showed that the sorption process was predominantly controlled by intra-particle diffusion, though film diffusion also played a significant role.DOI: http://dx.doi.org/10.3126/jncs.v29i0.9254Journal of Nepal Chemical Society Vol. 29, 2012 Page: 67-74 Uploaded date: 12/5/2013

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Природные материалы для сорбционной очистки хром- и кадмийсодержащих инфильтратов полигонов ТБО

Vodosnabzhenie i sanitarnaia tehnika ◽

10.35776/mnp.2019.12.02 ◽

2019 ◽

pp. 13-19

Author(s):

A. Safonov ◽

N. Andriushchenko ◽

N. Popova ◽

K. Boldyrev

Keyword(s):

Sorption Capacity ◽

Electron Acceptors ◽

Bacterial Cells ◽

Maximum Sorption Capacity ◽

Sorption Material ◽

Maximum Sorption ◽

Properties Of Materials ◽

Solid Waste Landfills ◽

Sorption Characteristics

Проведен анализ сорбционных характеристик природных материалов (вермикулит, керамзит, перлит, цеолит Трейд ) при очистке кадмий- и хромсодержащих сточных вод с высокой нагрузкой по ХПК. Установлено, что цеолит обладает максимальными сорбционными характеристиками для Cd и Cr и наименьшим биологическим обрастанием. При использовании вермикулита и керамзита или смесей на их основе можно ожидать увеличения сорбционной емкости для Cd и Сr при микробном обрастании, неизбежно происходящем в условиях контакта с водами, загрязненными органическими соединениями и биогенами. При этом биообрастание может повысить иммобилизационную способность материалов для редоксзависимых металлов за счет ферментативных ресурсов бактериальных клеток, использующих их в качестве акцепторов электронов. Эффект микробного обрастания разнонаправленно изменял параметры материалов: для Cr в большинстве случаев уменьшение и для Cd значительное увеличение. При этом дополнительным эффектом иммобилизации Cr является его биологическое восстановление биопленками. Варьируя состав сорбционного материала, можно подбирать смеси, оптимально подходящие для очистки вод инфильтратов с полигонов твердых бытовых отходов с высокой нагрузкой по ХПК и биогенным элементам как при использовании in situ, так и в системах на поверхности.The analysis of the sorption characteristics of natural materials (vermiculite, expanded clay, perlite, Trade zeolite) during the purification of cadmium and chromium-containing leachate with a high COD load was carried out. It was determined that zeolite had the maximum sorption capacity for Cd and Cr and the lowest biological fouling. When using vermiculite and expanded clay or mixtures on their basis, one can expect an increase in the sorption capacity for Cd and Cr during microbial fouling that inevitably occurs during contacting with water polluted with organic compounds and nutrients. In this case biofouling can increase the immobilization properties of materials for redox-dependent metals due to the enzymatic resources of bacterial cells that use them as electron acceptors. The effect of microbial fouling changed the parameters of materials in different directions: for Cr, in most cases, downward, and for Cd, significantly upward. Moreover, chromium biological recovery by biofilms is an additional effect of immobilization. Varying the composition of the sorption material provides for selecting mixtures that are optimally suitable for the purification of leachates from solid waste landfills with high COD and nutrients load, both when used in situ and in surface systems.

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Phosphate Removal Using Polyethylenimine Functionalized Silica-Based Materials

Sustainability ◽

10.3390/su13031502 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1502

Author(s):

Maria Xanthopoulou ◽

Dimitrios Giliopoulos ◽

Nikolaos Tzollas ◽

Konstantinos S. Triantafyllidis ◽

Margaritis Kostoglou ◽

...

Keyword(s):

Sorption Capacity ◽

Removal Rate ◽

Phosphate Concentration ◽

Phosphate Removal ◽

Equilibrium Studies ◽

Maximum Sorption Capacity ◽

Algae Blooms ◽

Maximum Sorption ◽

Phosphate Anions ◽

Adsorbent Dose

In water and wastewater, phosphate anions are considered critical contaminants because they cause algae blooms and eutrophication. The present work aims at studying the removal of phosphate anions from aqueous solutions using silica particles functionalized with polyethylenimine. The parameters affecting the adsorption process such as pH, initial concentration, adsorbent dose, and the presence of competitive anions, such as carbonate, nitrate, sulfate and chromate ions, were studied. Equilibrium studies were carried out to determine their sorption capacity and the rate of phosphate ions uptake. The adsorption isotherm data fitted well with the Langmuir and Sips model. The maximum sorption capacity was 41.1 mg/g at pH 5, which decreased slightly at pH 7. The efficiency of phosphate removal adsorption increased at lower pH values and by increasing the adsorbent dose. The maximum phosphate removal was 80% for pH 5 and decreased to 75% for pH 6, to 73% for pH 7 and to 70% for pH 8, for initial phosphate concentration at about 1 mg/L and for a dose of adsorbent 100 mg/L. The removal rate was increased with the increase of the adsorbent dose. For example, for initial phosphate concentration of 4 mg/L the removal rate increased from 40% to 80% by increasing the dose from 0.1 to 2.0 g/L at pH 7. The competitive anions adversely affected phosphate removal. Though they were also found to be removed to a certain extent. Their co-removal provided an adsorbent which might be very useful for treating waters with low-level multiple contaminant occurrence in natural or engineered aquatic systems.

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