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Skuteczność syntetycznych zeolitów w usuwaniu metali ciężkich i substancji organicznych z roztworów wodnych

Medykowska Magdalena

Wiadomości Chemiczne

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2023

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[Z] 77, 1-2

97--117

EN

With constantly increasing ecological needs, it is necessary to look for suitable solutions aimed at purifying the water and soil environment. Synthetic zeolites, i.e. porous, ion-exchangeable, acid- and heat-resistant, sodium and calcium aluminosilicates, may be the answer to this demand. This paper presents the adsorption capabilities of two synthetic zeolites (Na-X, Na-P1) obtained via hydrothermal reaction of aqueous sodium hydroxide and high-carbon fly ash. For this purpose, the experiment was conducted with adsorbates from two groups: heavy metals (Pb(II), Zn(II)) and organic substances (polymer - poly(acrylic acid) (PAA), nonsteroidal anti-inflammatory drug – diclofenac (DCF)). Adsorption was carried out in single and mixed adsorbate systems (metal-metal; metal-organic substance; organic substance-organic substance). The adsorption capacity of the studied zeolites was determined relative to Pb(II), Zn(II) and DCF. Desorption processes were also carried out to illustrate the regeneration abilities of the examined porous materials. In addition, the structure of the electrical double layer was characterized using potentiometric titrations and electrophoretic mobility measurements. The highest adsorbed amounts of heavy metals in single systems are observed for Na-X, i.e. 322.1 mg/g Pb(II) and 332.5 mg/g of Zn(II). In the case of Na-P1 zeolite, these amounts were 332.9 mg/g and 103.6 mg/g for Pb(II) and Zn(II), respectively. In mixed adsorbate systems there is a decrease in heavy metal adsorption, after the addition of both another metal or organic substance. In the first case, the decrease is small - the adsorption of Pb(II) on Na-X drops to 309.36 mg/g. In contrast, in mixed systems in the presence of anionic organic substances, the decrease in the amount of adsorbed ions is much greater. In the presence of DCF, Pb(II) adsorption on Na-X decrease to 98.7 mg/g, whereas on Na-P1 to 99.7 mg/g. The main mechanisms of the adsorption process in such systems are: competition for the adsorbent's active sites and the formation of complexes between adsorbates of opposite ionic character. However, the addition of a heavy metal causes increase of the drug adsorption. In the case of Pb(II) ions, the amount of DCF adsorbed on Na-X increases from 6.68 mg/g to 12.86 mg/g, and a slight decrease is observed on Na-P1. On the other hand, in the presence of PAA, DCF adsorption on Na-X decreases to 5.86 mg/g. Moreover, the synthesized adsorbents can be successfully regenerated with hydrochloric acid (in the single and mixed systems containing heavy metals). The addition of Pb(II)/Zn(II) and PAA causes a decrease in the zeta potential of the examined zeolites, whereas the addition of DCF increases this parameter. In turn, the surface charge density decreases in the presence of each adsorbate. It was proved that both synthetic zeolites can be successfully used in soil and water purification processes in continuously improved procedures.

2

Removing Heavy Metals through Different Types of Soils and Marble Powder found in Oman

Wazwaz Aref, Al-Salaymeh Ahmed, Khan Mohd Shariq

Journal of Ecological Engineering

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2019

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Vol. 20, nr 4

136--142

EN

In this research, adsorption followed by filtration was used for removing heavy metals (Cu, Zn, Mn, and Cr) from the polluted water. Three types of soils (silty, sandy and clay) and three types of marble powder (pure, impure, marble-granite mix) were used as an adsorbent. The soil and marble samples were collected from different regions of Oman. The maximum adsorption obtained was 96.01% for Zn using pure marble powder and the minimum adsorption obtained was 6.70% for Mn using impure marble powder. Through different soils, the maximum adsorption of 88.61% was achieved for Zn using clay and the lowest one is for Cr 16.51% using silty soil. The results suggest that among the marble powders, the pure ones show the maximum (96.01% for Zn) and marble-granite show the minimum (Mn 6.70%) adsorption performance. Among the adsorbents, Zn is the best adsorbate (96.01%) while the worst among the group is Mn, which merely adsorbed 6.70% with the selected adsorbents.

3

Effect of the strong magnetic field on copper adsorption processes on activated carbon

Rajczykowski K., Loska K.

Challenges of Modern Technology

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2017

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Vol. 8, no. 2

7--10

EN

In the presented studies an influence of the strong static magnetic field on the process of copper adsorption on activated carbon was analysed. The magnetic field was generated by the annular neodymium magnets, placed at the bottom of the glass reactors, with the magnetic induction value at the surface equal 0.517 T. Additionally, during the study an effect of temperature on the adsorption process efficiency and its susceptibility to the external magnetic field was also investigated. As a result of the study, it was found that using a magnetic modification can increase the efficiency of the adsorption process up to 80%. However, such a strong influence of the external magnetic field was observed only in the case of relatively low initial and equilibrium concentration of the adsorbate. With the increase of the equilibrium concentration, stimulating nature of the magnetic field weakened significantly until finally at an equilibrium concentration about 80 mg/dm3, it was almost negligible. In addition, it was also found that the magnetic field modifications were much more efficient if the adsorption processes were conducted at the higher temperature.

