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12 pages, 1662 KiB

Open AccessArticle

Adsorption of Ag (I) Ions at the Zirconium Phosphate/KNO₃ Aqueous Solution Interface

by Władysław Janusz, Ewa Skwarek, Volodymyr Sydorchuk and Svitlana Khalameida

Materials 2022, 15(14), 5050; https://doi.org/10.3390/ma15145050 - 20 Jul 2022

Cited by 2 | Viewed by 1558

Abstract

The paper presented the mechanical (MChT), microwave (MWT), and hydrothermal (HTT) methods of zirconium phosphate samples modification in order to improve its adsorption affinity for the Ag (I) ions. The FTIR studies proved that the modification of both gel and xerogel samples with [...] Read more.

The paper presented the mechanical (MChT), microwave (MWT), and hydrothermal (HTT) methods of zirconium phosphate samples modification in order to improve its adsorption affinity for the Ag (I) ions. The FTIR studies proved that the modification of both gel and xerogel samples with the ultrasonic microwaves causes an increase in the concentration of phosphate groups on the surface of MWT-modified zirconium phosphate: the isoelectric point pHiep = 2.2–2.9 for these samples against 3.9 for the initial sample and pKa2 values were 4.7–5.6 and 6.3, respectively. As resulting from the Ag⁺ ion adsorption studies, the MWT treatment of zirconium phosphate samples caused the greatest affinity of Ag⁺ ions for the surface of MWT zirconium phosphate. Compared with the initial ZrP sample, the shift of the Ag (I) ion adsorption edge towards lower pH values was observed, e.g., with adsorption of Ag (I) ions from the solution with the initial concentration of 1 µmol/dm³ for the initial ZrP sample pH50% = 3.2, while for the sample MWT ZrPxero pH50% = 2.6. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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14 pages, 3304 KiB

Open AccessArticle

Effects of Moisture on NH₃Capture Using Activated Carbon and Acidic Porous Polymer Modified by Impregnation with H₃PO₄: Sorbent Material Characterized by Synchrotron XRPD and FT-IR

by Chu-Chin Hsieh, Jyong-Sian Tsai and Jen-Ray Chang

Materials 2022, 15(3), 784; https://doi.org/10.3390/ma15030784 - 20 Jan 2022

Cited by 6 | Viewed by 2173

Abstract

The performances of reactive adsorbents, H₃PO₄/C (activated carbon) and H₃PO₄/A (Amberlyst 35), in removing NH₃ from a waste-gas stream were investigated using a breakthrough column. Accelerated aging tests investigated the effects of the water [...] Read more.

The performances of reactive adsorbents, H₃PO₄/C (activated carbon) and H₃PO₄/A (Amberlyst 35), in removing NH₃ from a waste-gas stream were investigated using a breakthrough column. Accelerated aging tests investigated the effects of the water content on the performance of the adsorbents. Results of breakthrough tests show that the adsorption capacity greatly decreased with the drying time of H₃PO₄/C preparation. Synchrotron XRPD indicated increased amorphous phosphorus species formation with drying time. Nitrogen adsorption-desorption isotherms results further suggested that the evaporation of water accommodated in macropores decreases adsorption capacity besides the formation of the amorphous species. Introducing water moisture to the NH₃ stream increases the adsorption capacity concomitant with the conversion of some NH₄H₂PO₄ to (NH₄)₂HPO₄. Due to the larger pore of cylindrical type and more hydrophilic for acidic porous polymer support, as opposed to slit-type for the activated carbon, the adsorption capacity of H₃PO₄/A is about 3.4 times that of H₃PO₄/C. XRPD results suggested that NH₃ reacts with aqueous H₃PO₄ to form NH₄H₂PO_4, and no significant macropore-water evaporation was observed when acidic porous polymer support was used, as evidenced by N₂ isotherms characterizing used H₃PO₄/A. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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20 pages, 2877 KiB

Open AccessArticle

Enhanced Defluoridation of Water Using Zirconium—Coated Pumice in Fixed-Bed Adsorption Columns

by Wondwosen Sime Geleta, Esayas Alemayehu and Bernd Lennartz

Materials 2021, 14(20), 6145; https://doi.org/10.3390/ma14206145 - 16 Oct 2021

Cited by 6 | Viewed by 2834

Abstract

Millions of people across the globe suffer from health issues related to high fluoride levels in drinking water. The purpose of this study was to test modified pumice as an adsorbent for the purification of fluoride-containing waters. The adsorption of fluoride onto zirconium-coated [...] Read more.

