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1

Study on the treatment of fluorine-containing wastewater by precipitation-adsorption process

Li Xiaochang, Lyu Xianjun

Environment Protection Engineering

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2023

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Vol. 49, nr 2

55--73

EN

Fluorine-containing wastewater from the Yuncheng Sewage Treatment Plant in Heze City, Shan-dong Province was treated by coagulation and precipitation with poly aluminum sulfate, and CaO chemical precipitation-activated carbon adsorption, with a view to reducing fluoride ions concentration in the wastewater to below the discharge standard. The results showed that the optimum conditions for the coagulation-sedimentation test of poly aluminum sulfate were as follows: the dosage of poly aluminum sulfate 0.3 g/dm3, initial pH value 4.0, the removal rate of fluoride ion in the fluorine-containing wastewater reached 98.46%, and the concentration of fluoride ion was 0.462 mg/ dm3, which reached the discharge standard (1.5 mg/ dm3); The optimum conditions for the CaO chemical precipitation, and lanthanum loaded activated carbon adsorption method were as follows: the amount of CaO 20 g/ dm3, initial pH of the chemical precipitation test 8.0, the dosage of lanthanum loaded activated carbon 10 g/ dm3, and the initial pH of the adsorption test 6.0. At this time, the removal rate of fluoride ions in the fluorine-containing wastewater reached 95.81%, and the concentration of fluoride ions was 1.26 mg/ dm3, which also met the discharge standard.

2

Wykorzystanie wysokorozdzielczej absorpcyjnej spektrometrii cząsteczkowej z piecem grafitowym jako reaktorem do oznaczania fluoru w próbkach biologicznych

Gawor Andrzej, Tupys Andrii, Ruszczyńska Anna, Bulska Ewa

Analityka : nauka i praktyka

|

2022

|

nr 1

4--8

PL

Opracowano i zwalidowano procedurę analityczną oznaczania śladowych ilości fluoru w próbkach biologicznych przy użyciu molekularnej absorpcji cząsteczki GaF. Zwalidowana procedura analityczna pozwala na oznaczenie małej ilości fluoru bezpośrednio po mineralizacji próbek biologicznych kwasem, co nie było możliwe innymi metodami.

3

Fluorowany motyw w aktywnych biologicznie peptydomimetykach

Koroniak-Szejn Katarzyna, Rapp Magdalena

Wiadomości Chemiczne

|

2020

|

[Z] 74, 3-4

145--179

EN

Incorporation of fluorine atom or fluoroalkyl group into molecules, often induces a remarkable effect upon the physical and chemical properties leading to significant changes of its reactivity [1-5], therefore this modification is often used in the synthesis of drugs and biologically active compounds [6, 7]. The change in reactivity has far-reaching consequences, affects bond energy in the molecule, acidity and alkalinity, hydrogen bond formation and the geometry of the molecule [1-5]. The change in acid-base properties and polarity forced by a fluorine or fluorinated motif in the modified amino acid or peptide molecule has already found numerous applications in bioisosteric mimetics [9]. In addition, using a fluorine atom as a probe, conformation determination and stereochemistry of receptor interaction become more effective due to the possibility of using 19F NMR spectroscopy. The stereoselective introduction of fluorine atoms can therefore be exploited as a conformational tool for the synthesis of shape-controlled functional molecules. Particular attention has been paid to fluorinated peptidomimetics due to the huge variety of their biological activity. Proteins play a significant role in drug design and synthesis. Peptide binding in living organisms is quite labile which is associated with the presence of proteolytic enzymes. Therefore, to prevent protein hydrolysis, new, modified compounds are thought to mimic the properties and functions of peptide bond. These types of compounds are called peptidomimetics. In this monograph, we will focus on the biologically active fluorinated peptidomimetics, in which the amide bond has been replaced by a fluorinated group and thus they can "mimic" peptide bond functions (pseudopeptides). Other peptidomimetics with typical amide bond, but in which the remaining part of the molecule has been modified by introducing a fluorinated group or fluorine (peptide analogs) will also be discussed. The main goal of this work, however, is to demonstrate the beneficial effect of fluorine on the properties of the modified compounds and associated with it consequences. The superior goal of this work, however, is to demonstrate the unique effect of fluorine on the properties of the target compounds and in the design of higher order structures reflecting a more sophisticated molecular construction that broadens biological mimesis.

