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001-es BibID:	BIBFORM114314
035-os BibID:	(cikkazonosító)13347 (WoS)001061107000001 (Scopus)85170252791
Első szerző:	Hajdú Viktória
Cím:	Amine Functionalization Leads to Enhanced Performance for Nickel- and Cobalt-Ferrite-Supported Palladium Catalysts in Nitrobenzene Hydrogenation / Viktória Hajdu, Ádám Prekob, Gábor Muránszky, Ferenc Kristály, Lajos Daróczi, Lajos Harasztosi, Zoltán Kaleta, Béla Viskolcz, Miklós Nagy, László Vanyorek
Dátum:	2023
ISSN:	1422-0067
Megjegyzések:	Easy preparation, good yield and easy recovery are the key challenges in the development of industrial catalysts. To meet all these three criteria, we have prepared intelligent, magnetizable NiFe2O4- and CoFe2O4-supported palladium catalysts that can be easily and completely recovered from the reaction medium by magnetic separation. The fast and facile preparation was achieved by a solvothermal method followed by sonochemical-assisted decomposition of the palladium nanoparticles onto the surface of the magnetic nanoparticles. The metal-support interaction was enhanced by amine functionalization of the supports using monoethanolamine. The performance and stability of the non-functionalized and amine-functionalized NiFe2O4- and CoFe2O4-supported palladium catalysts were compared in the industrially important nitrobenzene hydrogenation reaction. All catalysts showed high catalytic activity during aniline synthesis; complete nitrobenzene conversion and high aniline yield (above 97 n/n%) and selectivity (above 98 n/n%) were achieved. However, during reuse tests, the activity of the non-functionalized catalysts decreased, as the palladium was leached from the surface of the support. On the other hand, in the case of their amine-functionalized counterparts, there was no decrease in activity, and a non-significant decrease in palladium content could be measured. Based on these results, it can be concluded that amine functionalization of transition metal ferrites may result in more effective catalysts due to the enhanced metal-carrier interaction between the support and the precious metal.
Tárgyszavak:	Természettudományok Fizikai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk hydrogenation magnetic stable catalyst amine functionalized aniline
Megjelenés:	International Journal Of Molecular Sciences. - 24 : 17 (2023), p. 1-15. -
További szerzők:	Prekob Ádám Muránszky Gábor Kristály Ferenc Daróczi Lajos (1965-) (fizikus) Harasztosi Lajos (1962-) (villamosmérnök) Kaleta Zoltán Viskolcz Béla Nagy Miklós Vanyorek László
Pályázati támogatás:	GINOP-2.1.7-15-2016-00141 GINOP GINOP-2.3.4-15-2016-00004 GINOP C1759227 Egyéb
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001-es BibID:	BIBFORM119111
035-os BibID:	(cikkazonosító)4193 (WoS)001173675500010 (Scopus)85185444182
Első szerző:	Hatvani-Nagy Alpár Ferencz
Cím:	Bentonite as eco-friendly natural mineral support for Pd/CoFe2O4 catalyst applied in toluene diamine synthesis / Alpár F. Hatvani-Nagy, Viktória Hajdu, Ágnes Mária Ilosvai, Gábor Muránszky, Emőke Sikora, Ferenc Kristály, Lajos Daróczi, Béla Viskolcz, Béla Fiser, László Vanyorek
Dátum:	2024
ISSN:	2045-2322
Megjegyzések:	Toluene diamine (TDA) is a major raw material in the polyurethane industry and thus, its production is highly important. TDA is obtained through the catalytic hydrogenation of 2,4-dinitrotoluene (2,4-DNT). In this study a special hydrogenation catalyst has been developed by decomposition cobalt ferrite nanoparticles onto a natural clay-oxide nanocomposite (bentonite) surface using a microwave-assisted solvothermal method. The catalyst particles were examined by TEM and X-ray diffraction. The palladium immobilized on the bentonite crystal surface was identified using an XRD and HRTEM device. The obtained catalyst possesses