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Tytuł:
Sorption of Cd(II), Ni(II) and Zn(II) on natural, sodium-, and acid-modified clinoptilolite-rich tuff
Autorzy:
Abatal, M.
Olguin, M. T.
Abdellaoui, Y.
El Bouari, A.
Powiązania:
https://bibliotekanauki.pl/articles/208078.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
heavy metals
clinoptilolite
cadmium removal
metale ciężkie
klinoptylolit
usuwanie kadmu
Opis:
Sorption of Cd2+, Ni2+and Zn2+ions on natural (ZPCli), sodium modified (ZPCliNa) and acid modified (ZPCliH) zeolites have been investigated in function of the contact time, pH, and metal concentration by the batch technique. The characterization of ZPCIi, ZPCliNa, and ZPCliH materials was performed using X-ray powder diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy techniques. The surface area (BET) and the pHpzcwere also determined. The pH in the point of the zero charge of ZPCli, ZPCliNa, and ZPCliH zeolites was 8.25, 8.00, and 2.05, respectively. The kinetic sorption data for ZPCli, ZPCliNa and ZPCliH were well fitted to the pseudo-second order model (R2> 0.99). The linear model described the Cd, Ni and Zn sorption isotherms for ZPCliH, while for ZPCliNa and ZPCliH it was the Freundlich model. The unmodified and modified zeolitic materials showed the highest sorption capacity for Cd2+, lower for Zn2+ and Ni2+.
Źródło:
Environment Protection Engineering; 2018, 44, 1; 41-59
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Removal of chromium(VI) from wastewater through ion exchange. Kinetic and scale up studies
Autorzy:
Ahmad, Syed Waqas
Zafar, Muhammad Shahzad
Ahmad, Sajjad
Zia-Ul-Haq, M.
Ashraf, Muhammad
Rabbani, Javed
Ullah, Sami
Powiązania:
https://bibliotekanauki.pl/articles/208034.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
ion exchange
industrial wastewater
anion resin
heavy metals
cadmium
wymiana jonowa
ścieki przemysłowe
żywica anionowa
metale ciężkie
kadm
Opis:
Chromium(VI) ions were removed from industrial wastewater. In this regard, a rig was fabricated carrying alkaline anion resin. Various experiments were carried out by varying pH, temperature and volumetric flow rate of solution by employing a rig to study the kinetics of the ion exchange process. The rate constant (k) and maximum solid phase concentration of exchanged solute (q0) were calculated using the Thomson equation to scale up the purification process of industrial runoff of chromium(VI) from the tanning, photography and ceramic industry. Experimental optimization revealed that developed setup will remove chromium(VI) to a level of 5 mg/dm3 from 300 mg/dm3 in 40 000 dm3 of wastewater. To achieve the best results for the flow rate of 10 000 3 3/day, 12.03 kg of anionic resin were recommended by fixing the pH of the setup at 7.4 while maintaining the treatment temperature at 20 °C.
Źródło:
Environment Protection Engineering; 2019, 45, 1; 17-29
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dry Biosolids Reuse as Costless Biodegradable Adsorbent for Cadmium Removal from Water Systems
Autorzy:
Ammari, Tarek G.
Al-Hadidi, Majida
Al-Kharabsheh, Noor
Khater, Dima
Abu-Romman, Saeid
Powiązania:
https://bibliotekanauki.pl/articles/1838412.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
adsorption
Cd-contaminated environment
untreated biosolids
intraparticle difusion model
Langmuir isotherm model
Opis:
The recycling of untreated dry biosolids, as costless biodegradable adsorbent for the removal of cadmium from aqueous phase was characterized. The adsorption of cadmium was reported to depend on initial pH, adsorbent dose, agitation time, and initial Cd concentration. The results of the batch experiments revealed that the maximum adsorption capacity of the untreated dry biosolids was 39.22 mg g-1 under optimum operating conditions (i.e. pH: 5, adsorbent dose: 2 g l-1, contact time: 16h). Adsorption reaches equilibrium after 16h, which can be attributed to both external surface adsorption (R2 = 0.86) and intraparticle dif usion (R2 = 0.98). The Langmuir isotherm model best described cadmium adsorption (R2 = 0.99) and the pseudo-second-order kinetic model was obeyed, suggesting that the mechanism involved was chemisorption. Biodegradability would make the recovery of adsorbed Cd an environmentally friendly process. Comparing the obtained findings with the related published results, it can be concluded that treating biosolids might be an unnecessary and costly procedure for recycling biosolids as an adsorbent for cadmium.
