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1

Electrocoagulation Process for Chromium Removal in Leather Tanning Effluents

Hartati Etih, Hasyyati Lina, Permadi Didin Agustian, Djaenudin Djaenudin, Permana Dani, Putra Herlian Eriska

Journal of Ecological Engineering

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2024

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Vol. 25, nr 4

1--13

EN

The application of chromium sulfate in tanning operations yields chromium-laden wastewater, posing significant environmental risks. This research explored electrocoagulation as a remedial measure for tannery effluents. Varied parameters–pH (4, 7, 10), electric currents (0.5, 1.0, 1.5 A), and durations (1, 2, 3 h)–were optimized to diminish the chromium content. Evaluation based on initial and final chromium concentrations demonstrated 99.94% removal efficiency at pH 4, 1.5 A, over 3 hours. Achieving the 0.6 mg/L target concentration occurred at pH 4, 0.91 A, for 3 hours. This study highlighted the effectiveness of electrocoagulation in chromium mitigation within tannery wastewater, showcasing its potential as an environmentally sustainable remediation.

2

Wymywanie jonów magnezu, chromu, manganu i cynku z odpadów pohutniczych w zależności od pH opadów atmosferycznych

Kocoł Patrycja, Porębska Gabriela, Muller Dominik, Zalewska Aleksandra

Analit

|

2024

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Nr 14

19--28

PL

W niniejszym artykule zajęto się sprawdzeniem intensywności wymywania poszczególnych jonów metali z różnych warstw hałdy żużlu stalowniczego pochodzącej z huty stali w Ostrowcu Świętokrzyskim. Wymywania dokonano symulując opady atmosferyczne - wykorzystując wodę destylowaną, jak i sztuczne kwaśne deszcze (roztwór kwasu azotowego (V) o pH ≈ 2). Próbki pobrano z terenu składowiska odpadów poprzemysłowych, należących do firmy Madrohut w Krakowie, zarówno z wierzchniej warstwy hałdy jak i z głębokości 0.5 m w głąb hałdy, które zostały następnie poddane suszeniu na powietrzu. Do oznaczeń wykorzystano metodę Atomowej Spektrometrii Absorpcyjnej (ASA), a przedmiotem oznaczeń były cztery pierwiastki: Mg, Mn, Cr i Zn. Celem było sprawdzenie przenikania jonów metali z hałd żużlu stalowniczego do potencjalnych wód gruntowych i możliwego przez to zanieczyszczenia środowiska naturalnego.

EN

The presented article concerns an examination of the intensity of metal ion leaching in different layers of a steel slag heap originating from a steel mill located in Ostrowiec Świętokrzyski. Leaching was induced by simulating precipitation, using destilled water, and acidic rainwater (nitric acid solution of pH ≈ 2). The samples were collected, on site of factory landfill area of Madrohut company located in Cracow, from both surface layer the heap as well as from the layer around 0.5 m within the heap itself which were all subsequently air-dried for the period of two weeks. Quantification was conducted using the Atomic Absorption Spectrometry method (AAS) within a scope of four metal elements: Mg, Mn, Cr and Zn. The goal was to examine the metal ion leaching from steel slag heap into potential groundwater supply and the possibility of polluting the environment as the result.

3

Porównanie zawartości chromu i potasu w ekstraktach z wybranych rodzajów żużli

Kijowska Marlena, Koziara Natalia, Rębacz Michał, Trzop Natalia

Analit

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2024

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Nr 14

10--18

PL

W niniejszej pracy dokonano analizy, podczas której porównano zawartości chromu oraz potasu w ekstraktach z wybranych rodzajów żużli. Próbki poddane analizie zostały pobrane z hałd: żużlu stalowniczego z Ostrowca (warstwa wierzchnia i głęboka) oraz żużlu pochodzącego ze spalania odpadów komunalnych (różniącego się czasem składowania). Do wyznaczenia wybranych pierwiastków posłużono się techniką absorpcyjnej spektroskopii atomowej w przypadku chromu, natomiast do pomiaru ilości potasu zastosowano fotometrię płomieniową. Otrzymane wyniki wskazują, że żużel z procesu spalania opadów komunalnych charakteryzuje się wyższą zawartością chromu. W żużlu stalowniczym zauważalne jest obniżenie zawartości chromu w warstwie wierzchniej, co może wynikać z procesów wymywania, takich jak opady deszczu. W badanych próbkach stwierdzono większą ilość potasu niż chromu, zwłaszcza w żużlu uzyskanym ze spalania odpadów komunalnych, co jest rezultatem powszechnego występowania potasu w środowisku. Kryterium wyboru pierwiastków do analizy opierało się na ich potencjalnie negatywnym oddziaływaniu na środowisko, przede wszystkim chromu.