Millions of people across the globe suffer from health issues related to high fluoride levels in drinking water. The purpose of this study was to test modified pumice as an adsorbent for the purification of fluoride-containing waters. The adsorption of fluoride onto zirconium-coated pumice (Zr–Pu) adsorbent was examined in fixed-bed adsorption columns. The coating of zirconium on the surface of VPum was revealed by X-ray diffractometer (XRD), Inductively coupled plasma-optical emission spectroscopy (ICP-EOS), and X-ray fluorescence (XRF) techniques. The degree of surface modification with the enhanced porosity of Zr–Pu was evident from the recorded scanning electron microscope (SEM) micrographs. The Brunauer-Emmett-Teller (BET) analysis confirmed the enhancement of the specific surface area of VPum after modification. The Fourier transform infrared (FTIR) examinations of VPum and Zr–Pu before and after adsorption did not reveal any significant spectrum changes. The pH drift method showed that VPum and Zr–Pu have positive charges at pH_PZC lower than 7.3 and 6.5, respectively. Zr–Pu yielded a higher adsorption capacity of 225 mg/kg (2.05 times the adsorption capacity of VPum: 110 mg/kg), at pH = 2 and volumetric flow rate (Q_O) of 1.25 mL/min. Breakthrough time increases with decreasing pH and flow rate. The experimental adsorption data was well-matched by the Thomas and Adams-Bohart models with correlation coefficients (R²) of ≥ 0.980 (Zr–Pu) and ≥ 0.897 (VPum), confirming that both models are suitable tools to design fixed-bed column systems using volcanic rock materials. Overall, coating pumice with zirconium improved the defluoridation capacity of pumice; hence, a Zr–Pu-packed fixed-bed can be applied for defluoridation of excess fluoride from groundwater. However, additional investigations on, for instance, the influences of competing ions are advisable to draw explicit conclusions. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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17 pages, 2887 KiB

Open AccessArticle

Preparation and Characterization of Physicochemical Properties of Spruce Cone Biochars Activated by CO₂

by Katarzyna Jedynak and Barbara Charmas

Materials 2021, 14(14), 3859; https://doi.org/10.3390/ma14143859 - 10 Jul 2021

Cited by 24 | Viewed by 3792

Abstract

In this study the pyrolysis of Norway spruce cones, a lignocellulosic biomass was made. The biochar product was obtained by means of the physical activation method. CO₂ was used as the activating gas. The surface properties of biochars were characterized by the [...] Read more.

In this study the pyrolysis of Norway spruce cones, a lignocellulosic biomass was made. The biochar product was obtained by means of the physical activation method. CO₂ was used as the activating gas. The surface properties of biochars were characterized by the nitrogen adsorption/desorption isotherms, scanning electron microscopy (SEM/EDS), X-ray fluorescence energy dispersion spectroscopy (ED-XRF), thermal analysis (TGA/DTA), infrared spectroscopy (ATR FT-IR), Raman spectroscopy and the Boehm’s titration method as well as the point of zero charge (pH_pzc). The adsorption capacity and the possibility of ammonia desorption (TPD) were also examined. It has been shown that spruce cones can be successfully used as a cheap precursor of well-developed surface biochars, characterized by a large pore volume and good sorption properties. All obtained activated biochars exhibit a largely microporous structure and an acidic character surface. The investigated activated materials have the specific surface areas from 112 to 1181 m² g⁻¹. The maximum NH₃ adsorption capacity of the activated biochar was determined to be 5.18 mg g⁻¹ (88.22 mmol g⁻¹) at 0 °C. These results indicate the applicability of spruce cones as a cheap precursor for the sustainable production of the cost-effective and environmentally friendly biochar adsorbent. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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16 pages, 2822 KiB

Open AccessArticle

Adsorption of the Tartrate Ions in the Hydroxyapatite/Aqueous Solution of NaCl System

by Władysław Janusz and Ewa Skwarek

Materials 2021, 14(11), 3039; https://doi.org/10.3390/ma14113039 - 3 Jun 2021

Cited by 5 | Viewed by 2228

Abstract

The research on the interaction of tartrate ions with the surface of hydroskyapatite was presented, including the measurements of the kinetics of tartrate ion adsorption and tartrate ion adsorption as a function of pH. The adsorption of tartrate ions was calculated from the [...] Read more.