Źródło:
Journal of Ecological Engineering; 2021, 22, 5; 1-12
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Removal of zinc, cadmium and nickel from mining waste leachate using walnut shells
Autorzy:
Ayala, Julia
Fernandez, Begona
Powiązania:
https://bibliotekanauki.pl/articles/208277.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
metal ions
adsorption
biosorption
adsorbent
kinetics
copper
jony metali
adsorpcja
biosorpcja
kinetyka
miedź
Opis:
The removal of heavy metals from aqueous solutions using walnut shells was investigated. The effects of pH, contact time, initial metal concentration, adsorbent concentration, and co-ions were studied in synthetic solutions. Metal uptake was found to be dependent on the initial pH of the solution; the removal rate increased upon increasing pH, showing the highest affinity at pH 5–7. The amount of metal removed improved with increasing initial concentration. Increasing adsorbent dosage enhanced removal efficiency, but reduced the amount absorbed per unit mass of walnut shells. The presence of co-ions suppressed the uptake of heavy metals, divalent ions having a more negative effect than monovalentions. The adsorption of Zn, Cd and Ni onto walnut shells was found to fit Langmuir and Freundlich isotherms. The results obtained in the tests with mining waste leachate showed the potential use of walnut shells for the removal of heavy metals.
Źródło:
Environment Protection Engineering; 2019, 45, 2; 141-158
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phosphate ore washing by Na2EDTA for cadmium removal: Optimization of the operating conditions
Autorzy:
Benredjem, Z.
Delimi, R.
Khelalfa, A.
Powiązania:
https://bibliotekanauki.pl/articles/779151.pdf
Data publikacji:
2012
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
phosphate ore washing
cadmium
environment
extraction
chemical processes
optimization
Opis:
This paper discusses the extraction of cadmium from phosphate ore by the washing method. Various parameters were investigated for the cadmium extraction from phosphate ore. The results from extraction tests showed that cadmium extraction depends on the nature and concentration of the extracting agent, the liquid/phosphate ore ratio, the temperature and the solution pH. The effi ciency of the nine extracting agents for removing cadmium from phosphate ore was found to be in the order: Na2EDTA > citric acid > tartric acid > ammonium citrate > calcium chloride > ammonium acetate > ammonium chloride > oxalic acid > ammonium hydroxide. In this study cadmium extraction kinetics was best described by the product layer diffusion control model.
Źródło:
Polish Journal of Chemical Technology; 2012, 14, 3; 15-20
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Removal of lead, cadmium and copper ions from aqueous solutions by using ion exchange resin C 160
Usuwanie jonów ołowiu, kadmu i miedzi z roztworów wodnych za pomocą żywicy jonowymiennej C 160
Autorzy:
Bożęcka, A.
Orlof-Naturalna, M.
Sanak-Rydlewska, S.
Powiązania:
https://bibliotekanauki.pl/articles/216825.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN
Tematy:
ion-exchange resin
ion exchange
lead
cadmium
copper ions
jonit
wymiana jonowa
jony ołowiu
jony kadmu
jony miedzi
Opis:
Industrial waste solutions may contain toxic Pb, Cu, Cd and other metal ions. These ions may also be components of leachates in landfills of ores. The toxicity of the ionic forms of these metals is high. For this reason the paper presents the results of studies on one of the methods to reduce their concentration in aqueous solutions. The article presents the results of studies on the removal of Pb2+, Cd2+ and Cu2+ ions from model aqueous solutions with synthetic ion exchange resin C 160 produced by Purolite. The investigated ion exchanger contains sulfonic acid groups (–SO3H) in its structure and is a strongly acidic cation-exchange resin. The range of the studied initial concentrations of the Pb2+, Cd2+ and Cu2+ ions in the solutions was from 6.25 mg/L to 109.39 mg/L. The results confirmed that the used ion exchange resin C160 efficiently removes the above-mentioned ions from the studied solutions. The highest degree of purification was achieved in lead solutions for the assumed range of concentrations and conditions of the ion exchange process. It reached 99.9%. In the case of other solutions, the ion exchange process occurs with lower efficiency, however it remains high and amounts to over 90% for all the ions. The results of research were interpreted on the basis of the Langmuir adsorption model. For each studied ion, sorption capacity of the ion exchange resin increases until the saturation and equilibrium state is reached. Based on the interpretation of the Langmuir equation coefficients, an indication can be made that the studied ion exchange resin has a major sorption capacity towards the copper ions. In their case, the highest value of constant qmax was obtained in the Langmuir isotherm. For Cu2+ ions it was 468.42 mg/g. For Pb2+ and Cd2+ ions, this parameter reached the values of 112.17 mg/g and 31.76 mg/g, respectively. Ion exchange resin C 160 shows the highest affinity for the Pb2+ ions. In this case, the achieved value of coefficient b is highest and equals 1.437 L/mg.