EN

In the present study, an analysis was carried out comparing the chromium and potassium contents of extracts from selected types of slag. Samples subjected to analysis were taken from heaps: steelmaking slag from Ostrowiec (top layer and the deep layer) and slag from municipal waste incineration (differing in the time of storage). Atomic absorption spectroscopy technique was used to determine the selected elements in the case of chromium, while flame photometry was used to measure the amount of potassium. The results obtained indicate that slag from the combustion process of municipal precipitation has a higher chromium content. In steelmaking slag, a reduction in chromium content in the surface layer is noticeable, which may be due to leaching processes such as rainfall. A higher amount of potassium than chromium was found in the samples, especially in slag obtained from municipal waste incineration, a result of the widespread occurrence of potassium in the environment. The criterion for selecting elements for analysis was based on their potential negative environmental impact, primarily chromium.

4

Badania nad wymywaniem chromu z żużli hałdowanych w zakładzie przetwórstwa odpadów

Izydor Kinga, Matlak Teresa, Myśliwiec Wiktoria, Wtorkowska Karolina

Analit

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2024

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Nr 14

48--58

PL

Artykuł koncentruje się na wpływie rozcieńczonych kwasów; solnego i azotowego na wymywanie chromu z żużli oraz kinetyce tego procesu. Zbadano również wpływ uziarnienia próbki na ilość wymywanego chromu. Próbki żużla stalowniczego oraz żużla ze spalarni pobrano z zakładu zajmującego się przetwórstwem odpadów. W pracy przedstawiono etapy przygotowania próbek oraz przebieg przeprowadzonej analizy. Badania ilościowe uzyskanych roztworów chromu wykonano metodą atomowej spektrometrii absorpcyjnej (ASA). Za pomocą analizy wyników stwierdzono, że z żużla stalowniczego wymywa się więcej chromu niż w przypadku żużla ze spalarni.

EN

The article focuses on the impact of dilute acids, namely hydrochloric and nitric acids, on the leaching of chromium from slag and the kinetics of this process. The influence of sample grain size on the amount of leached chromium was also examined. Samples of steel mill slag and incinerator slag were collected from a waste processing facility. The paper presents the stages of sample preparation and the process of the conducted analysis. Quantitative analysis of the obtained chromium solutions was performed using the method of atomic absorption spectrometry (AAS). The results analysis revealed that more chromium is leached from the steel mill slag compared to incinerator slag.

5

Czy specjacja pierwiastków w wodzie ma sens? Część l:Formy chemiczne chromu w wodzie

Zembrzuska Joanna, Kamgar Elham, Rychlewski Paweł

Technologia Wody

|

2023

|

Nr 1 (79)

37-40

PL

Rozwój nauki, świadomości społeczeństwa oraz wyniki prowadzonych badań toksykologicznych coraz wyraźniej wskazują, że w przypadku wielu pierwiastków nie jego całkowita zawartość lecz obecność jego form chemicznych wpływa na rozwój i stan zdrowia organizmów żywych. Z tego względu wydaje się być ważniejszym pozyskać informacje na temat form w jakich występuje od całkowitej jego zawartości. Formami chemicznymi pierwiastków, jakie wykazują aktywność biologiczną i toksyczność wobec organizmów żywych są formy jonowe. W artykule zostało poruszone zagadnienie specjacji i analizy specjacyjnej ze szczególnym zwróceniem uwagi na problem występowania chromu w wodzie do picia oraz w wodach powierzchniowych. Obecnie uregulowania prawne wskazują na monitorowanie całkowitej zawartości tego pierwiastka w wodzie. To podejście nie daje nam poczucia bezpieczeństwa, gdyż chrom ma zróżnicowane właściwości zależne od stopnia jego utlenienia. Chrom(lll) jest zaliczany do mikroelementów niezbędnych do prawidłowego funkcjonowania i rozwoju organizmu, zaś chrom (VI) ma negatywny wpływ na zdrowie człowieka. Przypisuje się mu działanie kancerogenne i mutagenne.