The research on the interaction of tartrate ions with the surface of hydroskyapatite was presented, including the measurements of the kinetics of tartrate ion adsorption and tartrate ion adsorption as a function of pH. The adsorption of tartrate ions was calculated from the loss of tartrate concentration in the solution as measured by a radioisotope method using C-14 labeled tartaric acid. In order to explain the mechanism of interaction of tartrate ions with hydroxyapatite, supplementary measurements were carried out, i.e., potentiometric measurements of the balance of released/consumed ions in the hydroxyapatite/electrolyte solution system, zeta potential measurements, FTIR spectrophotometric measurements and the hydroxyapatite crystal structure and particle size distribution were characterized. It was found that the adsorption of tartrate ions occurs as a result of the exchange of these ions with hydroxyl, phosphate and carbonate ions. Replacing the ions with the abovementioned tartrate ions leads to the appearance of a negative charge on the surface of the hydroxapatite. On the basis of XRD study and particle size distribution, a decrease in the size of crystallites and the diameter of hydroxyapatite particles in contact with a solution of 0.001 mol/dm³ of tartaric acid was found. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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10 pages, 2112 KiB

Open AccessArticle

Uptake of Radionuclides ⁶⁰Co, ¹³⁷Cs, and ⁹⁰Sr with α-Fe₂O₃ and Fe₃O₄ Particles from Aqueous Environment

by Natalya V. Efimova, Alla P. Krasnopyorova, Galina D. Yuhno, Dmitry S. Sofronov and Mirosław Rucki

Materials 2021, 14(11), 2899; https://doi.org/10.3390/ma14112899 - 28 May 2021

Cited by 10 | Viewed by 2365

Abstract

In the paper, investigation results of the uptake efficiency of radionuclides ⁶⁰Co, ⁹⁰Sr, and ¹³⁷Cs dissolved in water onto iron oxides α-Fe₂O₃ and Fe₃O₄ are presented. It was found that sorption efficiency increased for [...] Read more.

In the paper, investigation results of the uptake efficiency of radionuclides ⁶⁰Co, ⁹⁰Sr, and ¹³⁷Cs dissolved in water onto iron oxides α-Fe₂O₃ and Fe₃O₄ are presented. It was found that sorption efficiency increased for higher pH values. Independent of the oxide nature, the uptake characteristics are the best toward ⁶⁰Co and the worst toward ¹³⁷Cs, forming the row as follows: ⁶⁰Co > ⁹⁰Sr > ¹³⁷Cs. The highest sorption ability at pH 9 was found for magnetite Fe₃O₄, which was 93%, 73%, and 26% toward ⁶⁰Co, ⁹⁰Sr, and ¹³⁷Cs, respectively, while the respective percentages for hematite α-Fe₂O₃ were 85%, 41%, and 18%. It was assumed that the main sorption mechanism was ion exchange. That may explain some decrease of the sorption efficiency in drinking water due to the interfering presence of magnesium and calcium cations. The obtained results indicated the feasibility of the tested sorbents and their merits, especially in terms of relatively high uptake coefficients, low costs, availability, and lack of toxicity. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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16 pages, 21820 KiB

Open AccessArticle

Adsorptive Removal of Phosphate from Aqueous Solutions Using Low-Cost Volcanic Rocks: Kinetics and Equilibrium Approaches

by Dereje Tadesse Mekonnen, Esayas Alemayehu and Bernd Lennartz

Materials 2021, 14(5), 1312; https://doi.org/10.3390/ma14051312 - 9 Mar 2021

Cited by 22 | Viewed by 4190

Abstract

The contamination of surface and groundwater with phosphate originating from industrial and household wastewater remains a serious environmental issue in low-income countries. Herein, phosphate removal from aqueous solutions was studied using low-cost volcanic rocks such as pumice (VPum) and scoria (VSco), obtained from [...] Read more.

