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1

Using an Interdigital Micromixer for Separation of In3+ from Zinc Hydrometallurgical Process with D2EHPA as an Extractant

Li C., Jiang F., Ju S., Peng J., Wei Y., Zhang L.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2A

873--878

EN

Experiments were performed in an interdigital micromixer with 30 microchannels (40 μm width of each channel) to separate In3+, Fe3+ and Zn2+ from sulfate solutions using Di-(2-ethylhexyl)phosphoric acid (D2EHPA) as the extractant. The effects of pH, extractant concentration and flow rate on the extraction efficiency and flow rate on mass transfer coefficient of In3+, Fe3+ and Zn2+ were investigated. At a phase flow rate of 7.0 mL/min and initial solution pH of 0.423, the extraction efficiency of In3+, Fe3+ and Zn2+ was 99.29%, 3.43% and 2.54%, respectively and mass transfer coefficient of In3+, Fe3+ and Zn2+ was 144.307 s-1,1.018 s-1 and 0.750 s-1. Then, the loaded organic phase was stripped in an interdigital micromixer. At a phase flow rate of 9.0 mL/min and HCl concentration of 160 g/L, stripping efficiency of In3+ was 98.92% and mass transfer coefficient of In3+ was 169.808 s-1, while concentration of Fe3+ and Zn2+ was lower than 0.005 g/L with good separation of In3+ from Fe3+ and Zn2+.

2

Zastosowanie pogłębionego utleniania odczynnikiem Fentona w połączeniu ze strippingiem powietrzem do oczyszczania ścieków pochodzących z procesu zgazowania biomasy

Gościniak Ł.

Chemik

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2016

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Vol. 70, nr 4

209--218

PL

Frakcja wodna, powstająca w instalacjach zgazowania stanowi złożoną mieszaninę zawierającą w swym składzie zarówno zanieczyszczenia fizyczne, jak i szereg substancji o różnej budowie chemicznej; jest uciążliwym produktem ubocznym procesu termicznego przetwórstwa biomasy. W pracy dokonano oceny możliwości zastosowania strippingu powietrzem do usuwania zanieczyszczeń z frakcji ściekowych oraz jego wpływu na skuteczność procesów pogłębionego utleniania przy zastosowaniu nadtlenku wodoru lub odczynnika Fentona.

EN

The water fraction coming from the gasification installations, due to being a complex mixture of physical pollutions and various chemicals, remains as a burdensome by-product of the process of the biomass thermal processing. As a part of this paper, the evaluation of the possibilities of using air stripping in order to remove the pollution from the tar water fraction, as well as, its influence on the processes of advanced oxidation with the Fenton’s reagent or with hydrogen peroxide has been made.

3

Studies on Cementation of Tin on Copper and Tin Stripping from Copper Substrate

Rudnik E., Sikora P.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 2A

593--598

EN

Cementation of tin on copper in acid chloride-thiourea solutions leads to the formation of porous layers with a thickness dependent on the immersion time. The process occurs via Sn(II)-Cu(I) mechanism. Chemical stripping of tin was carried out in alkaline and acid solutions in the presence of oxidizing agents. It resulted in the dissolution of metallic tin, but refractory Cu3Sn phase remained on the copper surface. Electrochemical tin stripping allows complete tin removal from the copper substrate, but porosity and complex phase composition of the tin coating do not allow monitoring the process in unambiguous way.

4

Determination of formation constants of uranyl(VI) complexes with a hydrophilic SO3-Ph-BTP ligand, using liquid-liquid extraction

Steczek L., Narbutt J., Charbonnel M. -C., Moisy P.