EN

The development of science, public awareness and the results of toxicological research show morę and more apparent that in the case of many elements, not their total content, but the presence of their chemical forms affects the development and health of living organisms. For this reason, it seems more important to obtain information on the forms in which it occurs than its total content. The chemical forms of elements that exhibit biological activity and toxicity to living organisms are ionic forms. The article deals with the issue of speciation and speciation analysis with patticular attention to the problem of the occurrence of chromium in drinking water and surface waters. Currently, legal regulations indicate the monitoring of the total content of this element in water. This approach does not give us a sense of security, because chromium has different properties depending on the degree of its oxidation. Chromium (III) is included among the microelements necessary for the proper functioning and development of the body, while chromium(VI) has a negative impact on human health. It is believed to be carcinogenic and mutagenic.

6

The effect on wear resistance of laser alloying with chromium and titanium of grey iron parts

Paczkowska Marta

Journal of Research and Applications in Agricultural Engineering

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2023

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Vol. 68, nr 2

26--35

EN

The aim of the presented study is to evaluate the influence of laser alloying with chromium and titanium on the surface layer microstructure and abrasive wear resistance of grey iron parts. A coulter flap was chosen as the object of this investigation. To produce the alloyed layer on the area of the flap that is the most exposed to wear, a diode laser was used as the heat source. The investigation demonstrated that laser alloying with chromium and titanium can increase the wear resistance of components working in abrasive conditions. A smaller mass loss after the wear tests in abrasive conditions of soil could be expected. The laser alloyed layer (with a depth of approx. 400 μm) was characterized by a martensite microstructure (mainly), homogenous morphology and fine grains. A fivefold increase in hardness (approximately 1050HV) in comparison to the hardness of the base material and twofold in comparison to the original ledeburitic surface layer of the coulter flap was noted. Some changes after laser alloying in the surface stereometry were observed (a decrease in the roughness parameters is possible). The roughness parameter values after the wear test decreased in the case of the original and alloyed coulter flaps..

7

Chromium Ions Removal by Capacitive Deionization Process: Optimization of the Operating Parameters with Response Surface Methodology

Issa Zainab M., Salman Rasha H.

Journal of Ecological Engineering

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2023

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Vol. 24, nr 1

51--65

EN

An innovative desalination method called electrosorption or capacitive deionization (CDI) has significant benefits for wastewater treatment. This process is performed by using a carbon fiber electrode as a working electrode to remove hexavalent chromium ions from an aqueous solution. The pH, NaCl concentration, and cell voltage were optimized using the Box-Behnken experimental design (BDD) in response surface methodology (RSM) to study the effects and interactions of selected variables. To attain the relationship between the process variables and chromium removal, the experimental data were subjected to an analysis of variance and fitted with a quadratic model. The optimum conditions to remove Cr(VI) ions were: pH of 2, a cell voltage of 4.3V, and NaCl concentration of 1.4 g/L. This study demonstrated that the carbon fiber electrode was very efficient in Cr(VI) ions removal and the BBD methodology was a practical and effective strategy for predicting the results of various experimental conditions during a CDI process for the removal of chromium ions.

8

The influence of selected transition elements on cell metabolism

Terpiłowska Sylwia, Rafińska Katarzyna, Gołębiowski Adrian, Kowalkowski Tomasz, Buszewski Bogusław

Ecological Chemistry and Engineering. S

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2023

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Vol. 30, nr 4

471--488

EN

The elements are present in the environment. Moreover, they are used in pharmacy and the production of new materials used in medical applications. They are often as environmental pollutants. They can accumulate in organisms and induce toxic effects on the cellular level. HepG2, L929 and Caco-2 cell lines were exposed to known concentrations of chromium chloride, iron chloride, nickel chloride, molybdenum trioxide and cobalt chloride (200 or 1000 μ M used alone and in combinations). Concentrations of chromium, iron, nickel, molybdenum and cobalt in the cell lysate and the culture medium were determined by ICP-MS. Moreover, sodium, potassium, calcium and magnesium concentrations were also measured. What is more, cells were observed under light and scanning electron microscope. The dose-dependent increase in the concentration of chromium, iron, nickel, molybdenum and cobalt in all cell lines after incubation with elements was observed. Potassium concentration decreases while sodium calcium and magnesium increase after incubation of cells with of mentioned elements. The incubation of cells with microelements induces cell morphology changes. The presented study shows the crucial role of tested microelements in the induction of cell death as a result of an imbalance of sodium, potassium, calcium and magnesium concentration inside the cell.