Roztwory odpadowe zawierające m.in. jony metali Pb, Cu, Cd i inne powstają w przemyśle elektrochemicznej obróbki metali, w przemyśle przeróbki rud metali nieżelaznych, a także mogą być składnikiem odcieków ze składowisk odpadów tych rud. Toksyczność jonowych form tych metali jest znaczna, stąd w pracy podano wyniki badań jednego ze sposobów obniżenia ich koncentracji w roztworach wodnych. W artykule podano wyniki badań dotyczących usuwania jonów Pb2+, Cd2+ i Cu2+ z modelowych roztworów wodnych za pomocą syntetycznej żywicy jonowymiennej C 160 firmy Purolite. Badany jonit zawiera w swojej strukturze grupy sulfonowe (–SO3H) i należy do silnie kwaśnych kationitów. Zakres badanych stężeń początkowych jonów Pb2+, Cd2+ i Cu2+ w roztworach wynosił od 6,25 mg/dm3 d o 109,38 m g/dm3. Otrzymane wyniki potwierdziły, że wykorzystana żywica jonowymienna C160 skutecznie usuwa wymienione jony z badanych roztworów. Dla przyjętego zakresu stężeń i warunków procesu wymiany jonowej, największy stopień oczyszczenia roztworów osiągnięto dla ołowiu. Wynosił on 99,9%. W przypadku pozostałych roztworów wymiana jonowa zachodzi z wydajnością niższą, ale wysoką i wynosi dla wszystkich jonów ponad 90%. Wyniki badań zinterpretowano opierając się na modelu adsorpcji Langmuira. Dla każdego badanego jonu pojemność sorpcyjna jonitu wzrasta, aż do osiągnięcia wysycenia i stanu równowagi. Z interpretacji współczynników równania Langmuira wynika, że badany jonit charakteryzuje się największymi zdolnościami sorpcyjnymi w stosunku do jonów miedzi. W ich przypadku otrzymano największą wartość stałej qmax izotermy Langmuira. Dla jonów Cu2+ wyniosła ona 468,42 mg/g. Dla jonów Pb2+ i Cd2+ parametr ten przyjął odpowiednio wartości 112,17 mg/g i 31,76 mg/g. Jonit C160 wykazuje największe powinowactwo w stosunku do jonów Pb2+. W tym przypadku otrzymana wartość współczynnika b jest największa i równa 1,437 dm3/mg.
Źródło:
Gospodarka Surowcami Mineralnymi; 2016, 32, 4; 129-139
0860-0953
Pojawia się w:
Gospodarka Surowcami Mineralnymi
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badania możliwości wykorzystania bakterii naturalnego cyklu siarki do usuwania kadmu ze ścieków
Importance of the bacteria of the natural sulfur cycle to cadmium removal from wastewater
Autorzy:
Grübel, K.
Machnicka, A.
