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1

Impact of sampling techniques on the concentration of ammonia and sulfide in pore water of marine sediments

Brodecka-Goluch Aleksandra, Siudek Patrycja, Bolałek Jerzy

Oceanological and Hydrobiological Studies

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2019

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Vol. 48, No. 2

184--195

EN

Three ex situ pore water sampling procedures (I – rhizon samplers, II – centrifugation of sediment subsamples collected from different sediment depths without core sectioning, III – core sectioning and centrifugation of sediment sections) were compared to indicate factors that may affect concentrations of pore water constituents (ammonia and sulfides). The methods were selected and modified in such a way as to determine how the concentrations are affected by different factors related to sampling procedures, e.g. contact with atmospheric air, filtration and sediment core disturbance. They were tested on nine sediment cores collected at one site in the southern Baltic Sea. The concentration of ammonia in pore water from centrifuged sediment sections was significantly higher compared to pore water extracted by rhizons – probably due to the impact of changing pH. The factor with the greatest impact on the H2S/HS– concentration in the analyzed pore water was the contact with atmospheric air and/or the extrusion of sediments from a core liner. Rhizons proved to be the best option for sampling pore waters analyzed for H2S/HS– and NH4+/NH3. In the case of H2S/HS– we noticed the smallest loss of the analyzed constituents. For ammonia, the centrifugation of the whole sediment sections was likely to cause interferences in the indophenol blue method.

2

Speciation of Mercury Contaminant in Public Gold Mine Tailing and its Stabilization Using Sulfur and Sulfide

Trihadiningrum Yulinah, Latif Rezki Amalia, Rachman Ranno Marlany

Journal of Ecological Engineering

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2019

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Vol. 20, nr 4

29--34

EN

The mercury-containing tailing waste from public gold mines in Indonesia is generally deposited on soil without treatment. This research aimed at determining the amount and composition of mercury species in the tailing, and testing the effect of sulfur and sulfide on mercury stabilization. Samples were collected from a tailing pile at different depths in a public gold mine in Kulon Progo, Indonesia. The samples were characterized according to the mercury concentrations and Toxicity Characteristic Leaching Procedure (TCLP) test. Mercury speciation was carried out using nitrogen gas flow into tailing samples, which were placed in three test tubes. The released mercuric species was entrapped in KCl and KmnO4 solutions. The mercury stabilization was carried out using sulfur and sodium sulfide. TCLP test was performed to the stabilization products. The mercury concentrations were measured using a mercury analyzer. The results showed that the mercury in the tailings were dominated by elemental Hgo, the concentrations of which in the tailing piles of 30, 60, and 90 cm depths were 74.7%, 71.6%, and 76.5% respectively. Those of ionic Hg2+ form were 25.3%, 28.4%, and 23.5%, respectively. Additions of sulfur powder and sodium sulfide solution produced stable black-colored mercury sulfide. When compared to sulfide, sulfur was more recommended for stabilizing mercury in the tailing waste.

3

Attempt to Apply Surface-Conductive PAN as a Precursor for aPAN Ionic Electroactive Polymer Gel Fabrication

Żyłka P., Koprowska J.

Fibres & Textiles in Eastern Europe

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2016

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Vol. 24, no. 5 (119)

29--33

EN

Chemically activated polyacrylonitrile (aPAN) displays ionic electro-mechanically active polymer properties. Thin, gel-like fibre is a technically feasible form of aPAN, as it quickly shrinks or swells in response to a variation in electrolyte pH, soaking it in. A prerequisite for direct electrical stimulation of aPAN fibres through electrolysis–produced variations in pH is their electrical conductivity, commonly achieved by complex surface modification of already-formulated aPAN. The paper presents an alternative approach involving the exploitation of electro-conducting surface-modified PAN fibres as a precursor for fabrication of aPAN. The electrical conductivity of precursor PAN fibres was achieved by the chemical formation of a copper sulfide complex covering.