9

Nowa koncepcja badania specjacji – stabilizacja form w miejscu pobrania próbki

Drwal Alicja, Kovshun Lidia, Kowalska Joanna, Krasnodębska-Ostręga Beata

Analityka : nauka i praktyka

|

2023

|

nr 3

4-9

PL

Już podczas pobierania czy transportu próbek do laboratorium może dojść do zmian specjacji obecnych w próbce form arsenu czy chromu. Dość trudno temu zapobiec, a konserwacja sama w sobie może być czynnikiem zaburzającym pierwotną specjację – specjację opisującą badany obszar, region czy ekosystem. Dlatego obiecującym rozwiązaniem jest nowe podejście do próbki – nie modyfikowanie chemiczne w celu utrwalania specjacji ale rozdzielenie form mogących ulegać zmianie lub przejściu jedna w drugą już na miejscu pobrania próbek.

10

Characteristics and Adsorption Test of Activated Carbon from Indonesian Bituminous Coal

Kusdarini Esthi, Budianto Agus

Journal of Ecological Engineering

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2022

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Vol. 23, nr 10

129--138

EN

The fast-growing batik industry in Indonesia raises the problem of the waste containing chromium. One method to remove chromium is by the adsorption process using activated carbon. Activated carbon can be made from coal. This commodity is a mining mineral the availability of which is still abundant in Indonesia. This study aimed to obtain: 1) the best concentration of activator and activation temperature in the manufacture of activated carbon; 2) characteristics of activated carbon (moisture content, volatile matter content, ash content, fixed carbon content, iodine number, specific surface area, pore-volume, pore surface area, pore radius, and SEM photos); 3) % activated carbon removal for chromium and maximum adsorption capacity for chromium; 4) Freundlich and Langmuir isotherm adsorption equation of activated carbon to chromium. The manufacture of activated carbon was carried out by a carbonization process followed by a chemical and physical activation processes. The chemical activator was ammonium phosphate with doses of 74.5 g/L, 149 g/L, 223.5 g/L, and 298 g/L. Meanwhile, physical activation was carried out at 848 K, 948 K, 1048 K, and 1148 K. The next step was to test the adsorption capacity of activated carbon on artificial batik waste containing chromium. The results showed that: 1) activator concentration did not significantly affect the characteristics of activated carbon. Meanwhile, the optimal activation temperature is at a temperature of 1048 K and 1148 K, which can produce the activated carbon that meets the requirements of activated carbon of the Indonesian National Standard 06-3730-1995 with the following contents: air content 0.16–0.81%; volatile matter 14.62–19.31%; ash 6.48–9.97%; fixed carbon 70.60–75.79%; iodine number 1243.13–1258.65%; specific surface area 31.930 m2/g; activated carbon pore volume 0.011 cc/g; pore surface area 8.905 m2/g; activated carbon pore radius 30.614; 3) the proportion of activated carbon removal for chromium is 37–53% and the maximum adsorption capacity for chromium is 52 mg/g; 4) the Freundlich equation test resulted in a constant R2 of 0.5126, n 2.4870, KF 8.8818 mg/g, while the Langmuir equation test resulted in a constant R2 of 0.8897, b -0.0075 L/mg, qm -90.0901 mg/g.

11

Active Capping Treatment of Copper and Chromium Contaminated Sediment with Bentonite Kaolin and Sand to Inhibit their Release to the Overlying Water

Aliyu Mohammed Kabir, Abd Karim Ahmad Tarmizi Bn, Chan Chee Ming, Abdulkadir Aeslina, Bin Daud Zawawi, Oyekanmi Adeleke Abdulrahman

