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1

Use of manganese sulfide as a sustainable precipitant for the separation of Co(II) and Ni(II) by sulfide precipitation from spent lithium-ion battery leachates

Ho Huu Loi, Lee Man Seung

Physicochemical Problems of Mineral Processing

|

2025

|

Vol. 61, iss. 5

art. no. 213561

EN

The rising uptake for lithium-ion batteries (LIBs) requires the need for effective recycling methods to recycle critical metals like cobalt, nickel, and manganese while minimizing environmental harm. In general, hydrometallurgical treatments of spent LIBs result in leachates that contain Co(II), Mn(II) and Ni(II) with diverse concentration ratio. By utilizing the difference in the solubility products among CoS, NiS and MnS, it is possible to simultaneously precipitate CoS and NiS, leaving Mn(II) in the filtrate. This study employed MnS as a cost-effective and eco-friendly precipitant for selective precipitation of Co(II) and Ni(II) sulfide from simulated solution containing Mn(II). Among several factors, the influence of solution pH, MnS dosage and reaction time was found critical on the precipitation of Co(II) and Ni(II) at room temperature. Under optimized conditions: pH 2.0, a MnS/(Co + Ni) molar ratio of 10, agitation speed of 400 rpm at 25℃, use of MnS led to complete precipitation of CoS and NiS, leaving Mn(II) in the filtrate with minimal contamination. Moreover, common ion effect and encapsulation effect were observed to affect the dissolution behavior of MnS during the precipitation. Unlike traditional sulfide sources like Na₂S and NaHS, MnS provides a controlled release of sulfide ions, addressing challenges like the formation of colloidal particle. Our results indicated that MnS demonstrated its potential as a precipitant for the selective precipitation of Co(II) and Ni(II) from the acidic media containing Mn(II).

2

Deposit potential and distribution of cobalt and nickel in the sludge of chromite placer mining process at Nui Nua ultramafic massif area, Thanh Hoa province, Vietnam

Ban To Xuan, Giang Nguyen Khac, Duc Tran Van, Dung Le Tien

Geology, Geophysics and Environment

|

2024

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Vol. 50, no. 4

383--400

EN

Chromite placer is widely distributed in Quaternary sediments located around the Nui Nua ultramafic massif in Thanh Hoa province, Vietnam. The long-term mining works targeting chromite placer in this area have left a huge amount of waste sludge, up to tens of millions of tons. The paper aims to introduce a deposit potential and distribution of cobalt- and nickel- bearing minerals within the waste sludges generated from the chromite placer mining operations around the mines situated near the Nui Nua ultramafic massif in Thanh Hoa province, Vietnam. Based on field investigations and sample analyses, two groups of waste sludge have been identified: clay-sized sludges and debris waste sludges. The former group is plastic bentonite clay, distributed in depressions and low terrain, and has low contents of cobalt (0.06%) and nickel (0.67%), which is of impractical significance for the recovery purposes of cobalt and nickel. The latter group is usually distributed in relatively high terrain, forming waste sludge ranging from several thousand to hundreds of thousands of tons in volume. These deposits include rock fragments, mineral fragments derived from the Nui Nua ultramafic massif, along with dark spherical nodules rich in goethite, limonite, and Fe-Mn hydroxides, which contain relatively high contents of cobalt (up to 0.75%) and nickel (up to 2.43%) in the waste sludge and chromite placer mines. The cobalt and nickel are mainly concentrated in Fe-Mn nodules made up of goethite, limonite, todorokite, and other Fe-Mn hydroxides. Data from chromite placer explorations, combined with the study results, provide reliable insights into the distribution of cobalt and nickel resources within the waste sludges and chromite placer deposits in the Co Dinh area (northeast of Nui Nua ultramafic massif) and Mau Lam (southwest of Nui Nua massif), Thanh Hoa province. A preliminary estimation of potential resources of Co and Ni metals have been made for the debris waste sludges at Co Dinh and Mau Lam areas based on the ratios of debris particles in the sludges and their contents of Co and Ni along with published resources and reserves of chromite placer ores.