PL

Chemicznie aktywowany poliakrylonitryl (aPAN) wykazuje właściwości elektro-mechanicznie aktywnego polimeru jonowego. Cienkie, żelowe włókna są technicznie pożądaną formą aPAN, gdyż szybko kurczą się lub pęcznieją w odpowiedzi na zmianę pH elektrolitu, w którym są zanurzone. Warunkiem do prowadzenia bezpośredniej stymulacji elektrycznej włókien aPAN poprzez elektrochemicznie wywołane zmiany pH jest uzyskanie ich elektroprzewodnictwa, w klasycznym podejściu osiągane przez złożoną modyfikację powierzchni już po wytworzeniu aPAN. Artykuł przedstawia alternatywne podejście oparte na wykorzystaniu elektro-przewodzących, zmodyfikowanych powierzchniowo włókien PAN (poliakrylonitrylu) jako prekursora do wytwarzania aPAN. Przewodność elektryczną włókien prekursora osiągnięto chemiczne poprzez wytworzenie na ich powierzchni silnie związanych kompleksowo siarczków miedzi.

4

Modeling of Precipitate Oxide and Sulfide Inclusions Formation in Liquid Steel

Didenchuk D., Kalisz D.

Archives of Foundry Engineering

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2015

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Vol. 15, iss. 4 spec.

19--22

EN

The behaviour of non-metallic inclusions MnO, MnS, FeS, Al2O3, SiO2, Y2O3,Y2S3 in liquid steel were modelled in commercial software FactSage. It allowed for calculating and designing diagrams of dependence of inclusions formation from the concentration of yttrium in determined limits of aluminium and oxygen. As a result, the influence of the increasing yttrium concentration on the precipitations of oxide and sulfide inclusions is observed. The behavior of precipitation the another analyzed oxides and sulfides is also observed in liquid steel, giving a full composition in non-metallic inclusions, formatted in specified conditions. The amounts of mass fractions of Y2O3 and Y2S3 are increasing at the growing Y in liquid steel, which shows the active formation of these inclusions.

5

Modifying effect of electron beam irradiation on magnetic property of iron-bearing minerals

Wang H., Lu S.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 1

79--86

EN

The effect of electron beam irradiation on magnetic property of iron bearing minerals was investigated by susceptibility measurements. The results show that the magnetic susceptibility of iron bearing sulfide minerals can be enhanced remarkably by strong beam current irradiation, while the magnetic susceptibility of oxidized iron minerals keeps unchanged and even is slightly reduced. The magnetic susceptibility of arsenopyrite can reach the ferromagnetic level. The particle size of irradiated minerals makes notable effects on magnetic susceptibility. The magnetic susceptibility of irradiated minerals is enhanced greatly with reduction of particle size, and the irradiation dose corresponding to the maximum magnetic susceptibility is decreased simultaneously. Exposure of pyrite to small beam current electron irradiation can only enhance its magnetic susceptibility from 4 to 5-fold. Enhancement of magnetic property by radiation induced defects and excitation in minerals is limited. Strong beam current electron irradiation provides a novel approach to enlarge the magnetic property differences between iron bearing minerals.

6

Determination of microamounts of sulfides and thiosulfates present together by means of induced iodine-azide reaction

Kurzawa J., Krzymińska A.

Chemia Analityczna

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2004

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Vol. 49, No. 4

569-576

EN

The induced iodine-azide reaction was applied to the titrimetric codetermination of microamounts of thiosulfates and sulfides. In one part of the sample the iodine consumed in the reaction induced by both inductors was determined. From the second sample one removed sulfides quantitatively by expelling H2S with N2 at pH 5. Alternative method of the removal of sulfides was based on their precipitation with zinc carbonate hydroxide suspension. After that the iodine consumed by the remaining thiosulfates was determined. From these two determinations the amount of both compounds was estimated. The method was applied to the determination of thiosulfates and sulfides in their mixtures and to the investigation of the stability of the prepared sulfide solutions and natural spring water containing sulfides. The proposed method allows one to determine both compounds at the concentration as low as 0.4 mmol L-1 with standard deviation š0.02.

