Powiadomienia systemowe
- Sesja wygasła!
Tytuł artykułu
Autorzy
Treść / Zawartość
Pełne teksty:
Identyfikatory
Warianty tytułu
Konferencja
Proceedings of the 9th All - Polish Seminar on Mössbauer Spectroscopy OSSM'2012, 10-13 June 2012, Lublin - Kazimierz Dolny, Poland
Języki publikacji
Abstrakty
Fe1.xCox/MCM-41 nanocomposite materials were prepared by wet impregnation of the silica mesoporous support with aqueous solution of iron and cobalt salt mixtures. Samples, after calcination, were reduced at 573 K in order to obtain homogeneous distribution of (Fe-Co)3O4 oxide species over the MCM-41 support. Bimetallic systems were achieved through high temperature reduction, carried out at 1073 K. The temperature-programmed reduction studies indicated complex nature of the oxide species. The phase analysis of the obtained samples after low temperature reduction process carried out by means of X-ray diffraction method and using 57Fe Mossbauer spectroscopy revealed the presence of nanostructured magnetite- and maghemite-like phases. The samples with higher cobalt contents (x . 0.2) contained additionally bimetallic phases. The complete transformation of oxide phases to bimetallic Fe-Co systems occurred during reduction process in hydrogen at 1073 K. It was observed that high temperature processing caused partial transformation of highly dispersed iron oxide nanocrystallites into fayalite species embedded in the silica walls.
Czasopismo
Rocznik
Tom
Strony
87--92
Opis fizyczny
Bibliogr. 15 poz., rys.
Twórcy
autor
autor
autor
autor
- Maria Curie-Skłodowska University, Institute of Physics, 1 M. Curie-Skłodowskiej Sq., 20-031 Lublin, Poland, Tel.: +48 81 537 6220, Fax: +48 81 537 6191, zbigniew.surowiec@umcs.lublin.pl
Bibliografia
- 1. Ambashta RD, Yusuf SM, Mukadam MD, Singh S, Wattal PK, Bahadur D (2005) Physical and chemical properties of nanoscale magnetite-based solvent extractant. J Magn Magn Mater 293:8–14
- 2. Balat M, Balat M, Kırtay E, Balat Ha (2009) Main routes for the thermo-conversion of biomass into fuels and chemicals. Part 2: Gasification systems. Energy Convers Manage 50:3158–3168
- 3. Demirbas A (2008) Hydrogen production from carbonaceous solid wastes by steam reforming. Energy Sources Part A 30:924–931
- 4. Gac W, Goworek J, Wójcik G, Kępinski L (2008) The properties of gold catalysts precursors adsorbed on the MCM-41 materials modified with Mn and Fe oxides. Adsorption 14:247–256
- 5. Grün M, Unger KK, Matsumoto A, Tsutsumi K (1997) Ordered microporous/mesoporous MCM-41 type absorbents: novel routes in synthesis, product, characterisation and specification. In: McEnaney B, Mays JT, Rouquerol J, Rodriguez-Reynoso J, Sing KSW, Unger KK (eds)Characterization of porous solids IV. The Royal Society of Chemistry, London, pp 81–89
- 6. James OO, Chowdhury B, Mesubic MA, Maity S (2012) Reflections on the chemistry of the Fischer-Tropsch synthesis. RSC Adv 10:1–20 10 20 30 40 50Co content (%)0.00.20.40.60superparamagnetic phasemagnetite.8 maghemite Fe/CoBimetalic phase contributions92 Z. Surowiec et al.
- 7. Khan A, Smirniotis PG (2008) Relationship between temperature-programmed reduction profile and activity of modified ferrite-based catalysts for WGS reaction. J Mol Catal A: Chem 280:43–51
- 8. Li B, Xu J, Li X, Liu J, Zuo S, Pan Z, Wuc Z (2012) Bimetallic iron and cobalt incorporated MFI/MCM-41 composite and its catalytic properties. Mater Res Bull 47:1142–1148
- 9. Ma X, Sun Q, Ying W, Fang D (2009) Effects of the ratio of Fe to Co over Fe-Co/SiO2 bimetallic catalysts on their catalytic performance for Fischer-Tropsch synthesis. J Nat Gas Chem 18:232–236
- 10. Manova E, Paneva D, Kuneva B et al. (2009) Mechanochemical synthesis and characterization of nanodimensional iron-cobalt spinel oxides. J Alloys Compd 485:356–36
- 11. Moser A, Takano K, Margulies DT et al. (2002) Magnetic recording: advancing into the future. J Phys D 35:R157– R167
- 12. Surowiec Z, Wiertel M, Zaleski R, Budzyński M, Goworek J (2010) Positron annihilation study of iron oxide nanoparticles in mesoporous silica MCM-41 template. Nukleonika 55;1:91–96
- 13. Thünemann AF, Schütt D, Kaufner L, Pison U, Möhwald H (2006) Maghemite nanoparticles protectively coated with poly(ethylene imine) and poly(ethylene oxide)-block-poly(glutamic acid). Langmuir 22:2351–2357
- 14. Tronc E, Jolivet JP (1992) Interaction between charged particles. In: Dormann JL, Fiorani D (eds) Magnetic properties of fine particles. North-Holland Publishing, Amsterdam, pp 199–204
- 15. Tsoncheva T, Ivanova L, Paneva D, Mitov I, Minchev C, Fröba M (2009) Cobalt and iron oxide modified mesoporous zirconia: Preparation, characterization and catalytic behaviour in methanol conversion. Microporous Mesoporous Mater 120:389–396
Typ dokumentu
Bibliografia
Identyfikator YADDA
bwmeta1.element.baztech-article-BUJ8-0025-0052