4

Fluorowane aminofosfoniany

Cytlak Tomasz, Kaźmierczak Marcin

Wiadomości Chemiczne

|

2020

|

[Z] 74, 3-4

203--230

EN

Aminophosphonates and aminophosphonic acids are important substrates in the study of biochemical processes. They have found a wide range of applications as enzyme inhibitors, agrochemicals and pharmaceuticals in the areas of biological and medicinal chemistry. Due to the unique properties of fluorine atom, such as high electronegativity and electron density, its presence in aminophosphonates’ moiety can influence chemical reactivity, biological activity, metabolic stability, chemical bonding ability and solubility. Recently, special interest has been focused on synthesis of fluorinated aminophosphonates due to their promising applications in the fields of bioorganic chemistry. Many of these compounds exhibit antitumor, antibacterial and antifungal activities [1-3].

5

A novel method for purification of phosphogypsum

Wang Jinming, Dong Faqin, Wang Zhaojia, Yang Feihua, Du Mingxia, Fu Kaibin, Wang Zhen

Physicochemical Problems of Mineral Processing

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2020

|

Vol. 56, iss. 5

975--983

EN

Phosphogypsum is an industrial solid waste from the phosphate fertilizer industry. At present, the accumulation of phosphogypsum has caused very serious economic and environmental problems. A large scale of phosphogypsum is consunmed in the building field. The characteristics of whiteness and phosphorus content are important factors affecting the use of phosphogypsum as a building material. In this study, soluble phosphorus and fluorine were removed by adding lime, and flotation was employed to purify phosphogypsum. A large amount of organic matter and fine slime in the phosphogypsum were removed by reverse flotation, and gypsum was floated by positive flotation. Through the flotation closed-circuit experiment, the whiteness of phosphogypsum was increased from 31.5 to 58.4, the percentage of total phosphorus in gypsum (P2O5) was reduced from 1.78 to 0.89, the grade of calcium sulphate dihydrate was 96.6%, the recovery of concentrate was 74.1%. After removing impurities, the phosphogypsum concentrate reached the first grade national standard of the phosphogypsum building materials in China. The method is cheap and practical, and can be used as an important method for pretreatment of phosphogypsum.

6

Nuclear reaction applied to fluorine depth profiles in human dental tissues

Torrisi Lorenzo

Polish Journal of Medical Physics and Engineering

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2019

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Vol. 25, Iss. 4

193--199

EN

The nuclear reaction 19F(p, αγ)16O is presented as a valid method to measure the fluorine content in the first superficial layers of teeth. The analysis is performed in-vitro in extracted teeth, both healthy, fluorotic and decayed. It is performed irradiating the tooth with an energetic proton beam and analyzing the emitted high energy alpha particles. The quantitative analysis is performed comparing results with that of a standard sample at a known concentration. The depth profile of fluorine has a maximum content in the first superficial layers. The average concentrations in healthy enamel are of the order of 2 mg/g; it is of about 10 mg/g in fluorotic teeth, and below 0.1 mg/g in decayed teeth. The concentration in the dentine is about 50% lower than in the enamel and the concentrations decrease going from incisors to premolar and to molar teeth. Many results and a literature comparison are presented and discussed.

7

Oznaczanie fluoru w żywności i produktach codziennego użytku. Cz. 1

Palak Ewelina, Godlewska-Żyłkiewicz Beata

Analityka : nauka i praktyka

|

2019

|

nr 2

34--38

PL

Metody oparte na elektrodach jonoselektywnych jako pierwsze zastosowano do oznaczania fluoru. Do dziś są one najczęściej wykorzystywane ze względu na szybkość, prostotę oraz względnie nieduże koszty pomiarów.

8

Oznaczanie fluoru w żywności i produktach codziennego użytku. Cz. 2 - wysokorozdzielcza absorpcyjna spektrometria cząsteczkowa HR CS MAS

Palak Ewelina, Godlewska-Żyłkiewicz Beata

Analityka : nauka i praktyka

|

2019

|

nr 3

28--32

PL

Zaletami metody HR CS MAS są wysoka czułość, niskie granice wykrywalności, szeroki zakres liniowości oraz ograniczenie przygotowania próbki di minimum, a także odporność na interferencje. Z tego powodu można przypuszczać, że wysokorozdzielcza absorpcyjna spektrometria cząsteczkowa z ciągłym źródłem promieniowania może stać się coraz powszechniej stosowaną techniką oznaczania fluoru w laboratoriach analitycznych.