PL

Opracowano metodę współ oznaczania siarczków i tiosiarczanów za pomocą indukowanej reakcji jodo-azydkowej. W jednej próbce oznaczono ilość jodu zużywanego w reakcji indukowanej łącznie przez oba związki. W drugiej próbce oznaczono ilość jodu zużywanego przez sam tiosiarczan po wcześniejszym ilościowym usunięciu siarczków przez wyparcie H(2)S za pomocą N(2), z roztworu o pH 5. Alternatywna metoda usunięcia siarczków polegała na ich wytrąceniu za pomocą zawiesiny węglanu sodu i octanu cynku. W oparciu o te dwa pomiary oznaczano ilość obu induktorów. Metodę zastosowano do oznaczania siarczków i tiosiarczanów w mieszaninie, badania trwałości rozcieńczonych roztworów siarczków oraz siarkowodorowych wód źródlanych. Metoda umożliwia oznaczanie obu związków począwszy od stężenia 0.4 mmol L(-1) z odchyleniem standardowym š0.02.

7

The influence of aliovalent impurities on transport properties of nonstoichiometric manganous sulphide

Mrowec S., Grzesik Z.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 1

37-49

EN

The influence of chromium and lithium on the manganese sulphidation kinetics has been studied as a function of temperature (973-1273 K) and sulphur activity (10(-1)-10(4)Pa) using a novel microthermogravimetric technique. It has been shown that the sulphidation of Mn-Cr and Mn-Li alloys, like that of pure manganese metal, follows strictly parabolic rate law being thus diffusion controlled. In agreement with the defect model of Mn(1-y)S it has been found that the sulphidation rate of Mn-Cr alloy is higher than that of pure manganese, the reaction rate is pressure independent and the activation energy of this process is lower. This implies that the concentration of cation vacancies in Mn(1-y)S-Cr(2)S(3) solid solution is fixed on the constant level by three-valent chromium ions substitutionally incorporated in the cation sublattice of this sulphide. In the case of Mn-Li alloy, on the other hand, the sulphidation rate is lower than that of pure manganese, and the activation energy is higher. These results can again be explained in terms of doping effect.

8

Dithiocarbonate and trithiocarbonate complexes derived from VV, MoVI, ReVII tetraoxothioprecursors

Dessapt R., Simonnet-Jegat C., Secheresse F.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 1

15-25

EN

Reactions of MoS(2)/(4), MoO(2)S(2)(2-), MoO(2)(4), ReSJ, ReO-(4), VS(3)/(4), and VO(3-)(4) with CS(2) are described. The syntheses and X-ray determinations of (NEt(4))(2) [Mo2(S)(2) (Mo(2) S)(2) (u -S)(2)], space group P2(1)/C, a = 9.3169(3) A,b = 16.3211(5) A, c = 22.8415(5) A, Beta = 92.590(1)°, V = 3469.8(2) A3, R = 0.0898 for 8720 independent reflections and (NEt(4))(2)[Mo(2)(O)(2)(Mi - S)(mi - O)(n(2) - COS(2)2] 0.5 CS(2), space group P2(1)/C, a = 9.8190(1) A, b = 20.6313(13) A, c = 15.7193(3) A, Beta = 92.353(1)°, V = 3181.71(8) A(3), R = 0.0576 for 5760 independent reflections are presented. A rationalization of the syntheses is discussed and the structure of (NH4)[HCOS(2) is described, space group Pca2i, a = 8.3174(9) A, b = 5.6562(6) A, c = 10.7125(12) A, V = 503.97(9) A3, R = 0.0402 for 952 independent reflections. (13)C NMR data for trithiocarbonate and dithiocarbonate complexes are presented.

9

Sulfide stress cracking of pipeline steels.

Krutsan A., Melekhov R., Tubielevich K.

Inżynieria Materiałowa

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2001

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R. XXII, nr 4

494-496

EN

The problem of the sulfide stress corrosion cracking of pipeline steels and their welded joints have been presented for pipeline steels. Results of hydrogen sulfide stress cracking inhibitors and corrosion inhibitors of three types protective actions on pipeline steels of two grades petroleum range of products are given.

10

Hydrogen effects in 34CrMo4 steel in H2S environment.