3

Odzysk kobaltu i manganu ze strumieni odpadowych przemysłu petrochemicznego na przykładzie procesu produkcji kwasu tereftalowego

Kura Łukasz, Jurczakowski Rafał, Wiśniewski Piotr

Przemysł Chemiczny

|

2023

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T. 102, nr 6

600--605

PL

Stwierdzono ilościowe wytrącanie szczawianów kobaltu(II) i manganu(II) (stężenia metali poniżej LOD: Co < 0,35 ppm, Mn < 0,27 ppm) w stężonym roztworze kwasu octowego (90% mas.), powszechnie stosowanym jako rozpuszczalnik w przemysłowych procesach utleniania p-ksylenu do kwasu tereftalowego. Obecność zanieczyszczeń typowych dla procesu utleniania p-ksylenu, czyli kwasu benzoesowego, kwasu bromowodorowego oraz jonów sodu nie miała negatywnego wpływu na powstawanie osadów. Obecność stałego kwasu tereftalowego w mieszaninie reakcyjnej miała pozytywny wpływ na proces odzyskiwania katalizatora. Zaobserwowano, że szczawiany tworzą aglomeraty na powierzchni stałego kwasu tereftalowego, co ułatwia oddzielenie osadu od cieczy macierzystej. Ponadto potwierdzono wysoką efektywność wytrącania w szerokim zakresie stężeń metali (50-1600 ppm). Wyniki pokazują, że strącanie kwasem szczawiowym jest skuteczną metodą odzyskiwania katalizatorów homogenicznych zawierających związki kobaltu(II) i manganu(II).

EN

A 1% soln. of (COOH)₂ in 90% MeCOOH was added to a 90% MeCOOH soln. contg. Co and Mn ions at concns. of 500 and 300 ppm, resp., and impurities typical of the oxidn. of p-xylene to C₆H₄(COOH)₂ (BzOH, HBr and Na ions) in amts. simulating the mother liquor compn. of a real industrial process. After mixing, the Co and Mn contents of the decanted liq. were detd. by AAS. Presence of impurities had no neg. impact on the ppt. formation. The presence of solid C₆H₄(COOH)₂ in the reaction mixt. had a pos. impact on the catalyst recovery process. Oxalates formed agglomerates on the surface of the solid C₆H₄(COOH)₂ which facilitated the sepn. of the ppt. from the mother liquor. The pptn. with (COOH)₂ is an efficient recovery method of spend Co(II) and Mn(II) homogeneous catalysts.

4

Kinetic of Oil Sludge Thermolysis Process in Presence of Nickel, Cobalt and Iron-Supported Microsilicate

Tyanakh Sairagul, Baikenov Murzabek, Yun Ma Feng, Khamitova Tolkyn, Balpanova Nazerke, Tulebayeva Balzhan, Kyzkenova Aikorkem, Karimova Aliya, Rakhimzhanova N.Z., Kochegina E.V.

Polish Journal of Chemical Technology

|

2023

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Vol. 25, nr 3

101--109

EN

The article is devoted to the experimental determination of thermokinetic parameters of oil sludge thermal degradation using the model-free Ozawa-Flynn-Wall method in the presence of a nanocatalyst (nickel, cobalt and iron-supported microsilicate) by calculating Arrhenius kinetic parameters (activation energy and pre-exponential factor). The phase composition of the reflex microsilicate was established – 4.12; 2.51 Å – SiO2, nickel-supported microsilicate reflexes: 2.09; 1.48 Å – NiO, reflexes: 4.25 Å – SiO2 and acid numbers of microsilicate – 64 μmol/g of prepared nanocatalysts. Using the method of Brunauer, Emmett and Teller, the specific surface area of the microsilicate was established – 18.3 ± 0.3 m2 /g, the microsilicate with nickel applied – 20.9 ± 0.2 m2 /g and the adsorption isotherm of the prepared nanocatalysts (microsilicate with nickel, cobalt and iron). Thermokinetic parameters of thermal decomposition of oil sludge without a catalyst and with a catalyst at an increment of 0.9 are 99.0 and 93.3 kJ/mol nickel-supported microsilicate, 51.9 kJ/mol cobalt-supported microsilicate, 111.3 kJ/mol iron-supported microsilicate and non-metal-supported microsilicate 173.7 kJ/mol, respectively. The study of the kinetic parameters of pyrolysis of oil sludge using various catalysts makes it possible to assess their influence on the process of decomposition of organic components. The results of the experiments showed that the use of catalysts significantly affects the destruction of oil sludge. Dynamic thermal analysis at different heating rates studied the dynamics of oil sludge decomposition. The study of the effect of catalysts on the kinetic parameters of oil sludge pyrolysis is an important step in the development of new methods for the disposal of petroleum products and the reduction of their negative impact on the environment. The obtained experimental data on thermal degradation kinetics of oil sludge will find application in designing a reactor for the process of destructive hydrogenation of heavy hydrocarbon raw materials.