Journal of Ecological Engineering

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2022

|

Vol. 23, nr 12

264--272

EN

The public concern over sediment contamination brought on by mining operations, excessive use of chemical fertilisers or pesticides, industrial, agricultural, and municipal effluent, is increasing. Dredging is a more expensive treatment option than in situ capping of polluted sediment for immobilising pollutants in sediments on site. In order to stop the release of Cr and Cu from chemically contaminated sediments, this study aimed to evaluate the efficiency of utilising active capping materials such as bentonite (B), kaolin (K), and a 1:1 combination of bentonite and kaolin (BK) as capping materials. In a 90-day laboratory experiment carried out in glass tanks with a 1 cm thickness cover of capped material plus sand spread over the polluted sediment, the efficacy of B, K, and BK in inhibiting trace metal leachability was examined. The findings demonstrated that B and BK decreased the ability of sediments to leach Cr and Cu. The results suggest that BK and B should be considered as a suitable active material for capping treatment of polluted sediment sites because of their high Cu and Cr trapping. According to an analysis of adsorption kinetics, chemisorption was the adsorption process. The outcomes of this study demonstrated the potential for using kaolin, a bentonite-kaolin clay mixture covered with sand, and bentonite as capping materials for the in-situ treatment of Cr and Cu polluted coastal sediments.

12

High Structural Stability and Adsorption Capacity of Zn/Al-Biochar and Cu/Al-Biochar Toward Adsorption of Cr(VI)

Palapa Neza Rahayu, Taher Tarmizi, Siregar Patimah Mega Syah Bahar Nur, Normah, Juleanti Novie, Wijaya Alfan, Badri Arini Fousty, Lesbani Aldes

Journal of Ecological Engineering

|

2021

|

Vol. 22, nr 4

213--223

EN

Layered double hydroxide (LDH) Zn/Al and Cu/Al was synthesized by using the coprecipitation method under base condition at pH 10 following with formation of composites based on biochar (BC) to form Zn/Al-BC and Cu/ Al-BC. The materials were characterized by XRD, FTIR, BET, and thermal analyses. Furthermore, materials was applied as adsorbent of Cr(VI) on aqueous solution. The performance of composites as adsorbent was evaluated by reusability of adsorbent toward Cr(VI) adsorption process. The results showed that Cu/Al-BC and Zn/Al-BC can reuse the re-adsorption process with the adsorption ability of more than 60%. The adsorption capacity of Cu/ Al-BC and Zn/Al-BC was higher than that of starting materials and up to 384.615 mg/g for Cu/Al-BC and 666.667 mg/g for Zn/Al-BC. Both composites showed the potential adsorbents to remove Cr(VI) from aqueous solution.

13

Chromium Elimination from Contaminated Soil by Electro-Kinetic Remediation, Using Garlic Peels Powder

Hawal Laith Hamdan, Al-Sulttani Ali Omran, Kariem Nagam Obaid

Journal of Ecological Engineering

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2021

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Vol. 22, nr 7

252--259

EN

In this paper, an electro-kinetic technique was applied to remove chromium from contaminated soil. This technique is appropriate for the soils with low permeability. Various experiments were carried out under different operating conditions, including various purging solutions. Garlic peels powder (GPP) was used in this study as a cheap adsorbent substance to avert the flow of reverse osmosis, which may affect the removal percentage. The results proved that the removal percentage increased as the pH of the purging solutions decreased. The first three experiments were performed with purging solution at pH of 4, 6, and 8 respectively. The highest removal percentage was 66.3% at pH of 4 compared to the other two experiments at pH of 6 and 8, where the removal percentages were 53.3% and 49.7%, respectively. This paper showed that the percentage of chromium removal decreased along with the voltage. The removal percentage at 1.5 V/cm was 66.3%, while at 1 V/cm was 61%. Garlic peels powder (GPP) is considered as an effective adsorbent material to avert the reverse osmosis flow. Therefore, the use of this material in this study will give a new impression on the application of these products as an absorbent medium.

14

Badanie wpływu czasu składowania hałd szlamu z mokrego oczyszczania spalin z pieców hutniczych, na zawartość wybranych pierwiastków metali ciężkich