Nukleonika

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2015

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Vol. 60, No. 4, part 2

821--827

EN

Complex formation between uranyl ion, UO2 2+, and a hydrophilic anionic form of SO3-Ph-BTP4– ligand, L4–, in water was studied by liquid-liquid extraction experiments performed over a range of the ligand and HNO3 concentrations in the aqueous phase, at a constant concentration of nitrate anions at 25°C . The competition for UO2 2+ ions between the lipophilic TODGA extractant and the hydrophilic L4– ligand leads to the decrease in the uranyl distribution ratios, D, with an increasing L4– concentration. The model of the solvent extraction process used accounts – apart from uranyl complexation by TODGA and SO3-Ph-BTP4– – also for uranyl complexation by nitrates and for the decrease in the concentration of the free L4– ligand in the aqueous phase, due to its protonation, bonding in the uranyl complex and the distribution between the two liquid phases. The unusually strong dependence of the D values on the acidity, found in the experiment, could hardly be explained as due to L4– protonation merely. Three hypotheses were experimentally tested, striving to interpret the data in terms of additional extraction to the organic phase of ion associates of protonated TODGA cation with either partly protonated anionic L4– ligands or anionic UO2 2+ complexes with NO3 – or L4–. None of them has been confi rmed. The analysis of the results, based on the formal correction of free ligand concentrations, points to the formation of 1 : 1 and 1 : 2 uranyl – SO3-Ph-BTP complexes in the aqueous phase. The conditional formation constant of the 1:1 complex has been determined, logβL,1 = 2.95 ± 0.15.

5

The effects of the coating stripping process on regenerated tool cutting edges

Toboła D., Czechowski K., Wrońska I., Łętocha A., Miller T.

Journal of Achievements in Materials and Manufacturing Engineering

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2013

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Vol. 61, nr 2

294--301

EN

Purpose: The cutting tools of high speed steel or cemented carbide need to be regenerated in many cases. This involves stripping the remnants of the initial coatings. The effects of chemical removal of the PVD TiN, TiAlN, TiN/(TiAlSi)N/TiN and TiZrN/10x(TiN/ZrN)/TiN coatings on some elements of geometry of cutting edges and the adhesion of subsequent coatings deposited on the cutting inserts are considered. Design/methodology/approach: Scanning electron microscopy is used to examine the structures after the various stages of inserts regeneration: with the initial coating, after it is chemically stripped and subsequently deposited. Geometry of cutting edges, i.e. roughness, edge roundness radius and 2D and 3D geometric structure of rake and flank faces, as well as the adhesion of subsequent coatings deposited on the inserts in the regeneration process are determined. Findings: The chemical coating stripping process did not cause unfavourable changes in the roughness parameter Ra of the rake and flank faces of cutting inserts, or in the roughness of their cutting edges. Subsequent coatings deposited on the decoated inserts had a marginally lower adhesion, but in the case of TiN coated cemented carbide, the latter coating had better adhesion than the original. Surface analyses showed that the PVD coating stripping methods were effective for TiN and TiAlN coated high speed steel HS6-5-2 inserts, as well as for TiN coated and commercially TiN/(TiAlSi)N/TiN coated cemented carbide inserts. Research limitations/implications: The paper is concerned with geometry of cutting edge and adhesive properties of subsequent coatings. To verify fully the effectiveness of the methods described further research on different coating removal from tools made of various tool materials should be carried out. Practical implications: The methods and chemicals used for removal of the initial PVD TiN, TiAlN and TiN/(TiAlSiN)/TiN coatings from high speed steel and cemented carbide inserts proved effective and may be used in the regeneration process of cutting tools. Originality/value: The effects of chemical removal of mono and multilayer PVD coatings from cemented carbide and high speed steel inserts on the regenerated cutting edges quality have been determined.

6

Recovery of HCL from chloride leach solution of spent HDS catalyst by solvent extraction

Banda R., Nguyen T.H., Lee M.S.

Chemical and Process Engineering

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2013

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Vol. 34, nr 1

153--163

EN

In the present work, amine based extractant and its mixture with cationic and solvating extractants were tested for the extraction of HCl from chloride solution containing Al(III). The chloride feed solution resulted from the leaching of spent HDS (hydro-desulfurization) catalysts. For this purpose, amine extractants, such as TOA (trioctyl amine), Alamine 336 (a mixture of tri-octyl/decyl amine), Alamine 308 (tri-isooctyl amine), and TEHA (tri 2-ethylhexyl amine) were used and the extraction and stripping behavior of HCl was compared. The extracted HCl was easily stripped from loaded TEHA phase, when compared with the other tested tertiary amine system. Solvent extraction reaction of HCl by TEHA was determined from the extraction data. Unlike TOA and Alamine 336, adding cationic extractant to TEHA had negligible effect on the extraction and stripping of HCl. In our experimental ranges, no Al was extracted by amines and pure HCl was recovered. MaCabe-Thiele diagrams for the extraction and stripping of HCl by TEHA were constructed.

7

Removal of phenols from aqueous solutions with solvating extractants

Regel-Rosocka M., Wiśniewski M.