5

Mineralogy and in situ S and Pb isotope characteristics of ore minerals from polymetallic mineralization in the Gierczyn-Przecznica area, SW Poland

Foltyn Krzysztof, Kozub-Budzyń Gabriela Anna, Lahaye Yann, Piestrzyński Adam, Skirak Paulina, Zygo Władysław, Pieczonka Jadwiga

Geological Quarterly

|

2023

|

Vol. 67, No. 1

art. no. 10

EN

Chlorite-mica-quartz schist in the Gierczyn-Przecznica area in SW Poland contains polymetallic ores which were the source of tin and cobalt in the past. This mineralogical study revealed the presence of silver-bearing minerals including members of the tetrahedrite (Ag <3 apfu) and freibergite series (3 < Ag < 8 apfu), galena (0.26–1.48 wt.% Ag), and a phase with the chemical composition of Te-rich canfieldite Ag8Sn(S,Te)6. In Przecznica Sn-sulphides are represented by stannite while cobaltite is the most abundant host for cobalt, followed by Co-bearing arsenopyrite. Glaucodot, ullmannite and members of the löllingite-rammelsbergite solid-solution series (Fe,Ni,Co)As2 also contain cobalt but are scarce in the samples. An exposure in the “Psi Grzbiet” area is characterized by the presence of Ag, Ni, Sb and Te minerals accompanied by very small amounts of As-bearing phases (represented by arsenopyrite) while the mineralogical composition in the Przecznica area is characterized by an abundance of As phases and a lack of Sb minerals. Sulphur isotopes of sulphides from Przecznica are heavier than in most deposits related to the Karkonosze Granite intrusion, while their Pb isotope signature in galena suggests an Early Paleozoic pre-Variscan affinity rather than a Variscan one.

6

The influence of selected transition elements on cell metabolism

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

Ecological Chemistry and Engineering. S

|

2023

|

Vol. 30, nr 4

471--488

EN

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

7

Comparative performance assessment of nano-composite cathode of lmso-bscmf for low temperature solid oxide fuel cell applications

Subhashini P.V.C.K., Rajesh K.V.D.

Composites Theory and Practice

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2023

|

R. 23, nr 4

235--238

EN

The development of novel cathode materials for low temperature solid oxide fuel cell (SOFC) applications is one of the significant research areas in materials engineering. In the current work, composite cathode materials were prepared by two different modes and the fuel cell performance was assessed using a gadolinium-doped ceria (GDC) electrolyte. Nanocomposite cathodes were fabricated using a lanthanum strontium manganite oxide (LSMO) powder of a 50-100 nm particle size and Ba0.5Sr0.5(Co0.2Mg0.8)0.2Fe0.8O3 (BSCMF) powder of a 1 μm particle size. The cathodes were prepared as layered composites and mixed composites. The electrochemical performance of the symmetric cells was investigated by electrochemical impedance spectroscopy (EIS) at the intermediate temperature of 700°C using air atmosphere. The cathode film coating on the electrolyte was sintered at three different temperatures (900, 950 and 1000°C) and the cell performance was assessed at 700°C. Lower polarization resistance (RP) values were recorded for the cell produced at 900°C. The RP of the nano-composite cathodes was measured as lower (2.72 Ω-cm2 for the layered composites and 1.76 Ω-cm2 for the mixed composites) compared with LSMO. Hence, the results demonstrate the potential of using an LSMO-BSCMF composite in the mixed mode as a cathode for low temperature SOFCs to achieve a lower polarization potential.