9

Assessment of iron oxide and local cement clay as potential fluoride adsorbents

Atasoy A. D., Yesilnacar M. I.

Environment Protection Engineering

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2017

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Vol. 43, nr 2

109--118

EN

Health problem from fluoride contaminated water is more acute in rural and small urban communities. Defluoridation of low contaminated water by inexpensive adsorbents is a substantial practice worldwide. In the study, low-cost sorbents have been investigated as replacements for current costly methods of removing the excess fluoride from water below the certain concentration. The adsorption capacity of iron oxide and cement clay in fluoride removal was investigated by the batch method. The equilibrium time was attained in 3 h and 2 h for iron oxide and cement clay, respectively. Optimum adsorbent dosage was found to be 5 g/dm3. Initial fluoride concentrations for the adsorption studies were 1.24 and 12.2 mg/dm3. Fluoride adsorption isotherm fitted well the Freundlich isotherm with the coefficient of determination >0.99 for both adsorbents. The fluoride adsorption capacity of iron oxide was found higher than that of cement clay due to the high surface area and charge of iron oxide. How-ever both substances can reduce F– contamination below the acceptable limits of 1.5 mg/dm3 for less contaminated water.

10

Fluor (F-) w wodach termalnych Cieplic Śląskich

Kiełczawa B.

Górnictwo Odkrywkowe

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2016

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R. 57, nr 1

16--22

PL

W artykule omówiono zawartości jonów fluorkowych w poszczególnych ujęciach wód termalnych w Cieplicach Śląskich. Określono stopień nasycenia omawianych wód względem głównych minerałów skałotwórczych i prawdopodobnych produktów ich wietrzenia. Omawiane wody termalne są przesycone fluorytem. Przedstawiono analizę zależności pomiędzy głównymi składnikami wód i jonami F. Podjęto próbę określenia pochodzenia fluorków obecnych w wodach termalnych Cieplic Śląskich.

EN

The article describe the contents of fluoride ions in particular intakes of thermal waters in Cieplice Śląskie. The saturation state for main minerals and their possible weathering products is shown and the thermal water is found out to be saturated for fluorite. The analysis of the relationship between the main components of water and ions F-fluorite. The analysis of the relationship between the main components of water and ions F-fluorite. The analysis of the relationship between the main components of water and ions F was presented. An attempt to determine the origin of fluoride in thermal waters of Cieplice Śląskie was made.

11

Fluor w wodach podziemnych i powierzchniowych w okolicy Skawiny k. Krakowa

Górnik M.

Przegląd Geologiczny

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2015

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Vol. 63, nr 7

397--403

EN

The paper presents the examination of fluorine concentration in groundwater and surface water in the Skawina region, including the determination of the influence of a former aluminum smelter plant on the concentration. Although the Skawina aluminum smelter emitted the largest amounts of fluorine-containing dust and gases in 1954–1981, the persistent low concentration of fluorine in groundwater was found during the present examinations. The results from 2011 are similar to those conducted in the 1970s and 1980s. In a water reservoir located below the closed landfill, high fluorine concentrations were recorded (103.69 mg dm3), which means that fluorine has been eluted out of the landfill.

12

Wykorzystanie spektrometrii fluorescencji rentgenowskiej (XRF) do oznaczania fluoru w formie fluorku wapnia

Kowalkiewicz Z., Urbaniak W.