Powiązania:
https://bibliotekanauki.pl/articles/236484.pdf
Data publikacji:
2006
Wydawca:
Polskie Zrzeszenie Inżynierów i Techników Sanitarnych
Tematy:
oczyszczalnia ścieków
bakterie redukujące siarczany
bakterie siarkowe
siarczany
siarczki
kadm
wastewater treatment
sulfur reducing bacteria (SRB)
sulfur bacteria
sulfates
sulfides
Opis:
Omówiono możliwości wykorzystania wybranych bakterii naturalnego obiegu siarki do usuwania kadmu i siarczków ze ścieków oraz redukcji siarczanów. Badania zrealizowano w dwóch etapach, wykorzystując ścieki syntetyczne. Pierwszy etap przebiegał w warunkach beztlenowych, natomiast drugi w warunkach tlenowych. Podczas desulfurykacji użyto bakterie z rodzaju Desulfovibrio, natomiast w procesie tlenowym bakterie Acidithiobacillus ferrooxidans. Wykazano, że pierwszy etap spowodował całkowite usunięcie kadmu ze ścieków oraz obniżenie zawartości siarczanów o 53÷86%, w zależności od warunków procesu. Procesy tlenowe umożliwiły prawie 100% usunięcie siarczków.
The aim of the study was to highlight two potential uses of selected bacteria of the natural sulfur cycle: the removal of cadmium and sulfides from wastewater and the reduction of sulfates. Investigations were carried out in two steps (under anaerobic and aerobic conditions, respectively), with synthetic wastewater as the feed. The desulfurication process involved bacteria of the genus Desulfovibrio sp., while in the aerobic step use was made of Acidithiobacillus ferrooxidans. The anaerobic step of the study brought about a complete removal of cadmium from the wastewater and an approximately 53% to 85% reduction in the concentration of sulfates, depending on the process conditions applied. The aerobic processes accounted for an almost 100% removal of sulfides.
Źródło:
Ochrona Środowiska; 2006, R. 28, nr 2, 2; 27-31
1230-6169
Pojawia się w:
Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cadmium Removal from Contaminated Soil by Electro-Kinetic Method
Autorzy:
Hawal, Laith Hamdan
Al-Sulttani, Ali Omran
Hamza, Jinan N.
Powiązania:
https://bibliotekanauki.pl/articles/2202315.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
electrokinetic method
cadmium
soil
removal rate
rice husk
Opis:
For this study, an electro kinetic method used to eliminate cadmium from the polluted soil. This method is useful at low permeability medium. Several experiments were conducted with variable operating circumstances, using different pH purging solutions. Rice husks were used in this work as an adsorbent medium available and free of charge to counteract the reverse osmosis process that occurs and affects the work efficiency. The final results after the end of the practical experiments of this process showed that the percentages of the removal process began to increase after the pH gradually decreases. The pH of the solution for the three experiments conducted was 3, 6 and 9, respectively. The best removal rate was 68% in this process at pH 3 ; when compared with the second and third tests at pH 6 and 9, the removal ratios were 58% and 51.5%, respectively. It was discovered that the cadmium removal rate began to decrease along with voltage. At 30 volts the removal rates were 68%, whereas 20 volts they were 66%. Rice husks have been shown to be an effective adsorbent for counteracting reverse osmosis. Therefore, it can be successfully used as an adsorbent medium.
Źródło:
Journal of Ecological Engineering; 2023, 24, 1; 79--86
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative assessment of Al2O3 modified biomasses from agricultural residues for nickel and cadmium removal
Autorzy:
Herrera-Barros, Adriana
Tejada-Tovar, Candelaria
Gonzalez-Delgado, Angel D.