8

Kobalt i jego związki . Metoda oznaczania w powietrzu na stanowiskach pracy

Wasilewski Paweł

Podstawy i Metody Oceny Środowiska Pracy

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2022

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Nr 1 (111)

133--145

PL

Kobalt ze względu na swoje fizykochemiczne właściwości w formie metalicznej jest wykorzystywany przy produkcji stopów odpornych na temperaturę, będących magnesami trwałymi i odlewniczych. Dodatkowo szerokie zastosowanie znajdują sole kobaltu, które są stosowane przy produkcji pigmentów, sykatyw do farb olejnych oraz baterii. Kobalt metaliczny w formie drobnego proszku w kontakcie ze skórą może wywoływać odpowiedź alergiczną. Głównym zagrożeniem dla zdrowia pracownika są rozpuszczalne sole kobaltu, które zgodnie z rozporządzeniem Parlamentu Europejskiego i Rady (WE 1272/2008) są sklasyfikowane jako substancje rakotwórcze. Celem badań było opracowanie metody oznaczania kobaltu do oceny narażenia zawodowego w zakresie 1/10 ÷ 2 zaproponowanej wartości NDS. Metoda polega na pobraniu aerozolu kobaltu i jego związków zawartych w powietrzu na filtr, mineralizacji filtra w kwasie azotowym(V) i kwasie chlorowodorowym w podwyższonej temperaturze, a następnie oznaczeniu zawartości kobaltu w próbce z zastosowaniem absorpcyjnej spektrometrii atomowej z elektrotermiczną atomizacją (ET-AAS). Podczas wykonywania badań spełniono wymagania walidacyjne przedstawione w normie europejskiej PN-EN 482. Metoda umożliwia oznaczanie kobaltu i jego związków w powietrzu w stężeniach 0,0001 ÷ 0,002 mg/m³ dla frakcji respirabilnej. Zakres tematyczny artykułu obejmuje zagadnienia zdrowia oraz bezpieczeństwa i higieny środowiska pracy będące przedmiotem badań z zakresu nauk o zdrowiu i inżynierii środowiska.

EN

Due to its physicochemical properties, cobalt in metallic form is used in the production of the following alloys: heat resistant, permanent magnets and foundry alloys. Moreover, cobalt salts are widely used in the production of pigments, oil drying agents and batteries. Metallic cobalt in the form of fine powder in contact with skin can cause an allergic response. However, the main danger are soluble cobalt salts, which are classified as carcinogens according to the European Union Commission Regulation (WE 1272/2008). The aim of this study was to develop a method for determining cobalt to assess occupational exposure within 1/10 ÷ 2 of the proposed MAC value. The method consists in taking an aerosol of cobalt and its compounds contained in the air onto a filter, mineralization of the filter in nitric acid (V) and hydrochloric acid at elevated temperature and then determination of cobalt content in the sample using atomic absorption spectrometry with electrothermal atomization (ET-AAS). Validation requirements presented in Standard No. PN-EN 482 were fulfilled during the tests. The method allow the determination of cobalt and its compounds in workplace air at concentrations of 0.0001 ÷ 0.002 mg/m³ for the respirable fraction. LOQ is 0.017 µg/m³ . The overall precision of the study was 5.39% and the expanded uncertainty was 23.56%. The method for determining cobalt and its compounds has been recorded in the form of an analytical procedure (see Appendix). This article discusses the problems of occupational safety and health, which are covered by health sciences and environmental engineering.

9

Separation of Co from Ni and Li from chloride media using polymer inclusion membrane system with thiosalicylate based ionic liquid

Pospiech Beata

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 152997

EN

The selective removal of cobalt(II) from aqueous chloride solutions containing nickel(II) and lithium(I) was studied. The facilitated transport of metal ions through polymer inclusion membranes (PIMs) with trihexyl(tetradecyl)phosphonium thiosalicylate [PR4][TS] under various conditions was analyzed. In order to optimize the separation process, several factors such as the ion carrier concentration in the membrane as well as of the effect of the concentration of the acids in the source/receiving phases were investigated. The results show that PIM containing 25% CTA as the polymer support, 40% NPOE as the plasticizer and 35% [PR4][TS] allow the selective recovery of more than 90% of cobalt(II) from 6 mol/dm3 hydrochloric acid into 0.5 mol/dm3 sulfuric acid.

