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Abstract

Rare earth metals including yttrium and europium are one of several critical raw materials, the use of which ensures the development of the so-called high technology. The possibility of their recovery in Europe is limited practically only to secondary materials such as phosphogypsum and electronic waste.

The article presents the results of our research concerning the development of recovery technology of yttrium and europium from luminophore CRT used lamps. It describes the principle of separation of elements and the test results of cleaning the concentrate. It was shown that the costs of preparing the concentrate according to the proposed technology are lower than the phosphogypsum processing technology and the composition of the resulting product does not contain hazardous substances.

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Authors and Affiliations

Stefan Góralczyk
Elżbieta Uzunow
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Abstract

The presented work introduces a simple modification of coal fl y ash (FA) with 30% solution of H 20 2, used as a new efficient sorbent for the removal of organic dye crystal violet (CV) in the presence of Cu(II) ions in single- and bi-component systems Cu(II)-CV. FT-IR, TG, SEM-EDS, and XRD suggested that the mechanism of Cu(II) and CV sorption onto FA-H 2O 2 includes ion-exchange and surface adsorption process. Comparing the values of the reduced chi-square test (χ 2/DoF) and the determination coefficient R 2 obtained for CV of the considered isotherms, the fitting degree follows the sequence: Jovanović > Langmuir > Elovich > Freundlich > Redlich-Peterson (R-P) > Tóth > Halsey > BET. Sorption of Cu(II) ions in a single system by means of FA-H 2O 2 was well fi tted by the Langmuir and R-P model. The studies of equilibrium in a bi-component system by means of extended Langmuir (EL), extended Langmuir-Freundlich (ELF), and Jain-Snoeyink (JS) models were analysed. The estimation of parameters of sorption isotherms in a bi-component system Cu(II)-CV has shown that the best of fi t calculated values of experimental data for both sorbates have been the EL model and the JS model, but only in the case of a CV dye. The sorption kinetic of Cu(II) and CV onto FA-H 2O 2 was discussed by means of the PFO, PSO, and intra-particle diff usion models.
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Authors and Affiliations

Eleonora Sočo
1
Dariusz Pająk
1
Jan Kalembkiewicz
1

  1. Department of Inorganic and Analytical Chemistry, University of Technology, Rzeszów, Poland
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Abstract

The goal of this study is to develop a method of manufacturing porous ceramic skeletons used as semi-finished products for reinforcement of composite materials or as filters. For manufacturing skeletons, only waste materials from coal combustion (fly ashes and bottom slags) as well as rubber granules from used tires and car parts were used. These granules were a pore-forming agent that underwent thermal degradation during sintering process. The influence of sintering temperature, portion, and type of rubber granules on the porosity of developed ceramic skeletons was determined. The study of structure of base materials and the developed ceramic skeletons in a scanning electron microscope as well as their X-ray phase analysis were made. Results will allow to predict phases that can be formed on the metal-reinforcement interface during pressure infiltration.
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Authors and Affiliations

M. Krezmer
1
ORCID: ORCID

  1. Silesian University of Technology, Faculty of Mechanical Engineering, Scientific and Didactic Laboratory of Nanotechnology and Materials Technologies , Krasińskiego Str., 44-100 Gliwice, Poland
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Abstract

Odpady pogalwaniczne zaliczane są do odpadów niebezpiecznych. dlatego muszą być unieszkodliwiane. Jedną z najprostszych metod unieszkodliwiania jest zestalanie w spoiwach mineralnych. W niniejszej pracy przeprowadzono próby zestalania w zaprawie cementowej oraz w zaprawie cementowej z dodatkiem pyłów krzemionkowych odpadu powstałego po neutralizacji zużytych kąpieli do trawienia, rozcieńczonych wodami poplucznymi, pochodzącymi z procesu cynkowania oraz miedziowania drutu. Badania wykazały, że dodatek odpadów w ilości do 5% jest bezpieczny pod względem ekologicznym. Przy takiej ilości dodatku odpadów do cementu następuje nieznaczne obniżenie parametrów fizykomechanicznych, a metale są trwale irnmobilizowane w matrycy. Dodatek pyłów krzemionkowych w ilości 10% do cementu poprawiał cechy wytrzymałościowe wyrobów, ale wprowadzenie odpadów obniżało te parametry.
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Authors and Affiliations

Małgorzata Osińska
Agnieszka Ślosarczyk

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