Powiązania:
https://bibliotekanauki.pl/articles/1844335.pdf
Data publikacji:
2021
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
adsorption
agricultural residues
alumina nanoparticles
cellulose
heavy metal ions
Opis:
The biodiversity of aqueous environments has been affected due to the disposal of wastewater highly contaminated with heavy metal ions, causing much damage to ecosystems. These pollutants are very toxic and bioaccumulate in living organisms. This work attempts to evaluate the adsorption of nickel ad cadmium ions using three biomasses from agricultural residues (corn cob – CC, orange peel – OP, and oil palm bagasse – PB) modified with alumina nanoparticles. The biomasses were characterized via compositional analysis and a point of zero charges to quantify the presence of lignin, cellulose, hemicellulose, and the feasible pH, taking advantage of the biomass charge. After modification with Al2O3 nanoparticles. The resulting adsorbents were characterized via FT-IR analysis to identify the functional groups that most contributed to the adsorption performance. Furthermore, the influence of Al2O3 nanoparticles was analysed on the adsorption capacities of the evaluated biomasses using batch systems at a temperature of 25°C and pH 6. All biomasses displayed a high content of cellulose, estimating a weight percentage of about 19.9%, 14.3%, and 13.1% for PB, OP, and CC samples, respectively. The FT-IR spectrum confirmed hydroxyl and carboxyl functional groups, which contribute to enhancing the adsorption capacities of the modified biomasses. Functional adsorption capacity was observed for all biomasses after modification with Al2O3 nanoparticles, achieving at pH 6.0 a cadmium removal from 92% (CC-Al2O3 and PB-Al2O3) up to 95.8±0.3% (OP-Al2O3). In nickel ions, it was estimated a broader adsorption capacity at pH 6.0 of about 86±0.4% after using the CC-Al2O3 sample, 88±0.1% for the PB-Al2O3 adsorbent, and 98±0.2% for the OP-Al2O3 sample, confirming the suitability of these Al2O3-modified biomasses for the removal of heavy metal ions.
Źródło:
Journal of Water and Land Development; 2021, 49; 29-34
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Removal of Cadmium using Alkaline-Treated Activated Carbon from Leucaena Leucocephala Biomass
Autorzy:
Ibrahim, W. M. H. W.
Sulaiman, Nurul Syuhada
Amini, Mohd Hazim Mohammad
Kadir, W. R. A.
Mohamed, Mazlan
Ramle, Sitti Fatimah Mhd
Bilgin, Ugur
Rahman, Wan
Powiązania:
https://bibliotekanauki.pl/articles/2125550.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
activated carbon
cadmium
Leucaena leucocephala
adsorption
Opis:
Water contamination that caused by heavy metals is a very common phenomenon in the industrial age. One of the popular way to treat metal contaminated water is by adsorption process using activated carbon as the adsorbent. This paper works on producing activated carbon by chemical means with impregnation ratios of NaOH:char (w/w) was predetermined at 1:1 (ACT1-1), 2:1 (ACT2-1) and 3:1 (ACT3-1) under activation temperature of 700°C. Considering the Leucaena leucocephala is a wildly, easy and fast grown species, with the availability throught the year, it was chosen to be used as the precursor. The properties of these activated carbons and its potential for cadmium removal from aqueus solution was analyzed. It was found that the highest surface area was recorded at 662.76 m²/g. Four parameters were studied which are contact time, the effect of pH, initial concentration of adsorbate and temperature. The equilibrium time was achieved in 40 min treatment at initial concentrations of 30 mg/l. The adsorbent exhibited good sorption potential for cadmium at pH 8.0 and equilibrium temperature of 30℃. Based on the results, this study had proved that activated carbon from Leucaena leucocephala biomass have the good potential to be used for removal of cadmium from wastewater.
Źródło:
Archives of Metallurgy and Materials; 2022, 67, 3; 1033--1036
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Metody usuwania jonów kadmu i ołowiu z roztworów wodnych
Methods of cadmium and lead ions removal from aqueous solutions
Autorzy:
Kasprzyk, P.
Sanak-Rydlewska, S.