The contamination of surface and groundwater with phosphate originating from industrial and household wastewater remains a serious environmental issue in low-income countries. Herein, phosphate removal from aqueous solutions was studied using low-cost volcanic rocks such as pumice (VPum) and scoria (VSco), obtained from the Ethiopian Great Rift Valley. Batch adsorption experiments were conducted using phosphate solutions with concentrations of 0.5 to 25 mg·L⁻¹ to examine the adsorption kinetic as well as equilibrium conditions. The experimental adsorption data were tested by employing various equilibrium adsorption models, and the Freundlich and Dubinin-Radushkevich (D-R) isotherms best depicted the observations. The maximum phosphate adsorption capacities of VPum and VSco were calculated and found to be 294 mg·kg⁻¹ and 169 mg·kg⁻¹, respectively. A pseudo-second-order kinetic model best described the experimental data with a coefficient of correlation of R² > 0.99 for both VPum and VSco; however, VPum showed a slightly better selectivity for phosphate removal than VSco. The presence of competitive anions markedly reduced the removal efficiency of phosphate from the aqueous solution. The adsorptive removal of phosphate was affected by competitive anions in the order: HCO₃⁻ >F⁻ > SO₄⁻² > NO₃⁻ > Cl⁻ for VPum and HCO₃⁻ > F⁻ > Cl⁻ > SO₄⁻² > NO₃⁻ for VSco. The results indicate that the readily available volcanic rocks have a good adsorptive capacity for phosphate and shall be considered in future studies as test materials for phosphate removal from water in technical-scale experiments. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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12 pages, 3723 KiB

Open AccessArticle

Interactions between Active Ingredient Ranitidine and Clay Mineral Excipients in Pharmaceutical Formulations

by Lijuan Wang, Xisen Wang, Libing Liao, Qingfeng Wu, Hui Yin and Zhaohui Li

Materials 2020, 13(23), 5558; https://doi.org/10.3390/ma13235558 - 6 Dec 2020

Cited by 4 | Viewed by 2230

Abstract

Excipients play an important role in pharmaceutical formulations. Many clay minerals, because of their large specific surface area and inert behaviour in reactions with active ingredients, are commonly used as excipients. In this study, the uptake of ranitidine (RT), the active ingredient of [...] Read more.

Excipients play an important role in pharmaceutical formulations. Many clay minerals, because of their large specific surface area and inert behaviour in reactions with active ingredients, are commonly used as excipients. In this study, the uptake of ranitidine (RT), the active ingredient of Zantac, on and released from palygorskite (Pal), kaolinite (Kao), and talc was evaluated under different physicochemical conditions. The results showed that the uptake of RT on these minerals was limited to the external surface areas only. Cation exchange and electrostatic interactions were responsible for the RT uptake on Pal and Kao, resulting in a monolayer sorption. In contrast, multilayer RT uptake was found on the talc surfaces. Under different desorbing conditions, significant amounts of sorbed RT remained on the solid surface after 5 h of desorption. The results suggest that the sorptive interactions between the active ingredients and the excipients may not be neglected in pharmaceutical formulations, should these minerals be used as additives and/or excipients. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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13 pages, 2729 KiB

Open AccessArticle

Effect of Pressure and Temperature on CO₂/CH₄ Competitive Adsorption on Kaolinite by Monte Carlo Simulations

by Guanxian Kang, Bin Zhang, Tianhe Kang, Junqing Guo and Guofei Zhao

Materials 2020, 13(12), 2851; https://doi.org/10.3390/ma13122851 - 25 Jun 2020

Cited by 19 | Viewed by 3071

Abstract

The adsorption of CO₂ and CO₂/CH₄ mixtures on kaolinite was calculated by grand canonical Monte Carlo (GCMC) simulations with different temperatures (283.15, 293.15, and 313.15 K) up to 40 MPa. The simulation results show that the adsorption amount of [...] Read more.

The adsorption of CO₂ and CO₂/CH₄ mixtures on kaolinite was calculated by grand canonical Monte Carlo (GCMC) simulations with different temperatures (283.15, 293.15, and 313.15 K) up to 40 MPa. The simulation results show that the adsorption amount of CO₂ followed the Langmuir model and decreased with an increasing temperature. The excess adsorption of CO₂ increased with an increasing pressure until the pressure reached 3 MPa and then decreased at different temperatures. The

S_{C O_{2} / C H_{4}}

decreased logarithmically with increasing pressure, and the

S_{C O_{2} / C H_{4}}

was lower with a higher temperature at the same pressure. The interaction energy between CO₂ and kaolinite was much higher than that between CH₄ and kaolinite at the same pressure. The interaction energy between the adsorbent and adsorbate was dominant, and that between CO₂ and CO₂ and between CH₄ and CH₄ accounted for less than 20% of the total interaction energy. The isothermal adsorption heat of CO₂ was higher than that of CH₄, indicating that the affinity of kaolinite to CO₂ was higher than that of CH₄. The strong adsorption sites of carbon dioxide on kaolinite were hydrogen, oxygen, and silicon atoms, respectively. CO₂ was not only physically adsorbed on kaolinite, but also exhibited chemical adsorption. In gas-bearing reservoirs, a CO₂ injection to displace CH₄ and enhance CO₂ sequestration and enhanced gas recovery (CS-EGR) should be implemented at a low temperature. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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27 pages, 6818 KiB