Polish Journal of Chemical Technology

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2010

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Vol. 12, nr 3

19-23

EN

The removal of selected phenols (phenol, 4-methoxyphenol, 4-fluorophenol, 4-nitrophenol, 4-methylphenol, 4-chlorophenol, 2,4-dichlorophenol) from aqueous streams by liquid-liquid extraction is studied. Butylene and propylene carbonate – are used as green extractants. They permit to remove almost 100% of the examined phenols from feed solutions of phenol concentration about 20 g/dm3. Additionally, stripping of phenols from loaded organic phases is carried out with NaOH. The results of extraction parameters for alkylene carbonates (extraction efficency and distribution ratio) are compared with commercial solvating extractant – Cyanex 923.

8

Usuwanie związków chloroorganicznych ze ścieków przemysłowych ze szczególnym uwzględnieniem metody termokatalitycznego utleniania

Żarczyński A., Stopczyk A., Zaborowski M., Gorzka Z., Kaźmierczak M.

Ochrona Środowiska

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2010

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Vol. 32, nr 1

49-54

PL

Scharakteryzowano wybrane metody wydzielania zanieczyszczeń chloro-organicznych ze ścieków, takie jak desorpcja gazem obojętnym lub parą wodną, ekstrakcja rozpuszczalnikami, adsorpcja na węglu aktywnym czy wymiana jonowa. Mogą być one etapem wstępnym do odzysku, albo przy braku jego opłacalności, do termokatalitycznego lub termicznego utleniania tych zatężonych już zanieczyszczeń. Przedmiotem badań katalitycznego utleniania organicznych związków chloru były m.in. tetrachlorometan, 1,1,1-trichloroetan, 1,1,2,2-tetrachloroetan i chlorohydryna propylenowa. W badaniach zastosowano katalizatory ziarniste - platynowy i palladowy, a także katalizator monolityczny - platynowo-rodowy. Wykazano, że utlenienie badanych chloropochodnych zachodziło całkowicie z udziałem katalizatorów w temperaturze 325÷550 stopni C, przy czym łatwiej utleniały się z ich udziałem związki tlenowe niż bez tlenowe, zaś najtrudniej TChE. Katalizatory ziarniste (KP-910 i Pd) okazały się aktywniejsze od katalizatora monolitycznego (Pt-Rh), przy czym nie stwierdzono dezaktywacji katalizatorów. Zastosowanie katalizatorów pozwoliło na utrzymanie zawartości PCDD/Fs w gazach odlotowych znacznie poniżej wartości dopuszczalnej w krajach Unii Europejskiej (0,1ngTEQ/m3). Dane literaturowe oraz wyniki badań własnych świadczą o możliwości prawie trzykrotnego obniżenia temperatury unieszkodliwiania odpadowych organicznych związków chloru w procesie katalitycznym, w porównaniu do obecnie stosowanego spalania wysokotemperaturowego (1300÷1350 stopni C).

EN

A characteristics is given of the following methods for the separation of chloroorganic pollutants from wastewater: desorption with inert gas or water vapour, extraction with solvents, adsorption onto active carbon, and ion exchange. The processes can be used as prior steps either to the recovery of valuable substances or, if their recovery is not cost-effective, to the thermocatalytic or thermal oxidation of the pollutants already concentrated. The organic chlorine compounds chosen for the thermo-catalytic oxidation investigated within the scope of the present study included tetrachloromethane, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane and propylene chlorohydrin. Experiments were carried out using platinum- or palladium-based granular catalysts, as well as a monolithic platinum-rhodium catalyst. The findings of the study can be itemized as follows: (1) In the presence of the catalysts tested, complete oxidation was achieved over the temperature range of 325-550 oC; (2) oxygen compounds were easier oxidable than non-oxygen compounds, and TChE displayed the lowest oxidability; (3) the activity of the granular catalysts (KP-910 and Pd) was higher than that of the monolithic (Pt-Rd) catalyst, and (4) none of the catalysts tested was deactivated. The application of the catalysts enabled the PCDD/Fs content of the reaction gases to be maintained below the admissible value established for the EU Member States (0.1 ngTEQ/m3). The data reported in the literature, as well as the authors' own results, indicate that the temperature at which the chloroorganic wastes undergo catalytic oxidation can be reduced nearly threefold as compared to the temperature presently applied (1300 to 1350 oC).

9

Water and frost resistance of gap - graded asphalt modified with the SBS polymer and hydrated lime

Iwański M., Pobocha M.