Powiązania:
https://bibliotekanauki.pl/articles/394659.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN
Tematy:
wymiana jonowa
jony kadmu
jony ołowiu
Purolite C160
ion exchange process
cadmium ions
lead ions
Opis:
W pracy zostaną przedstawione metody eliminacji jonów kadmu i ołowiu z roztworów wodnych. Wśród nich wymiana jonowa staje się coraz popularniejszą metodą usuwania zanieczyszczeń ze ścieków przemysłowych. Za tą metodą przemawiają: prostota procesu, niska energochłonność oraz możliwość selektywnego rozdziału zanieczyszczeń. Wymieniacz jonowy używany w procesie można wielokrotnie stosować, bowiem można go poddawać regeneracji. Stosowanie kolumn jonowymiennych umożliwia także budowę modułową linii technologicznej oczyszczania ścieków oraz szybką wymianę modułów według potrzeb technologicznych i składu ścieków. Wymianę jonową można rozpatrywać jako proces membranowy, gdzie membraną jest powierzchnia ziarna – będąca selektywnie przepuszczalną dla wymienianych jonów. W artykule przedstawiono badania laboratoryjne dotyczące wpływu wybranych parametrów procesu na wydajność wymiany jonowej dla jonów kadmu i ołowiu. Pierwiastki te według polskiego prawodawstwa uznane są za substancje szczególnie szkodliwe i mają działanie kancero- i mutagenne. Najwyższa koncentracja tych pierwiastków występuje na terenach uprzemysłowionych oraz na terenach miejskich. Mogą one pochodzić z przemysłu metalurgicznego, produkcji baterii i akumulatorów, ze spalania paliw kopalnych lub produkcji tworzyw sztucznych. Emisja kadmu i ołowiu do środowiska wodnego odbywa się poprzez odprowadzanie wód kopalnianych czy ścieków z przemysłu hydrometalurgicznego lub z galwanizerni. Badania własne wskazują, że eliminacja jonów Pb i Cd najkorzystniej zachodzi w roztworach o pH około 4 i utrzymuje się na wysokim poziomie w zakresie kwaśnego środowiska. Jonit Purolite C-160 umożliwia osiągnięcie współczynnika wydzielania (X) około 99% dla kadmu – tabela 1, natomiast współczynnik ten dla jonów ołowiu nie przekracza 97% – tabela 2.
This article presents the methods of cadmium and lead ions removal from aqueous solutions. The ion exchange method is becoming a more and more popular method of removing impurities from wastewater. The main advantages of this method are: process simplicity, low energy consumption and the possibility of the selective separation of pollutants. The ion exchanger used in the process could be regenerated, therefore, it could be used repeatedly. The use of ion-exchange columns also allows for the modular construction of the process line and the rapid replacement of modules according to the technological needs and composition of the wastewater. Ion exchange can be seen as a membrane process in which the grain surface acts as a membrane – which is selectively permeable to the exchanged ions. The article presents laboratory studies on the influence of the ion exchange process parameters on the efficiency of cadmium and lead ion exchange. These elements are suspected of carcinogenicity and teratogenicity, and according to Polish Legislation, are considered to be harmful substances. The highest concentration of these elements occurs in industrialized areas and in urban areas. They may come from the hydrometallurgical industry, the production of batteries and accumulators from the burning of fossil fuels and the production of plastics. The emission of cadmium and lead into the aquatic environment is done through the discharge the mine water and wastewater from the hydrometallurgical industry and from electroplating. Experiments show that the elimination of Pb and Cd ions preferably occurs in aqueous solutions with a pH around 4. Ion exchange resin Purolite C-160 allows a removal coefficient (X) in the range of about 99% for cadmium to be achieved – Table 5.1, while the same coefficient for lead ions does not exceed 97% – Table 5.2.
Źródło:
Zeszyty Naukowe Instytutu Gospodarki Surowcami Mineralnymi i Energią PAN; 2016, 94; 205-215
2080-0819
Pojawia się w:
Zeszyty Naukowe Instytutu Gospodarki Surowcami Mineralnymi i Energią PAN
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lead(II) removal from aqueous solutions by solvent extraction with tetracarboxylresorcin[4]arene
Autorzy:
Konczyk, J.
Kozlowski, C.
Walkowiak, W.
Powiązania:
https://bibliotekanauki.pl/articles/110670.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
solvent extraction
lead(II)
zinc(II)
cadmium(II)
resorcinarene
Opis:
A novel tetracarboxylresorcin[4]arene was synthesized and its selective complexing ability towards Pb(II) ions was examined. The influence of several parameters such as pH of aqueous phase, agitation time, extractant and modifier concentrations on solvent extraction of Pb(II) ions from the aque-ous nitrate phase into chloroform organic phase was studied. The stoichiometry of the formed metal-ligand complexes was established by slope analysis. Pb(II) ions were quantitatively extracted in the form of 2:1 Pb(II)-resorcin[4]arene complex from aqueous solutions of pH 5.5 to the solution of ligand in chloroform. Competitive solvent extraction experiments in the presence of Zn(II) and Cd(II) ions were also carried out and high selectivity of the extractant towards Pb(II) over Zn(II) and Cd(II) was found. The selectivity order was: Pb(II) >> Cd(II) > Zn(II).