Open AccessArticle

Removal of Barium from Solution by Natural and Iron(III) Oxide-Modified Allophane, Beidellite and Zeolite Adsorbents

by Andre Baldermann, Yvonne Fleischhacker, Silke Schmidthaler, Katharina Wester, Manfred Nachtnebel and Stefanie Eichinger

Materials 2020, 13(11), 2582; https://doi.org/10.3390/ma13112582 - 5 Jun 2020

Cited by 22 | Viewed by 3626

Abstract

Efficient capture of barium (Ba) from solution is a serious task in environmental protection and remediation. Herein, the capacity and the mechanism of Ba adsorption by natural and iron(III) oxide (FeO) modified allophane (ALO), beidellite (BEI) and zeolite (ZEO) were investigated by considering [...] Read more.

Efficient capture of barium (Ba) from solution is a serious task in environmental protection and remediation. Herein, the capacity and the mechanism of Ba adsorption by natural and iron(III) oxide (FeO) modified allophane (ALO), beidellite (BEI) and zeolite (ZEO) were investigated by considering the effects of contact time, temperature, pH, Ba²⁺ concentration, adsorbent dosage, the presence of competitive ions and adsorption–desorption cycles (regenerability). Physicochemical and mineralogical properties of the adsorbents were characterized by XRD, FTIR, SEM with EDX and N₂ physisorption techniques. The Ba²⁺ adsorption fitted to a pseudo-first-order reaction kinetics, where equilibrium conditions were reached within <30 min. BEI, ALO and ZEO with(out) FeO-modification yielded removal efficiencies for Ba²⁺ of up to 99.9%, 97% and 22% at optimum pH (pH 7.5–8.0). Adsorption isotherms fitted to the Langmuir model, which revealed the highest adsorption capacities for BEI and FeO-BEI (44.8 mg/g and 38.6 mg/g at 313 K). Preferential ion uptake followed in the order: Ba²⁺ > K⁺ > Ca²⁺ >> Mg²⁺ for all adsorbents; however, BEI and FeO-BEI showed the highest selectivity for Ba²⁺ among all materials tested. Barium removal from solution was governed by physical adsorption besides ion exchange, intercalation, surface complexation and precipitation, depending mainly on the absorbent type and operational conditions. BEI and FeO-BEI showed a high regenerability (>70–80% desorption efficiency after 5 cycles) and could be considered as efficient sorbent materials for wastewater clean-up. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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17 pages, 2338 KiB

Open AccessArticle

Development of an Adsorbing System Made of DMS-1 Mesh Modified by Amino Groups to Remove Pb(II) Ions from Water

by Viviana Palos-Barba, Cecilia Lugo-Nabor, Rodrigo R. Velázquez-Castillo, Dora Alicia Solís-Casados, Carmen L. Peza-Ledesma, Eric M. Rivera-Muñoz, Rufino Nava and Barbara Pawelec

Materials 2020, 13(8), 1914; https://doi.org/10.3390/ma13081914 - 18 Apr 2020

Viewed by 3334

Abstract

Water pollution by heavy metals represents several health risks. Conventional technologies employed to eliminate lead ions from residual or drinking water are expensive, therefore an efficient and low-cost technique is required and adsorption processes are a good alternative. In this work, the goal [...] Read more.

Water pollution by heavy metals represents several health risks. Conventional technologies employed to eliminate lead ions from residual or drinking water are expensive, therefore an efficient and low-cost technique is required and adsorption processes are a good alternative. In this work, the goal was to determine the adsorption capacity of a Disordered Mesoporous Silica 1 material (DMS-1) functionalized with amino groups, for Pb(II) ions removal. DMS-1 was prepared by sol-gel method and the incorporation of amino groups was performed by ex-situ method. As the source of amine groups, (3-Aminopropyl) triethoxysilane (APTES) was used and three different xNH₂/DMS-1 molar ratios (0.2, 0.3, 0.4) were evaluated. In order to evaluate the incorporation of the amino group into the mesopore channels, thermal and structural analysis were made through Thermogravimetric Analysis (TGA), nitrogen adsorption–desorption at 77 K by Specific Brunauer–Emmett–Teller (SBET) method, Fourier Transfer Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and X-Ray Photoelectron Spectroscopy (XPS). The higher Pb(II) ions removal was achieved with the 0.3 molar proportion of xNH₂/DMS-1 reaching 99.44% efficiency. This result suggests that the functionalized material can be used as an efficient adsorbent for Pb(II) ions from aqueous solution. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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18 pages, 3265 KiB