Czekaj Karolina, Klaper Natalia, Kozieł Tomasz

Analit

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2021

|

Nr 10

3--12

PL

W niniejszej pracy dokonano analizy wpływu czasu składowania hałd na zawartość wybranych pierwiastków metali ciężkich. Badanym materiałem były dwie hałdy szlamów i osadów pofiltracyjnych z oczyszczania gazów odlotowych, które różniły się czasem składowania. Analizowano je pod kątem wilgotności oraz zawartości cynku, manganu i chromu wykorzystując metodę absorpcyjnej spektroskopii atomowej. Hałda "Dąbrowa Stara", która pochodzi z przełomu roku 2020/2021 wykazała wilgotność na poziomie 39%. Natomiast hałda "Dąbrowa Nowa" została dostarczona we wrześniu 2021 r. i charakteryzowała się wilgotnością 47%. Otrzymane zawartości wody w próbkach zgadzają się z przedziałem otrzymanym przez firmę dla tego rodzaju surowca (30-50%). Badanie zawartości metali ciężkich wykazało największe stężenie cynku ze wszystkich oznaczanych pierwiastków, wyniosło ono dla próbki „Dąbrowa Stara” 17119 [μg/g], a dla próbki „Dąbrowa Nowa” 20385 [μg/g]. Najmniejszą ilość w badanych materiałach stanowił chrom, którego zawartość była nieznaczna. Dla próbki „Dąbrowa Stara” wartość oznaczonego stężenia wyniosła 127 [μg/g], a dla „Dąbrowa Nowa” 150 [μg/g]. Wykazano, że hałda "Dąbrowa Nowa" jest bardziej bogata w cynk, chrom i mangan niż hałda "Dąbrowa Stara". Różnice w zawartościach wykrywanych składników mogły być efektem wymywania ich np. poprzez opady deszczu co było spowodowane różnym czasem składowania obu hałd.

EN

In this publication, the effect of heap storage time on the content of the selected heavy metals was analysed. Two heaps of sludges and filter sludges from waste gas treatment, which differed in storage time, constituted the studied material. They were analyzed for moisture content and zinc, manganese and chromium concentrations using atomic absorption spectroscopy. „Dąbrowa Stara” heap, which dates back to the turn of 2020/2021, showed moisture content of 39%. The „Dąbrowa Nowa” heap, on the other hand, was delivered in September 2021 and had a moisture content of 47%. The obtained water contents in the samples agreed with the range obtained by the company for this type of raw material (30- 50%). The analysis of heavy metal contents showed the highest concentration of zinc of all determined elements, which was 17119 [μg/g] for the sample "Dąbrowa Stara" and 20385 [μg/g] for the sample "Dąbrowa Nowa". Chromium was the least abundant in the studied materials and its content was insignificant. For the sample "Dąbrowa Stara" the value of determined concentration was 127 [μg/g], and for "Dąbrowa Nowa" 150 [μg/g]. It was shown that the „Dąbrowa Nowa” is richer in zinc, chromium and manganese than the „Dąbrowa Stara”. The differences in the contents of the detected components could be the effect of their leaching e.g. by rainfall, which was caused by the different time of storage of the two heaps.

15

Związki kompleksowe chromu(III), wanadu(IV) i kobaltu(II) jako nowe prekatalizatory polimeryzacji olefin

Drzeżdżon Joanna

Wiadomości Chemiczne

|

2020

|

[Z] 74, 5-6

423--437

EN

The olefin polymerization catalysts constitute a large group of various compounds. Metallocene complexes are the largest part of this group. However, due to the instability at industrial plastics temperatures and the decomposition of complexes after MAO (or MMAO) activation, they have been partly replaced by non-metallocene compounds. This article concerns the studies on new non- metallocene precatalysts for the olefin polymerization and oligomerization. The report focuses on the structure and the catalytic activities of the complexes of chromium(III), vanadium(IV) and cobalt(II) with the following ligands: dipicolinate, 2-pyridinecarboxylate, oxalate, oxydiacetate, iminodiacetate, 2,2’- bipyridine, 4,4’-dimethoxy-2,2’-bipyridine, 1,10-phenantroline. These complex compounds are highly active precatalysts for olefin polymerization and oligomerization. The complexes: [Cr(dipic)2][Cr(bipy)(dipic)H20] 2H20 and [Cr(dipic) 2]Hdmbipy 2.5H20 deserve special attention because they are new type of the precatalysts i.e. organic salt type complexes composed both of organic cations and anions. These compounds are not only interesting because of their structure but also because of their high catalytic activity.