Foundations of Civil and Environmental Engineering

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2008

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No. 11

29-36

EN

Gap - graded asphalt (MNU) has high resistance to the traffic, however, due to its specific grading it is more prone to a destructive effect of the climatic factors compared to other bituminous mixes. In order to ensure its durability, the mixture was modified with the use of the SBS polymer and hydrated lime. Asphalt was modified with the addition of 2, 4, 6, 8 % of the SBS polymer, while hydrated lime was dispensed in the filler in the amounts 10, 20, 30, 40 and 50 %. The performed research into the resistance of MNU to high and low temperatures as well as to water and frost showed a positive impact of the two modifiers on the durability and high mechanical properties of MNU.

10

The effectiveness of hydrated lime as asphalt concrete additive

Jaskuła P.

Foundations of Civil and Environmental Engineering

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2007

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No. 10

99-109

EN

This paper evaluates the effectiveness of hydrated lime as an additive to asphalt concrete based on laboratory, as well as field tests carried out on the rest section. The research included testing of the resistance to the action of water and frost and to permanent deformation, as well as establishing of pavement condition survey parameters, including transverse profile and skid resistance on the test section constructed with asphalt mixtures containing hydrated lime or liquid antistripping additive. It was established that hydrated lime may be added to asphalt concrete mixtures as an alternative to chemical antistripping additives.

11

SEM and profilometric evaluation of enamel surface after air rotor stripping – an in vitro study

Mikulewicz M., Szymkowski J., Matthews-Brzozowska T.

Acta of Bioengineering and Biomechanics

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2007

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Vol. 9, nr 1

11-17

EN

The aim of the study was to evaluate roughness of the enamel surface after Air Rotor Stripping (ARS). Thirty interproximal surfaces of human premolars were used as the biological material. Research was conducted using a contact profilometer and a scanning electron microscope (SEM). Sets of 3D parameters and topographical maps of enamel surface before and after ARS treatment were used to define roughness of the surfaces. SEM images of stripped surfaces were taken with microscopic magnification of 100× and 1000×. The data revealed a general roughness of enamel arising after ARS procedure. Summarized values of chosen parameters increased after ARS procedure compared to the values of untreated enamel. Topographical maps showed areas of both well polished and badly polished enamel. In conclusion, comparison of the mean values of the measured parameters of ARS treated enamel surfaces indicated that roughness of the enamel arises after ARS, but it must be emphasized that on every evaluated surface well polished areas were also present. Moreover, the well polished areas were smoother than those on the untreated enamel surfaces. Contact fluoridation and improved oral hygiene after ARS appear to be necessary because of the presence of areas of increased roughness on evaluated surfaces.

12

Odpady wydobywcze - przewidywane zmiany prawne

Dulewski J., Madej B.

WUG : bezpieczeństwo pracy i ochrona środowiska w górnictwie

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2006

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nr 6

5-8

PL

W artykule zwrócono uwagę na specyfikę rozwiązań prawnych odnoszących się do gospodarowania odpadami wydobywczymi. Omówiono główne założenia dyrektywy w sprawie gospodarowania odpadami z przemysłu wydobywczego. Przedstawiono również zmiany w ustawie o odpadach oraz wynikające z nich konsekwencje dla sektora górniczego. Dla zobrazowania skali problemu zaprezentowano dane liczbowe charakteryzujące gospodarkę odpadami wydobywczymi w Polsce.

EN

This article presents the specificity of the legal solutions in relation o the management of mining waste. Authors describe the most essential stipulations of Directive on the management of waste from the extractive industries. The article includes information about legal changes in the Polish waste legal system as well as problems faced by the mining sector. Presented has been the actual data characterizing the management of mining waste in Poland.

13

Extractive removal of arsenic from sulphuric acid solutions

Wiśniewski M., Iberhan L.

Polish Journal of Chemical Technology

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2004

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Vol. 6, nr 3

41-44

EN

In the study, the extraction of arsenic(III) and arsenic(V) was investigated from the concentrated aqueous solutions of the sulphuric acid using the hydrophobic reagents of various structure and composition. The studies included stripping with water, too. The studies took advantage of the organophosphorus extracting agents CyanexŽ 923, CyanexŽ 925, CyanexŽ 301 and their mixtures, as well as of the 2-ethylhexane-l,3-diol and the hydroxamic acids dissolved in toluene. The study aimed at the removal of the maximum amounts of arsenic(III) and arsenic(V) from the sulphuric acid solution at the concentration of 150 g/dm3, using the multistage co-current or the counter-current extraction and, then, the removal of the arsenic from the organic phases by stripping with the water, with the regeneration of the extracting agent. The linear extraction and the stripping isotherms obtained in a given range of the concentrations, were used for a discussion on the multistage extraction, and the stripping of arsenic. The experimental results proved to be consistent with the obtained isotherms of the two processes and their equations.