Źródło:
Physicochemical Problems of Mineral Processing; 2013, 49, 1; 213-222
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ocena możliwości zastosowania szkieł wodnych sodowych do usuwania najbardziej toksycznych metali: Pb, Hg, Cd z zanieczyszczonych ekosystemów wodnych
Assessment of possibility of using sodium liquid glass for removal of the most toxic metals: Pb, Hg, Cd from contaminated ecosystems
Autorzy:
Koźlak, W.
Powiązania:
https://bibliotekanauki.pl/articles/1287209.pdf
Data publikacji:
2010
Wydawca:
Stowarzyszenie Inżynierów i Techników Przemysłu Chemicznego. Zakład Wydawniczy CHEMPRESS-SITPChem
Tematy:
szkło wodne sodowe
azotany ołowiu (II)
azotany rtęci (II)
azotany kadmu (II)
badania turbidymetryczne
toksyczność metali
sodium liquid glass
lead (II) nitrates
mercury (II) nitrates
cadmium (II) nitrates
turbidimetric tests
toxicity of metals
Opis:
Scharakteryzowano trzy najbardziej toksyczne metale (Pb, Hg i Cd), uwzględniając ich wpływ na organizmy i środowisko. Zaproponowano metodę turbidymetryczną, polegającą na otrzymywaniu rozpuszczonego koloidalnego krzemianu, dla oceny możliwości wykorzystania szkieł wodnych do usuwania toksycznych metali Pb i Cd z zanieczyszczonych mediów wodnych. Z przebiegu krzywych zmętnienia wynika, że - z wyjątkiem soli Hg (II) - we wszystkich przypadkach wartości zmętnienia w układach z jonami Pb2+ rosną w czasie, natomiast krzemian kadmu powstaje natychmiast w czasie t = 0 i nie ma dalszego przyrostu zmętnienia w czasie. Charakter krzywych zmętnienia związany jest z rodzajem krzemianu tj. jego modułem krzemianowym. Stwierdzono, że szkła wodne sodowe można zastosować do oczyszczania mediów wodnych z najbardziej toksycznych pierwiastków (Pb i Cd). W przypadku soli rtęci (II) proponowana metoda jest zawodna.
Three most toxic metals (Pb, Hg and Cd) were characterized, considering their impact on organisms and environment. Turbidimetric method that consists in obtaining of dissolved colloidal silicate for assessment of possibility of using liquid glasses for removal of toxic metals Pb and Cd from contaminated water media has been suggested. From time process of turbidity curves it results that, with exclusion of Hg (II) salts - in the systems with Pb2+ ions, in all cases turbidity values increase in time, but cadmium silicate is forming instantly in time t=0 and there is no further increase of turbidity in time. Character of turbidity curves is associated with type of silicate i.e. its silicate module. It was found that sodium liquid glasses can be used to remove most toxic elements (Pb and Cd) from water media. In the case of mercury (II) salts, the suggested method is fallible.
Źródło:
Chemik; 2010, 64, 6; 452-461
0009-2886
Pojawia się w:
Chemik
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ pola ultradźwiękowego na adsorpcję kationów kadmu
The Effect of Ultrasonic Field on the Adsorption of Cadmium Ions
Autorzy:
Lach, J.
Okoniewska, E.
Stępniak, L.
Ociepa, E.