16

Selective solvent extraction of some heavy metal ions from aqueous solutions by octafunctionalized resorcin[4]arenes

Kończyk Joanna, Dlugosz Jan

Physicochemical Problems of Mineral Processing

|

2020

|

Vol. 56, iss. 2

271--285

EN

This paper presents the results of the study on the extraction capacity of 1,8,15,22-tetra(1- heptyl)resorcin[4]arene and its octasubstituted derivatives containing thiophosphoryl, ester and amide groups in the presence of Pb(II), Zn(II), Cd(II) and Cr(III) in solvent extraction process. Effects of the structure and concentration of the resorcinarene extractant and the composition of the aqueous phase as well as its acidity on the efficiency and selectivity of removal of the examined metal ions from model aqueous solutions were determined. The 1:1 stoichiometry for complexes formed between Pb(II) and Cr(III) and the octasubstituted resorcin[4]arenes was determined by classical slope analysis and loading test.

17

Effective Removal of Iron (II) from Aqueous Solution by Adsorption using Zn/Cr Layered Double Hydroxides Intercalated with Keggin Ion

Oktriyanti Melantina, Palapa Neza Rahayu, Mohadi Risfidian, Lesbani Aldes

Journal of Ecological Engineering

|

2020

|

Vol. 21, nr 5

63--71

EN

Zn/Cr and Zn/Cr layered double hydroxides (LDHs) intercalated with Keggin ion [α-SiW12O40]4-were successfully synthesized at room temperature and pH value of 10. The synthesized materials were characterized by means of the XRD, BET, and FT-IR analyses and used as an adsorbent iron(II). The adsorption process was investigated by studying pH, the kinetics, and thermodynamic properties of the adsorption process. The results showed the interlayer Zn/Cr LDHs was 7.53 Å and increase to 10.26 Å on Zn/Cr LDHs intercalated with Keggin ion [α-SiW12O40]4-. The BET analysis showed that the pore volume of both materials increased from 0.063 cm3 g-1 to 0.163 cm3 g-1. The pH point zero charge measurement for the Zn/Cr LDHs material was 10 while LDHs Zn/Cr intercalated with Keggin ion [α-SiW12O40]4- was 8. Zn/Cr LDHs intercalated with Keggin ion [α-SiW12O40]4- has higher adsorption capacity than Zn/Cr LDHs without intercalation. Desorption of iron (III) was successfully conducted using HCl as reagent showing the involvement of ion exchange in the adsorption.

18

Combined Adsorption of the Copper and Chromium Cations by Clinoptilolite of the Sokyrnytsya Deposit

Sabadash Vira, Gumnitsky Jaroslaw, Lyuta Oksana

Journal of Ecological Engineering

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2020

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Vol. 21, nr 5

42--46

EN

In the paper, the assessment of the impact of heavy metals on water objects, namely copper and chromium was performed, and the methods for their neutralization were defined. A scientifically grounded method for the selection of natural zeolite for the purification of wastewater from heavy metals has been developed, provided that they are jointly present. The physicochemical characteristics of two metals related to heavy metals are presented: copper and chromium. The methods for determining the sorption capacity of natural zeolite for copper and chromium compounds, as well as the methods of analytical control of the wastewater components were presented. The results of the experimental studies on the combined adsorption of copper and chromium cations by natural zeolite under static conditions were presented. The changes in the chemical composition of the zeolite surface as a result of heavy metal sorption have been investigated. The influence of the nature of the ions and the pH of the adsorption medium on the selectivity of the heavy metal ions extraction by zeolite was analyzed. A diagram of the composition of the solution, depending on the pH values, was constructed. The pH of the beginning of deposition of the corresponding heavy metal hydroxides on the zeolite surface was calculated. While analyzing the results of experimental studies on the combined adsorption of copper and chromium ions, it was found that the copper ions are significantly better adsorbed by the sorbent than the chromium ions. Despite the same concentration of the chromium and copper ions in solution, Cu2+ is extracted selectively. As can be seen from the results of experimental studies, the concentration of copper on the surface of the sorbent increases from 0.628% mass at a concentration of 0.01 g/dm3 to 47.380% mass at a concentration of 1 g/dm3. The studies on the static activity of clinoptilolite for the copper and chromium ions indicate a simultaneous mechanism of the process, which involves ion exchange and physical adsorption. The concentration of the chromium ions on the surface of the sorbent after adsorption depends on the increase of the concentration of Cr3+ in the original solution to a lesser extent. The results of the studies on the combined adsorption of the Cu2+ and Cr3+ ions indicate the possibility of their chromatographic separation, which makes their further use possible.