Ekologia i Technika

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2014

|

R. 22, nr 3

98--105

PL

Istnieje kilkanaście metod analitycznych oznaczania fluoru w próbkach stałych, jednak umożliwiają one tylko analizę fluoru w formie jonów fluorkowych, dlatego też konieczne jest przeprowadzenie fluoru w formę jonową, często przy użyciu pracochłonnych i czasochłonnych metod przygotowania próbek do analiz. Z tego powodu zaproponowano pośrednią metodę oznaczania fluoru za pomocą spektrometrii fluorescencji rentgenowskiej (XRF) będącą modyfikacją Polskiej Normy PN-70 H-04132 dotyczącej oznaczania fluoru w fluorycie (CaF2). Oznaczenie końcowe wapnia może być przeprowadzane za pomocą techniki spektrometrii XRF lub jej odmiany- spektrometrii fluorescencji rentgenowskiej całkowitego odbicia (TKRF). Dzięki zastosowaniu techniki XRF możliwe jest osiągniecie wyższej dokładności i precyzji oznaczeń wapnia niż w przypadku stosowania Polskiej Normy PN-70 H-04132 [11]. Nowa procedura analityczna umożliwia znaczne uproszczenie tej normy poprzez zmniejszenie ilości jej etapów. Nowa metoda jest szybką, prostą i stosunkowo tanią metodą analityczną analizy próbek stałych, w których fluor obecny jest w formie nieorganicznych i nierozpuszczalnych w wodzie soli. Znajduje ona zastosowanie w przemyśle chemicznym, metalurgicznym, ceramicznym i szklarskim oraz jest niezbędna do wdrożenia metod zagospodarowania odpadów zawierających nieorganiczne i nierozpuszczalne w wodzie związki fluoru.

EN

There are over than dozen analytical methods of fluorine determination in solid samples. However, they are only dedicated to determinate fluorine in the form of its anions therefore it is necessary to obtain them by time-consuming and labour-consuming methods of samples preparation. For this reason, the indirect method of fluorine determination with the use of X-ray fluorescence spectrometry (XRF) has been devised. This method is the modification of procedure according to the Polish Standard PN-70 H-04123 [11] that deals with a fluorine determination in fluorite. The final determination is carried out with the use of XRF spectrometry or its type- total reflection X-ray fluorescence spectrometry (TXRF). Owning to this, the proposed modifications lead to a higher accuracy and precision of results in comparison with the standard's procedure. The new analytical procedure enables to simplify considerably this procedure according to the standard because a few sample preparation steps were removed. The new method is a quick, easy and relatively low-cost procedure for solid samples determination consisting of fluorine in the form of insoluble in water inorganic salts. The applications of this method are found not only in a chemical, metallurgical, ceramic and glassware industry, but also it is essential for introducing utilisation methods of waste that contains fluorine in the form of insoluble in water inorganic salts.

13

Defluoridation of drinkable water Comparative study and parameter influent

Atia D., Hoggui A., Abdelhafidh B. A.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 10, iss. 1

48-60

EN

El-Oued is known for some diseases caused by fluoride concentration in drinkable water. To reduce it , a sample with the biggest content among many sources was chosen. A comparative study between the precipitation with calcium salts [Ca(OH)2, CaCl2, CaSO4] and the coagulation with the following salts [Al2(SO4)2•18H2O, Fe2(SO4)2•H2O, FeSO4] was done. Finely we studied the parameters influencing (the mass , pH, temperature) to choose the best conditions in order to get better reduction yield.

14

Comparative study for the defluoridation of water by Coagulation

Atia D., Hoggui A., Abdelhafidh D. B. A.

International Letters of Chemistry, Physics and Astronomy

|

2013

|

Vol. 8, iss. 2

123-131

EN

El-Oued is known for some diseases caused by fluoride concentration in drinkable water. To reduce it, we have chosen a sample with the highest content of fluoride among many sources in order to coagulate it with Al2(SO4)3ź18H2O, Fe2(SO4)3źH2O and FeSO4. In order to get better reduction yield of fluoride, a study has been done on the influencing parameters (concentration, pH, temperature) to choose the best conditions. The remove of fluoride is favorable at low concentration of Al2(SO4)3, at room temperature and normal acidity.

15

Method of simultaneous measurement of total sulfur, chlorine and fluorine content in biogas

Gaj K., Cybulska H., Knop F.

Environment Protection Engineering

|

2011

|

Vol. 37, nr 1

23-30

EN

The method of determination of total content of sulfur, chlorine and fluorine compounds in biogas has been implemented and verified at real conditions. The laboratory plant and the results of periodical measurements of the composition of biogas have been described. The main effects of the research are: determination of the range of concentrations for the analysed compounds in a typical biogas from sewage sludge digestion and evaluation of average fraction of sulfur from hydrogen sulfide in total sulfur content during multiannual period.