Kłyk K., Sozańska M., Galland J., Dagbert C., Sojka J.

Inżynieria Materiałowa

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2001

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R. XXII, nr 4

446-449

EN

34CrMo4 steel used for cylinders for technical gases storage can be used for gases containing hydrogen, since it meets the requirements of NACE Standard TM0177-90. Microscopic investigations showed that the steel structure is a martensitic one. An influence of the applied stress Rsk (time to failure t) on the fracture character was analysed by the quantitative fractography methods. The presence of hydrogen was disclosed in a form of numerous microcracks.

11

Wpływ dyspersyjnych wtrąceń niemetalicznych na rozrost ziarn austenitu w stalach mikrostopowych.

Garbarz B., Żak A., Wojtas J., Molenda R.

Inżynieria Materiałowa

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1999

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R. XX, nr 1

5-12

PL

Powstające w warunkach przyspieszonego krzepnięcia drobne cząstki wtrąceń tlenkowych i/lub siarczkowych mogą oddziaływać hamująco na rozrost ziarn. Potwierdzenie tego efektu umożliwiłoby wykorzystanie niepożądanych w stali wtrąceń niemetalicznych w celu poprawy jej własności mechanicznych. W artykule przedstawiono wyniki badań, których celem było ustalenie wpływu zwiększonych w porównaniu z technologią konwencjonalną COS szybkości krzepnięcia i chłodzenia po zakrzepnięciu na wielkość powstałych w takich warunkach cząstek siarczków oraz zbadanie oddziaływania tych cząstek na rozrost ziarn austenitu. Badania wykonano na wlewkach laboratoryjnych odlanych w warunkach symulujących ciągłe odlewanie wlewków cienkich grubości 50 mm. Wytopy doświadczalne zaprojektowano jako wytopy bezglinowej niskowęglowej stali mikrostopowej. Założono utrzymanie na stałym poziomie zawartości węgla, manganu, krzemu, wanadu i fosforu oraz na dwóch poziomach zawartości siarki i tytanu. Jako materiał porównawczy w badaniach rozrostu ziarn austenitu wykorzystano wlewki laboratoryjne ze stali mikrostopowych, które odlewane były w warunkach symulujących krzepniecie i chłodzenie po zakrzepnieciu konwencjonalnego ciągłego wlewka grubości 300 mm. Drobne wtrącenia niemetaliczne badano w prześwietleniowym mikroskopie elektonowym techniką cienkich folii, stosujac do określania ich składu chemicznego analizator LINK-ISIS ze spektrometrem EDS. W badanych próbkach stwierdzono występowanie dyspersyjnych wydzieleń siarczków manganu, siarczków miedzi oraz siarczków mieszanych Mn-Cu-S, z różnymi udziałami manganu i miedzi. Wielkość najmniejszych obserwowanych cząstek siarczków wynosiła ok. 30 nm, a średni rozmiar większości siarczków mieścił się w przedziale 50-100 nm. Problem wydzielania siarczków miedzi w stalach konstrukcyjnych, zwłaszcza w postaci dyspersyjnej nie został jak dotąd szczegółowo zbadany, a wyniki badań z tego zakresu można znaleźć jedynie w kilku publikacjach. Badania rozrostu ziarn austenitu potwierdziły występowanie efektu zakotwiczenia granic ziarn przez dyspersyjne cząstki siarczków. W badanych wlewkach cienkich nie stwierdzono anormalnego rozrostu ziarn, który jest typowy dla wlewków o większych przekrojach ze stali mikrostopowych zawierajacych czastki kotwiczące granice ziarn.