4

Adsorption of copper ions from aqueous solutions on natural zeolite

Zendelska A., Golomeova M., Blazev K., Krstev B., Golomeov B., Krstev A.

Environment Protection Engineering

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2015

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Vol. 41, nr 4

17--36

EN

The adsorption of copper ions from synthetic aqueous solutions on natural zeolite (clinoptilolite) was examined. In order to determine the rate of adsorption and the copper uptake at equilibrium, a series of experiments were performed under batch conditions from single ion solutions. Equilibrium data were evaluated based on adsorption (Langmuir and Freundlich) isotherms. The adsorption kinetics is reasonably fast. In the first 20 min of the experiment, approximately 80% of Cu2+ ions is adsorbed from the solutions. Data obtained from the kinetic experiments have been described by the pseudo-second order kinetic model as well as by the Weber–Morris and Furusawa–Smith models.

5

Zastosowanie minerałów ilastych do usuwania metali ciężkich

Mlaś A., Petryniak J., Ryznar A., Sobolewska P., Warchoł J.

Zeszyty Naukowe Politechniki Rzeszowskiej. Budownictwo i Inżynieria Środowiska

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2011

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z. 58, nr 2

177-195

PL

Artykuł stanowi przegląd literatury na temat sorpcji jonów metali ciężkich z roztworów wodnych na minerałach ilastych. Przedstawiono charakterystykę najważniejszych przedstawicieli należących do tej grupy minerałów: kaolinitu, montmorillonitu, bentonitu oraz chlorytu. Omówiono właściwości fizyczne, elektrochemiczne i zastosowanie naturalnych oraz modyfikowanych minerałów ilastych. Porównano efektywność usuwania jonów metali ciężkich na wybranych sorbentach naturalnych i poddanych modyfikacji.

EN

The article presents a review of heavy metal ions removal adsorption on natural clay minerals. The characteristics of the mineral specifications such as montmorillonite, bentonite, kaolinite and chlorite has been presented. The physical, electrochemical properties as well as a practical application of natural and modified clay minerals has been discussed. The adsorption affinity of natural and chemical modified clay minerals towards heavy metals ions has been compared.

6

Usuwanie i podział fazowy metali ciężkich w ekosystemie oczyszczalni hydrofitowej zasilanej odciekami ze składowiska odpadów komunalnych

Wojciechowska E.

Gaz, Woda i Technika Sanitarna

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2009

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Nr 7-8

51-54

EN

Evaluation of the influence of alternate aeration in oxygen phases on the possibility of obtaining synergic bio-genes removal in the process of de-phosphatizing de-nitrification in batch reactor. The issue was analyzed on the basis of experiment results; two research series on sewage treatment effectiveness in SBR reactor were conducted. The reactor worked in an 8-hour cycle, but with different systems and durations of oxygen and anoxic/oxygen-free phases as well as different multiplication factor for sewage dosing with its constant volume reaching the reactor during the whole cycle.

7

Zastosowanie aktywowanego bentonitu do usuwania metali ciężkich ze ścieków i wód odpadowych

Legutko M., Piątkowska M., Stechman M.

Chemik

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2007

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Vol. 60, nr 10

491-495

PL

W większości ciągów technologicznych oczyszczalni ścieków metale ciężkie wytrąca się w postaci wodorotlenków, siarczków lub fosforanów. Dobrym środkiem wspomagającym doczyszczanie ścieków do wymaganego poziomu jest zastosowanie adsorpcji z użyciem sorbentów naturalnych, ewentualnie po niewielkiej ich modyfikacji. W ramach pracy przebadano możliwość zastosowania bentonitu, którego głównym składnikiem jest Ca-montmorylonit, do usuwania kationów ołowiu, kadmu, miedzi i cynku ze ścieków. Stosując modelowe roztwory badanych metali określono optymalne warunki sorpcji, tj. dawkę sorbenta, odczyn środowiska reakcji, czas kontaktu. Otrzymane wyniki badań zweryfikowano na próbkach ścieków rzeczywistych.

EN

In most technologies of sewage treatment plant, heavy metals are precipitated in form of hydroxides, sulphides or phosphates. It seems, one of the best resource supports purifying sewage to required contaminant concentration is use of adsorption process with natural sorbents, alternatively after their small modification. In frames of work possibility of using bentonite, which main component is Ca-montmorillonite, to remove lead, cadmium, copper and zinc cations in sewage were investigated. The effect of contact time, pH, initial ion concentration and adsorbent dose, on the optimum sorption conditions of metals ions in testing solutions have been studied in detail. Received results of investigations were verified on real sewage samples.