16

Ultra-płytka implantacja fluoru z plazmy w.cz. jako metoda poprawy właściwości elektro-fizycznych struktur MIS z dielektrykami bramkowymi wytwarzanymi metodą PECVD

Kalisz M., Mroczyński R., Beck R. B.

Elektronika : konstrukcje, technologie, zastosowania

|

2011

|

Vol. 52, nr 2

20-26

PL

W pracy przedstawiono analizę zmian parametrów elektrycznych i niezawodnościowych, jakie wprowadza obecność bogatej we fluor warstwy w strukturze bramkowej układu MOS (MIS] z dielektrykami bramkowymi wytwarzanymi metodą PECVD. Powierzchnia podłoży krzemowych przed wykonaniem struktur testowych poddana została odmiennie, niż spotyka się to najczęściej w literaturze, procesom ultra-płytkiej implantacji jonów z plazmy CF₄. Uzyskane wyniki wskazują, że badane układy MOS (MIS), wykonane na zmodyfikowanych podłożach krzemowych, charakteryzują się mniejszymi (co do wartości bezwzględnej) wartościami napięcia płaskich pasm (UFB) oraz ładunku efektywnego (Qeff) w porównaniu do struktur referencyjnych. Nie zmienia się natomiast znacząco gęstość stanów powierzchniowych w środku pasma energii zabronionej krzemu (Ditmb). Wprowadzenie fluoru w obszar graniczny półprzewodnik/dielektryk struktur MOS (MIS) powoduje w konsekwencji także nieznacznie zmniejszenie wartości przenikalności elektrycznej warstw dielektrycznych.

EN

In this work, the analysis of changes in electro-physical and reliability properties, which introduce fluorine-rich dielectric layer formed in the gate of MOS (MIS] structures with PECVD dielectric layers, has been reported. In contrary to commonly found in literature ways, ultra-shallow fluorine implantation from CF₄ plasma of silicon substrates, before the fabrication of test structures, was performed. Presented results have shown, that investigated MOS (MIS) structures, fabricated on modified silicon substrates, are characterized by lower (in absolute values) flat-band voltage (UFB) and effective charge (Qeff) values in comparison to reference structures. Moreover, interface states density in the middle of silicon forbidden band values (Ditmb do not seem to differ significantly In consequence, introduction of fluorine into the semiconductor/dielectric interface of MOS (MIS] structure results in a small decrease of permittivity constant of PECVD dielectric layers.

17

Wpływ zawartości fluoru na właściwości powłok osadzanych w wyładowaniu barierowym pod ciśnieniem atmosferycznym

Rżanek-Boroch Z., Buczek M., Ilik A., Kosiński A.

Przemysł Chemiczny

|

2010

|

T. 89, nr 9

1209-1211

18

Environmental aspects of feed phosphates production

Hoffmann J., Hoffmann K., Borowiec M., Huculak M.

Polish Journal of Chemical Technology

|

2009

|

Vol. 11, nr 1

16-19

EN

The risks resulting from the selected feed phosphates application in animal nutrition were analyzed. The results of the analyses of the fodder phosphates obtained in laboratory conditions were presented, including the toxic and disadvantageous substances with regard to their impact upon the environment.

19

Influence of the Combinated Bioaccumulation of Fluoride and Sulfur on Chlorophyll Content in Needles of Selected Trees from the Areas of Southern Poland

Sochacka J., Kusa Z., Baran W.

Ecological Chemistry and Engineering. A

|

2009

|

Vol. 16, nr 4

427-432

EN

It was the fluorine (F), sulfur (S) and chlorophyll (Chl) content that was determined in the needles of conifer species: European spruce (Picea abies), Colorado spruce (Picea pungens), Scots pine (Pinus silvestris L.) and Common silver (Abies alba). The materials were collected in the regions located in the vicinity of steel and power engineering industry impact and in a place situated in a non-industrial area. The obtained results were analyzed from the viewpoint of the relationships between the S, F and chlorophyll content. From the findings, it appears that, accumulation of F and S in needles only in case of Scots pine has been accompanied by more evident decrease in the Chl content. In the case of remaining conifer species increased accumulation of F and S in older needles did not influence the Chl content therein.