Powiązania:
https://bibliotekanauki.pl/articles/1819171.pdf
Data publikacji:
2013
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
pola ultradźwiękowe
adsorpcja kationów
aqueous solution
activated carbon
sewage sludge
metal ions
removal
surface
Opis:
Adsorption on activated carbon is one of the methods applied for removal of heavy metals from water and wastewater contaminated with these elements. Ion exchange is a predominating mechanism in the process of sorption of ions. In case of sorption of heavy metals cations various surface aggregates are formed. Other processes, such as reduction and oxidation, and precipitation in the pores of insoluble compounds (e.g. hydroxides, carbonates) also occur. The processes behind the formation of aggregates with various degrees of resistance have a particular effect on the selectivity of ion exchange on activated carbons. The chemical composition of activated carbon surface – in particular, the presence of oxygen groups capable of ion exchange – shows the most significant effect during adsorption of heavy metals ions. Typically, the surface of the activated carbons produced with the steam-gaseous method has functional groups both of acidic and alkaline character that are capable of exchanging cations as well as anions. Carbon materials with no functional groups can also sorb protons. This is possible due to the fact that dislocated electrons π in the solutions act as Lewis base. There are a number of methods currently being investigated that would allow for improving the efficiency of adsorption of heavy metals. In the presented work the effect of ultrasonic field on the adsorption of cadmium from the model solutions was analyzed. Various configurations of ultrasonic field applied in the process of adsorption were investigated. Ultrasounds were generated in the UP 400S disintegrator. In the first phase the activated carbon in the form of granules was modified with the ultrasonic field of acoustic power density of 42,5 W/cm2or 85,0 W/cm2, at the amplitude of 30 and 60 µm, and at the exposure time of 5, 10, 15 and 20 min. Modified activated carbons were used for sorption of cadmium ions from the solutions at the initial concentrations ranging from 2,24 do 11,2 mg/dm3. The adsorption of cadmium on the activated carbon modified with ultrasounds (at the amplitude of 30 µm and 60 µm) and at the shortest exposure time (i.e. 5 min.) was higher than on the initial activated carbon. The most favorable results were obtained for the activated carbon modified with ultrasonic field with the acoustic power density of 42,5 W/cm3 and the exposure time of 10 min. The efficiency of cadmium adsorption for the highest concentration increased from 50% (the initial activated carbon) to 63%. Also, the work included the analysis of the effect of ultrasonic field on the cadmium solution with the activated carbon in the form of granules in the first phase of static adsorption. In this case, no significant differences in the adsorption capacities were observed. Also, the effect of ultrasounds on the solution used for the adsorption of cadmium did not have an impact on the efficiency of adsorption. In the final phase of the investigations the effect of sonification on the adsorption of cadmium on the powdery activated carbon was analyzed. The control sample was mechanically mixed for 5 min, and the remaining samples were subjected to the ultrasonic field at various amplitudes but with the same exposure time. The efficiency of adsorption combined with ultrasounds was significantly higher. The final concentrations during the adsorption without ultrasounds were in the range of 0,291 to 1,778 mg/dm3 whereas for the adsorption combined with ultrasounds these concentrations ranged from 0,13 to 0,748 mg/dm3.
Źródło:
Rocznik Ochrona Środowiska; 2013, Tom 15, cz. 3; 2142-2157
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Potassium Hydroxide Activated Peanut Shell as an Effective Adsorbent for the Removal of Zinc, Lead and Cadmium from Wastewater
Autorzy:
Maki, Rusol
Qasim, Bashar
Powiązania:
https://bibliotekanauki.pl/articles/2202316.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
adsorption
activated peanut shell
heavy metals
wastewater
Opis:
The toxic heavy metals, as non-biodegradable pollutants, have become a serious threat to aquatic environment. This study aimed to assess the efficiency of the low cost, available and environment-friendly peanut shell as an effective adsorbent for the removal of Zn, Pb and Cd from wastewater. The peanut shell was prepared by carbonization by pyrolysis process at 550 °C, activated with 7M potassium hydroxide(KOH) at 750 °C, and then characterized by using Scanning Electron Microscopy (SEM), and Fourier Transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) surface area analysis. The optimum conditions for metal ions adsorption were investigated as a function of various parameters. The optimum conditions included: pH of 6, initial metal concentrations of 20 mg/l for Pb and Zn as well as 40 mg/l for Cd, adsorbent mass of 2 g, optimum temperature of 45 °C and the preferable contact time of 60 min. The removal percent for the studied metal ions exceeded 98%. The adsorption isotherm showed that the Langmuir model was the best fitted model for the metal ions adsorption onto activated peanut shell surface, and the kinetic of adsorption followed the pseudo-first order model. The obtained results showed that the KOH-activated peanut shell possess higher adsorption efficiency for the removal of the studied metal ions from wastewater.
Źródło:
Journal of Ecological Engineering; 2023, 24, 1; 66--78
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 20

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