10

Influence of Silicon and Cobalt Laser Alloying on the Microstructure and Nanomechanical Properties of the Gray Cast Iron Surface Layer

Paczkowska Marta

Journal of Research and Applications in Agricultural Engineering

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2022

|

Vol. 67, nr 2

13--19

EN

The aim of the research was to modify the surface layer of flakc iron by laser alloying with composition of elements: Si and Co and the evaluation of the obtained effects (regarding the changes in the surface layer microstructure and its chosen properties). In the first part, the treatment consist on covering the cast iron surface with the alloying composition layer, and in the second part – heating of this surface with laser beam using molecutar laser. The treatment effects were estimated with: SEM, EDS, hardness tester, nanoindentalion tester and surface profile device. Il was started (among others), that the alloyed zone in the surface layer flake iron after performed laser treatment was gained and it was characterized by following features (in comparison to the core material): fine and homogencous microstructure with some similarities to the hardened white cast iron, presence of Co and increased amount of Si. lt was noticed that such properties as hardness and Young's modulus have been increased.

11

Znaczenie alotropii wybranych pierwiastków chemicznych oraz polimorfizmu ich związków

Badora Aleksandra, Celińska Magdalena, Filipek Tadeusz

Przemysł Chemiczny

|

2021

|

T. 100, nr 2

168--172

PL

Wiele pierwiastków chemicznych oraz ich związków ma szerokie zastosowanie w produktach dostępnych na rynku. Są obecne zarówno w produktach żywnościowych, preparatach leczniczych, jak i w kosmetykach. Na podstawie przeglądu literatury i danych producenta dokonano analizy ich aktywności oraz potencjalnych korzyści i zagrożeń wynikających z ich stosowania. Przeanalizowano też wpływ tych substancji na środowisko naturalne.

EN

A review, with 35 refs., of chem. elements and their comps. used in foods, drugs and cosmetics. Their activity, potential benefits and risks as well as environmental impacts were taken into consideration.

12

Cobalt as a critical raw material

Potempa Martyna, Myćka Łukasz, Kortyka Łukasz, Madej Piotr, Sak Tomasz

Polish Technical Review

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2021

|

No. 3

2--9

EN

In the paper, the basic information on cobalt - the element classified, for many years, in the group of critical raw materials has been presented. The current demand on the mentioned metal is higher and higher, caused mainly by the development of new technologies and also, by energetic transformation, including a development of electric cars’ market. The subject connected with obtaining of critical raw materials is nowadays a key problem due to a high dependence of the EU countries on import. The obstructed access to raw materials may dramatically affect the break of the supply chain and, in consequence, affect negatively the manufacture of materials and equipment where cobalt is a component, increase the production costs and finally, limit technological development. The present article has a review character.

PL

W artykule przedstawiono podstawowe informacje na temat kobaltu, pierwiastka, zaliczanego od wielu lat do surowców krytycznych. Obecnie zapotrzebowanie na ten metal jest coraz większe, głównie z powodu rozwoju nowych technologii a także transformację energetyczną, w tym rozwój rynku samochodów elektrycznych. Tematyka związana z pozyskiwaniem surowców krytycznych jest obecnie kluczowa, ze względu na wysokie uzależnienie krajów Unii Europejskiej od importu. Utrudniony dostęp do surowców może drastycznie wpłynąć na przerwanie łańcucha dostaw, a co za tym idzie, wpłynąć negatywnie na produkcję materiałów i urządzeń w których kobalt stanowi składnik, podwyższyć jej koszta, a ostatecznie ograniczyć rozwój technologiczny. Artykuł ma charakter przeglądowy.

13

The Ion-Exchange Properties of Kaolinite in the Practice of Natural Water Purification

Pimneva Lyudmila A., Zagorskaya Alla A.