14

Microstructural and topographical evaluation of human enamel

Matthews-Brzozowska T., Mikulewicz M., Szymkowski J.

Elektronika : konstrukcje, technologie, zastosowania

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2004

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Vol. 45, nr 8-9

106-108

EN

Evaluation of human enamel in "in vitro" conditions can be conducted by microscopic and profilometric techniques which can describe delivered surface in quantitative and qualitative way. The aim of the research was to evaluate surface roughness of human enamel alter reduction of enamel (stripping). Research delivered information about enamel condition and allowed for comparison between SEM images and 30/2D parameters.

PL

Ocena ludzkiego szkliwa w warunkach in vitro może być prowadzona z użyciem technik mikroskopowych lub profilometrycznych. Celem przedstawionych badań było dokonanie oceny chropowatości powierzchni szkliwa nazębnego po operacji wygładzania. Badania dostarczyły informacji o stanie powierzchni szkliwa i umożliwiły porównanie obrazów z mikroskopu skaningowego z 3D/2D parametrami.

15

Odzyskiwanie chloropochodnych organicznych ze ścieków w układzie stripper-adsorber

Myszkowski J., Milchert E.

Przemysł Chemiczny

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2003

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T. 82, nr 8-9

1048-1050

16

Recovery of zinc(II) from model hydrochloric acid solutions in hollow fiber modules

Tórz M., Alejski K., Szymanowski J.

Physicochemical Problems of Mineral Processing

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2002

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Vol. 36

101-113

EN

The recovery of zinc(II) from model hydrochloric acid solutions in hollow fiber modules was studied. It was found that zinc(II) could be removed from these model solutions by 80% tributyl phosphate in kerosene. The efficiency of extraction was limited by low values of zinc(II) distribution coefficients. Two types of experiments were carried out: the extraction in one module and the extraction-stripping process in a set of two modules. Simplified models of mass transfer based on the solute concentration changes in the aqueous phases were formulated and verified.

PL

W pracy przedstawiono wyniki badań ekstrakcji i reekstrakcji jonów cynku(II) w modułach z włóknami kapilarnymi z modelowych roztworów kwasu solnego o składzie zbliżonym do roztworów potrawiennych pochodzących z ocynkowni stosujących metodę cynkowania ogniowego. Stosowanym ekstrahentem był fosforan tributylu, fazą odbierającą natomiast woda. Wykazano, że cynk(II) może być usuwany z roztworów modelowych w modułach z włóknami wydrążonymi, przy czym o wydajności procesu decydował niski współczynnik podziału cynku(II) między fazę organiczną i wodną. Sformułowano oraz pozytywnie zweryfikowano uproszczony model matematyczny procesu, bazujący na bilansie masowym jonów cynku w fazach wodnych.

17

Extraction of Ir(III) with Cyanex-923 and Cyanex-471X from bromide media and its separation from Pt(IV), Pd(II) and Rh(III)

Duche N. S., Dhadke M. P.

Polish Journal of Chemical Technology

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2001

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Vol. 3, nr 1

21-25

EN

Iridium(III) was extracted with Cyanex-923 and Cyanex-471X in toluene from bromide media and studied. The quantitative extraction was observed in the range of 5.0 - 6.0 M HBr with 1.0M Cyanex-923 and at 1.3 M Cyanex-471X in toluene, while metal ion was stripped out from organic phase of Cyanex-923 and Cyanex-471X with the mixture of 4.0 M HC1O4 + 2.0 M HNO3 and 6.0 M H2SO4 + 4.0 M HC1 respectively. In both the cases extraction of Ir(III) decreased with the increased concentration of stannous chloride. The thermal study showed that the extraction reactions are exothermic in nature with both the reagents, and the stoichiometric ratio of Ir(III) to Cyanex-923/Cyanex-471X in organic phase was 1:3. The separation of Ir(III) from Pt(IV), Pd(II), and Rh(III) has been also studied.