Open AccessArticle

Laponites^® for the Recovery of ¹³³Cs, ⁵⁹Co, and ⁸⁸Sr from Aqueous Solutions and Subsequent Storage: Impact of Grafted Silane Loads

by Thomas Thiebault, Jocelyne Brendlé, Grégoire Augé and Lionel Limousy

Materials 2020, 13(3), 572; https://doi.org/10.3390/ma13030572 - 25 Jan 2020

Cited by 3 | Viewed by 2448

Abstract

In this study, silylated Laponites^® (LAP) were synthetized with various loads of 3-aminopropyltriethoxysilane (APTES) to evaluate their adsorption properties of ¹³³Cs, ⁵⁹Co, and ⁸⁸Sr during single-solute and competitive experiments. The increase in the initial load of APTES increased the [...] Read more.

In this study, silylated Laponites^® (LAP) were synthetized with various loads of 3-aminopropyltriethoxysilane (APTES) to evaluate their adsorption properties of ¹³³Cs, ⁵⁹Co, and ⁸⁸Sr during single-solute and competitive experiments. The increase in the initial load of APTES increased the adsorbed amount of APTES in the resulted grafted clay. The characterization of LAP-APTES exhibited a covalent binding between APTES and LAP and emphasized the adsorption sites of APTES for each tested load. In comparison with raw LAP, LAP-APTES displayed significantly higher adsorption properties of Co²⁺, Cs⁺, and Sr²⁺. The competitive adsorption of these three contaminants provides a deeper understanding of the affinity between adsorbate and adsorbent. Therefore, Co²⁺ displayed a strong and specific adsorption onto LAP-APTES. Except for Cs⁺, the adsorption capacity was improved with increasing the load of APTES. Finally, the desorption behavior of the three contaminants was tested in saline solutions. Cs⁺ and Sr²⁺ were significantly released especially by inorganic cations displaying the same valence. Conversely, desorption of Co²⁺ was very low whatever the saline solution. LAP-APTES, therefore, presented suitable adsorption properties for the removal of radionuclides especially for Co²⁺, making this material suitable to improve the decontamination of radioactive wastewaters. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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Review

Jump to: Research

35 pages, 1962 KiB

Open AccessReview

Mineral Materials Coated with and Consisting of MnO_x—Characteristics and Application of Filter Media for Groundwater Treatment: A Review

by Magdalena M. Michel, Lidia Reczek, Dorota Papciak, Maria Włodarczyk-Makuła, Tadeusz Siwiec and Yuliia Trach

Materials 2020, 13(10), 2232; https://doi.org/10.3390/ma13102232 - 13 May 2020

Cited by 24 | Viewed by 4777

Abstract

For groundwater treatment, the technologies involving oxidation on MnO_x filter bed are beneficial, common, and effectively used. The presence of MnO_x is the mutual feature of filter media, both MnO_x-coated mineral materials like quartz sand and gravel, chalcedonite, diatomite, [...] Read more.

For groundwater treatment, the technologies involving oxidation on MnO_x filter bed are beneficial, common, and effectively used. The presence of MnO_x is the mutual feature of filter media, both MnO_x-coated mineral materials like quartz sand and gravel, chalcedonite, diatomite, glauconite, zeolite, or anthracite along with consisting of MnO_x manganese ores. This review is based on the analysis of research and review papers, commercial data sheets, and standards. The paper aimed to provide new suggestions and useful information for further investigation of MnO_x filter media for groundwater treatment. The presented compilations are based on the characteristics of coatings, methods, and conditions of its obtaining and type of filter media. The relationship between the properties of MnO_x amendments and the obtained purification effects as well as the commonly used commercial products, their features, and applications have been discussed. The paper concludes by mentioning about improving catalytic/adsorption properties of non-reactive siliceous media opposed to ion-exchange minerals and about possible significance of birnessite type manganese oxide for water treatment. Research needs related to the assessment of the use MnO_x filter media to heavy metals removal from groundwater in field operations and to standardize methodology of testing MnO_x filter media for water treatment were identified. Full article

(This article belongs to the Special Issue Novel Inorganic Adsorbents for Environmental Purification)

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