Ecological Engineering & Environmental Technology

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2021

|

Vol. 22, iss. 2

87--91

EN

The article examines the ability of natural clays to extract heavy metal ions from aqueous solutions by ion exchange. The process of extracting metal ions was considered on the example of the absorption of manganese, nickel and cobalt from natural waters. In order to study the chemical and mineralogical composition of natural kaolin, the following were used in the work: X-ray diffraction and X-ray phase methods, as well as IR spectroscopy. The article presents a comparative analysis of the adsorption of manganese, cobalt and nickel ions on natural kaolin under different temperature conditions. The nature of the interaction of the studied metal ions with kaolin was established. The results obtained on the adsorption of the ions under study show the efficiency of using natural kaolin clay for water purification.

14

Effect of Heavy Metal on the In vitro Growth of Paronchia argentea and its Antimicrobial Activity

Shatnawi Mohammad, Osman Nahid Abd Elhamid, Shibli Rida, Odat Nidal, Al-Tawaha Abdel Rahman, Qudah Tamara, Majdalawi Majdi

Ecological Engineering & Environmental Technology

|

2021

|

Vol. 22, iss. 3

142--151

EN

Paronchia argentea is traditionally being used for medicinal purposes in Jordan. The current investigation was designed to check the in vitro efficacy of in vitro and ex vitro P. argentea against selected bacterial and fungal strains. The antimicrobial properties of in vitro plantlets and field (ex vitro) plant extracts of P. argentea were investigated against both bacteria and fungi, after and before heavy metals stress used. In this study, four bacterial species were used: Listeria monocytogen and Staphylococcus aureus (Gram positive bacteria) Salmonella typhimurum and Coronobacter sakazakii (Gram negative bacteria) and Calvularia lunata as a mold. The obtained results revealed that the in vitro grown plantlets with the supplemented of lead (Pb), copper (Cu) or Cobalt (Co) with methanol and aqueous extract showed significant inhibitory activities within zones of inhibition ranging between 6.7-30.0 mm. All extracts of P. argentea had activity against the fungi and bacteria tested. The maximum inhibition zone was found in Staphylococcus aureus (30 mm inhibition zone) in medium supplemented with 0.3 mg/L Cu followed by Calvularia lunata (30.0 mm inhibition zone). The methanolic and aqueous P. argentea extract indicate that the solvent plays an important role in the solubility of the antimicrobial substance and also affects the activity of the microbe. Both field (ex vitro) and tissue culture plant extract showed similar antimicrobial activity. The present study could be used as an approach for the development of new, alternative and cheap antimicrobial drugs, particularly against the infections caused by the tested microbes through the tissue culture technology.

15

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

Drzeżdżon Joanna

Wiadomości Chemiczne

|

2020

|

[Z] 74, 5-6

423--437

EN

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

16

Gazy osłonowe do spawania niklu, kobaltu i ich stopów

Niagaj Jerzy

Stal, Metale & Nowe Technologie

|

2020

|

nr 5-6

58--64

PL

W artykule omówiono rodzaj i skład gazów używanych podczas spawania niklu, kobaltu i ich stopów, jak również opisano wpływ poszczególnych gazów na proces spawania i jakość złączy spawanych.

EN

The type and composition of gases used in welding of nickel, cobalt and their alloys are discussed, as well as the influence of shielding gases on welding process and quality of welded joints are described.

17

Commercial sponges in heterogeneous catalysis: developing novel composites with cobalt and silver