the advantageous property of being easily separable due to its magnetizability on a natural mineral support largely available and obtained through low carbon- and energy footprint methods. The catalyst demonstrated outstanding performance with a 2,4-DNT conversion rate exceeding 99% along with high yields and selectivity towards 2,4-TDA and all of this achieved within a short reaction time. Furthermore, the developed catalyst exhibited excellent stability, attributed to the strong interaction between the catalytically active metal and its support. Even after four cycles of reuse, the catalytic activity remained unaffected and the Pd content of the catalyst did not change, which indicates that the palladium component remained firmly attached to the magnetic support's surface.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk 2,4-DNT Magnetic Ferrite Hydrogenation Stability
Megjelenés:	Scientific Reports. - 14 : 1 (2024), p. 1-9. -
További szerzők:	Hajdú Viktória Ilosvai Ágnes Mária Muránszky Gábor Sikora Emőke Kristály Ferenc Daróczi Lajos (1965-) (fizikus) Viskolcz Béla Fiser Béla Vanyorek László
Pályázati támogatás:	TKP2021-NVA-14 Egyéb
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001-es BibID:	BIBFORM117037
035-os BibID:	(cikkazonosító)16203 (WoS)001119803600001 (Scopus)85177758034
Első szerző:	Ilosvai Ágnes Mária
Cím:	Development of Polymer-Encapsulated, Amine-Functionalized Zinc Ferrite Nanoparticles as MRI Contrast Agents / Ágnes M. Ilosvai, LászlóForgách, Noémi Kovács, Fatemeh Heydari, Krisztián Szigeti, Domokos Máthé, Ferenc Kristály, Lajos Daróczi, Zoltán Kaleta, Béla Viskolcz, Miklós Nagy, László Vanyorek
Dátum:	2023
ISSN:	1422-0067
Megjegyzések:	The need for stable and well-defined magnetic nanoparticles is constantly increasing in biomedical applications; however, their preparation remains challenging. We used two different solvothermal methods (12 h reflux and a 4 min microwave, MW) to synthesize amine-functionalized zinc ferrite (ZnFe2O4-NH2) superparamagnetic nanoparticles. The morphological features of the two ferrite samples were the same, but the average particle size was slightly larger in the case of MW activation: 47 +/- 14 nm (Refl.) vs. 63 +/- 20 nm (MW). Phase identification measurements confirmed the exclusive presence of zinc ferrite with virtually the same magnetic properties. The Refl. samples had a zeta potential of -23.8 +/- 4.4 mV, in contrast to the +7.6 +/- 6.8 mV measured for the MW sample. To overcome stability problems in the colloidal phase, the ferrite nanoparticles were embedded in polyvinylpyrrolidone and could be easily redispersed in water. Two PVP-coated zinc ferrite samples were administered (1 mg/mL ZnFe2O4) in X BalbC mice and were compared as contrast agents in magnetic resonance imaging (MRI). After determining the r1/r2 ratio, the samples were compared to other commercially available contrast agents. Consistent with other SPION nanoparticles, our sample exhibits a concentrated presence in the hepatic region of the animals, with comparable biodistribution and pharmacokinetics suspected. Moreover, a small dose of 1.3 mg/body weight kg was found to be sufficient for effective imaging. It should also be noted that no toxic side effects were observed, making ZnFe2O4-NH2 advantageous for pharmaceutical formulations.
Tárgyszavak:	Természettudományok Fizikai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk fast microwave synthesis ferrite magnetic nanoparticles MRI zinc
Megjelenés:	International Journal Of Molecular Sciences. - 24 : 22 (2023), p. 1-8. -
További szerzők:	Forgách László Kovács Noémi Heydari, Fatemeh Szigeti Krisztián Máthé Domokos Kristály Ferenc Daróczi Lajos (1965-) (fizikus) Kaleta Zoltán Viskolcz Béla Nagy Miklós Vanyorek László
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