PL

Zawartość siarki (S) i fluoru (F) oraz chlorofilu (Chl) oznaczano w igłach świerka pospolitego (Picea abies), świerka kłującego (Picea pungens), sosny pospolitej (Pinus syhestris) i jodły pospolitej (Abies alba). Materiał do badań pobierano w miejscowości Strzemieszyce, Ustroń Polana (Beskid Śląski) i Zebrzydowice (powiat cieszyński) znajdujących się w strefach oddziaływania zanieczyszczeń z ośrodków przemysłowych Polski i zanieczyszczeń transgranicznych oraz w miejscowości Brzeźna położonej koło Nowego Sącza. Uzyskane wyniki analizowano z punktu widzenia zależności pomiędzy zawartością S i F i zawartością chlorofilu w igłach. Spośród badanych gatunków drzew iglastych jedynie w przypadku igieł sosny pospolitej stwierdzono zmniejszenie zawartości chlorofilu związane z akumulacją F i S.

20

Fate of Air Pollutants from Konin Industrial Complex in Pine Forest Ecosystems

Staszewski T., Kubiesa P., Błocka A.

Ecological Chemistry and Engineering. A

|

2009

|

Vol. 16, nr 4

441-449

EN

In agricultural area of Konin where previously no industrial activity was performed the complex of power stations combusting brown coal was built in the end of the fifties followed by the aluminium smelter which was put into operation in 1965. Both these industrial works emit considerable amounts of phytotoxic gases (F2, SO2, NO2). Aluminium smelter emits vast amount of fluorine as aluminum is produced by thermoelectrolysis of aluminum oxide in electrolyte consisting of cryolite and aluminum fluoride as well as it is a major emitter of PAHs due to carbon electrode "combustion". Because these plants did not meet technology parameters and production was poorly controlled in first period of activity harmful effects of their emission in the natural environment were observed. Beginning from the nineties intensive proecological efforts were made and intensive modernization of the plants was performed. All these activities resulted in a significant reduction of air pollutants emission. The paper presents the results of investigation carried out in the monitoring net established in Konin area. The fate of air pollutants currently emitted and deposited to the soil within a long period of the plants activity was determined. The vacuum ceramic cup lysimeters were used to assess the concentration and hazard of inorganic and organic chemicals for water - soil environment. On the basis of differences in concentration of cations and anions the rate of nitrification and acidification processes in the soil was also analysed.

PL

W otoczeniu Konina na obszarze typowo rolniczym, gdzie uprzednio nie prowadzono działalności przemysłowej, na początku lat pięćdziesiątych, wykorzystując węgiel brunatny z kopalni odkrywkowych uruchomiono kompleks elektrowni PAK (Pątnów, Adamów, Konin), a w roku 1966 oddano do eksploatacji Hutę Aluminium "Konin". Zakłady te emitowały znaczne ilości gazów fitotoksycznych (F2, SO2, NO2). Huta aluminium emituje duże ilości fluoru, ponieważ aluminium produkowane jest w procesie termoelektrolizy tlenku glinu w elektrolicie zawierającym kriolit i fluorek glinu, jak również jest znaczącym emiterem WWA (PAHs) powstających w wyniku "spalania" elektrod węglowych. Ze względu na to, że zakłady przemysłowe w początku swej działalności nie spełniały wymaganych parametrów technologicznych, a emisje do atmosfery gazów odlotowych były niewystarczająco kontrolowane w środowisku przyrodniczym występowały wyraźnie szkodliwe efekty. W latach dziewięćdziesiątych podjęto intensywne działania proekologiczne i modernizacyjne zakładów, które doprowadziły do znacznej redukcji emisji zanieczyszczeń powietrza. W pracy przedstawiono wyniki badań przeprowadzonych w lasach sosnowych znajdujących się w sieci monitoringowej ustanowionej na obszarze Konina. Przedstawiono poziom depozycji zanieczyszczeń do ekosystemów leśnych oraz migrację aktualnie emitowanych zanieczyszczeń i zdeponowanych w glebie w okresie długoletniej działalności zakładów. Do oceny stężeń i zagrożenia środowiska wodno-glebowego związkami organicznymi i nieorganicznymi zastosowane ceramiczne lizymetry próżniowe. Na podstawie różnic w stężeniach kationów i anionów w różnych przedziałach ekosystemu leśnego określono także natężenie procesów nitryfikacyjnych w glebie.