Żółtowska Sonia, Modelska Martyna, Piasecki Adam, Jesionowski Teofil

Physicochemical Problems of Mineral Processing

|

2020

|

Vol. 56, iss. 6

89--100

EN

The use of commercial sponges in materials science has gained much recent attention. Their unique properties, namely a fibrous, rigid skeleton, thermal stability and resistance to acid and basic hydrolysis, have been the primary motivation to use them in the development of new composites. In this work, a simple method of immobilization of cobalt and silver cations, followed by their reduction using sodium borohydride, was successfully applied for the first time to obtain functionalized spongin scaffolds. Three different materials, labeled Co_spongin, Ag_spongin and Co-Ag_spongin, were prepared. Their morphological and physicochemical properties were explored using various techniques (SEM+EDS, TG/DTA, FTIR). The focal point of the research was the application of the resulting materials in the reaction of 4-nitrophenol reduction with sodium borohydride in water. It was found that all of the composites possess superior activity in the reduction of 4-nitrophenol, achieving high rate constants of 0.31 min-1 for Ag_spongin, 0.52 min-1 for Co_spongin and 0.86 min-1 for Co-Ag_spongin. Reusability tests showed that all of the composites could be reused five times. Additional structural analysis after catalytic application showed no visible changes in the morphology of the catalysts. The results indicate that spongin can be considered as a facile, cost-effective, renewable and environmentally friendly three-dimensional support for use in heterogeneous catalysis.

18

Rapid sintering of TiB2 ceramics using Co as sintering aid under high pressure condition

Hu Meihua, Bi Ning, Liu Mingming, Gao Guangjin, Li Shangsheng, Su Taichao

Materials Science Poland

|

2020

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Vol. 38, No. 3

502--507

EN

The improved TiB2 ceramics were obtained in sintering process at the pressure of 5.5 GPa and temperature of 1550 °C in presence of metallic Co powder. The effect of Co content (ranging from 0 wt.% to 10.0 wt.%) on the phase composition, density, microstructure, Vickers hardness and thermal conductivity of TiB2 ceramics was analyzed. A small amount of new phase Co2 B has been created in the reaction of TiB2 and Co. The relative density of sintered TiB2 ceramics reached 98.1 %. When the mass fraction of Co increased, the porosity increased, while the hardness first increased and then decreased. The maximal Vickers hardness values were equal to 33.3 GPa or 28.2 GPa when the used load was of 4.9 N or 9.8 N, respectively. The highest reached value of thermal conductivity was 88.9 W∙m-1∙K-1. The dense TiB2 ceramics with improved hardness and thermal conductivity were ascribed to the high pressure sintering method and Co sintering aid. High pressure sintering method provides a new way for the preparation of ceramics materials.

19

Comparison of Copper and Cobalt Ions Sorption from Aqueous Solutions on Selected Sorbents

Bożęcka Agnieszka, Orlof-Naturalna Monika, Korpalski Aleksander

Journal of Ecological Engineering

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2020

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Vol. 21, nr 8

84--90

EN

In this paper, the sorption capacity of Norit SX2 activated carbon, ground rice husks and C‑160 ion exchange resin in relation to the Cu2+ and Co2+ ions was compared. The studied sorption processes were described using the Langmuir adsorption model. The C‑160 ion exchange resin was characterized by the highest affinity for both Cu2+ and Co2+ ions. It was shown that rice husk and active carbon are efficient sorbents in diluted solutions. The copper recovery for activated carbon, ion exchanger and rice husk was high. The efficiency of this process was 98.1%; 92.3% and 88.9%, respectively. Reducing the volume of acid used for regeneration allowed the solution to be concentrated and facilitated element recovery. Regeneration for cobalt occurred to a lesser extent.

20

Identyfikacja domieszek V, Co, Ni i Au w minerałach kruszcowych rud Fe-Ti-V (NE Polska) na podstawie analiz mikrosondą rentgenowską (EMPA)

Sadłowska Katarzyna, Mikulski Stanisław Z.

Przegląd Geologiczny

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2019

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Vol. 67, nr 3

192--195

EN

The main objective of this study was to quantitatively and qualitatively idenify trace metal admixtures in ore mineralsfrom Fe-Ti-V ore deposits within the Suwałki Anorthosite Massifin NE Poland. Chemical composition of ore minerals was determined using the CAMECA SX-100 electron microprobe and scanning electron microscope. The most abundant trace elements were Ti and Vhosted in oxides and Co, Ni, Cu, Zn contained in sulphides such aspentlandite, pyrrhotite, chalcopyrite, pyrite, siegenite, millerite. Scarce occurrences of native Bi, hessite and greenockite were identified. Samples, which were depleted in iron oxides were enriched in REE due to the presence of zircon, apatite and monazite.