EN

Fine particles of oxide and/or sulphide inclusions can hinder the grain growth. Confirmation of that effect could enable to use unwanted nonmetallic inclusions for improvement of steel properties. In this paper the effect of the increased - in comparison with conventional continuous casting - cooling rates on the size of sulphide particles and the results of investigation of influence of the sulphide particles on the austenite grain growth has been presented. It the investigation experimental ingots cast under conditions simulating continuous casting of a thin slabs 50 mm in thickness were used. Experimental ingots were cast as aluminium free microalloyed steels with specified at the same levels of C, Mn, Si, V and P and with content of S and Ti. In the grain growth studies, samples of reference ingots cast under conditions simulating conventional continuous casting of a 300 mm thick slab were used for comparison purposes. Fine nonmetallic inclusions were investigated in the transmission electron microscope using thin foil technique and chemical composition of the particles was established using LINK-ISIS system equipped with EDS spectrometer. In the investigated specimens of the thin ingots fine particles of manganese sulphides, copper sulphides, and mixed Mn-Cu-S sulphides with varying content of Mn and Cu were found. The size of the finest sulphides was about 30 nm and average size of majority of the sulphides was found to be in the range of 50-100 nm. The problem of copper sulphides precipitation in structural steels has not been yet investigated in detail and only few papers dealing with it could be found. As the result of grain growth characteristics investigation the effect of pinning of the grain boundaries with fine particles of sulphides was found. In the investigated thin ingots no abnormal grain growth typical for continuously cast microalloyed steels ingots of conventional dimensions took place.

12

Termodynamiczne i kinetyczne uwarunkowania reakcji chemicznych na powierzchni żelaza i chromu w atmosferze SO2 w wysokiej temperaturze.

Gilewicz-Wolter J., Żurek Z., Środa S.

Inżynieria Materiałowa

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1999

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R. XX, nr 5

558-561

PL

W pracy przedyskutowano termodynamiczne i kinetyczne uwarunkowania tworzenia się zgorzelin tlenkowo-siarczkowych na żelazie i chromie w atmosferze SO2. Proces korozji żelaza i chromu jest bardzo złożony i można go wyjaśnić tylko w oparciu o przesłanki kinetyczne jak i termodynamiczne. Transport reagentów przez rosnącą zgorzelinę jest czynnikiem decydującym o przebiegu procesu korozji i budowie morfologicznej zgorzeliny.

EN

The oxidation of Fe and Cr in SO2 has been studied at 1073K-1273K at 100K intervals. The corrosion kinetics follows the parabolic rate law to a good approximation for iron. Only small deviation from parabolic rate law in initially stage process was observed, whereas oxidation process of chromium proceeds according linear rate law at 10 to the 5 Pa of SO2, parabolic rate law at 1173K and 1273 at 3*10 to the 4 Pa of SO2. The transport phenomena by radiotracer techniques were studied. The scales were composed of sulphide and oxide and grew by the outward diffusion of metals. Inward transport of SO2 molecules through the discontinuities in the scale was observed. The mechanism of sulphide and oxide formation was discussed on the basis of the thermodynamics and kinetics predictions.

13

Ocena poziomu zanieczyszczenia metalami ciężkimi i anionami nieorganicznymi gleby, wody i warzyw ogródków działkowych Zdzieszowic

Wacławek W., Kwak A., Bołym M., Mołko A.

Chemia i Inżynieria Ekologiczna

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1998

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Vol. 5, nr 8-9

767-777

PL

W pracy przedstawiono wyniki badań dotyczących oceny poziomu zanieczyszczenia gleb, wód gruntowych oraz warzyw dwóch kompleksów działkowych Zdzieszowic. Do badanych zanieczyszczeń należały: jony nieorganiczne (azotany (III) i (V), chlorki oraz siarczany), jak również metale ciężkie (Zn, Cu, Pb, Cd). Próby do badań pobierano w całym okresie wegetacyjnym. Oznaczanie ww. analitów wykonano, stosując metody spektrofotometryczne [wzory], potencjometryczne [wzór] i absorpcyjnej spektrometrii atomowej (metale ciężkie). Otrzymane wyniki porównano z obowiązującymi normami, które w większości wypadków były dotrzymane.

EN

Results of assesment of contamination level of soil, groundwater and vegetables of two allotments have been presented. The following contaminants were analyzed: nitrates (III) and (V), chloride, sulfide and heavy metals. Samples were taken in all plant growth period. The following analytical methods were used: spectrophotometric metod, weight method [formula], potentiometric method [formula], atomic absorption spectroscopy method (heavy metals). The results obtained have been compared with legal standards.