19

Chromium Accumulation by Avicennia alba Growing at Ecotourism Mangrove Forest in Surabaya, Indonesia

Titah Harmin Sulistiyaning, Pratikno dan Herman

Journal of Ecological Engineering

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2020

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Vol. 21, nr 2

222--227

EN

The Ecotourism Mangrove Forest at Wonorejo in East Coast Surabaya area is one of large mangrove forests inside in the metropolitan city in Indonesia. There are many ecological values of the mangrove forest in most tropical countries such as sea fisheries, place of sea and coastal animals, sea and brackish water quality protecting the endangered mangrove coastlines and development of human life. The role of mangrove in increasing the sea and brackish water quality can be shown through many processes such as cycling of nutrients, particulate matter and some pollutants in water and sediment around the mangrove plants. One of the inorganic pollutants that can be removed by mangrove are heavy metals, such as chromium (Cr). The Wonorejo River is one of the rivers that receive the disposal of wastewater in Surabaya East Coast area. Large quantitites of wastewater from industries and households were released to this river. The concentration of Cr at the Wonorejo Estuary reached 0.0325 mg/L and 2.7761 mg/L in sediments. The purpose of this research was to determine the potency of Cr accumulation by Avicennia alba that was grown for ten years at Wonorejo Ecotourism Mangrove Forest. The sampling activities were conducted using a transect quadrat sampling method with a 10x10 m dimension. The sediment and mangrove root samples were extracted before being analysed using an atomic absorption spectrophotometer (AAS). The results showed that the Cr accumulation by roots of A. alba reached 25.4 ± 1.6 to 55.3 ± 1.1. The BCF value in A. alba were 0.32 ± 0.01 to 0.83 ± 0.5 with the concentration Cr in sediment were 60 ± 1.4 to 79.3 ± 1.1. A. alba showed potential as a moderate accumulator for Cr. In conclusion, A. alba can be considered for use in phyto-monitoring and phytoremediation of Cr in coastal areas.

20

Oznaczanie form specjacyjnych chromu w próbkach wód głębinowych metodą katalityczno-adsorpcyjnej woltamperometrii stripingowej

Ciężkowska Magda, Rudy Aneta

Analit

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2020

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Nr 9

19--26

PL

W pracy opisano metodę oraz wyniki oznaczenia dwóch form specjacyjnych chromu w wodach, pochodzących z sześciu artezyjskich studni głębinowych, znajdujących się na terenie miasta Krakowa. Powodem celowości oznaczenia chromu w wodach głębinowych, przeznaczonych do spożycia są silnie zróżnicowane właściwości jonów chromu (III) i chromu (VI) szczególnie jeżeli chodzi o ich wpływ na organizm ludzki. Chrom(III) jest zaliczany do mikroelementów niezbędnych do prawidłowego funkcjonowania i rozwoju organizmu. Chrom (Vl) ma negatywny wpływ, gdyż przypisuje się mu działanie mutagenne, a nawet kancerogenne. Jako metodę specjacyjnego oznaczania obu form jonów chromu wybrano katalityczno-adsorpcyjną woltamperometrię stripingową (CAdSV) połączoną z rejestracją katodowych woltamogramów techniką impulsej woltamperometrii różnicowej (DPV). Spośród wielu znanych metod instrumentalnych metoda DP CAdSV cechuje się największą precyzją, dokładnością i czułością pomiaru. Co szczególnie ważne próbki wody przeznaczone do analizy woltamperometryczej nie wymagają wstępnego przygotowania, w efekcie metoda spełnia rygorystyczne wymagania zielonej chemii analitycznej (ang. Green Analytical Chemistry).

EN

The publication describes the method and results of determination of chromium speciation forms in deep-water samples. The samples came from six deep wells located in the city of Cracow. The reason for the determination of chromium in water is the different properties of Cr(III) and Cr(Vl) ions, especially their effect on the human body. Chromium (III) is essential for the proper functioning and development of the organism. Chromium (VI) has a negative effect because it acts mutagenically and even carcinogenically. The catalytic adsorptive stripping voltammetry (CAdSV) has been chosen as the method of chromium quantitative determination. Differential pulse voltammetry (DPV) technique was used to record cathodic voltammograms. Among the many instrumental methods, the DP CAdSV is characterized by the highest precision, accuracy, and sensitivity of measurements. It is important that the water samples intended for this analysis do not require any preliminary preparation, so the method meets the requirements of Green Analytical Chemistry.