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001-es BibID:	BIBFORM112576
035-os BibID:	(WoS)000785165700001 (Scopus)85127768738
Első szerző:	Győri Enikő (vegyész)
Cím:	Environment-Friendly Catalytic Mineralization of Phenol and Chlorophenols with Cu- and Fe- Tetrakis(4-aminophenyl)-porphyrin-Silica Hybrid Aerogels / Enikő Győri, Ádám Kecskeméti, István Fábián, Máté Szarka, István Lázár
Dátum:	2022
ISSN:	2310-2861
Megjegyzések:	Fenton reactions with metal complexes of substituted porphyrins and hydrogen peroxide are useful tools for the mineralization of environmentally dangerous substances. In the homogeneous phase, autooxidation of the prophyrin ring may also occur. Covalent binding of porphyrins to a solid support may increase the lifetime of the catalysts and might change its activity. In this study, highly water-insoluble copper and iron complexes of 5,10,15,20-tetrakis(4- minophenyl)porphyrin were synthesized and bonded covalently to a very hydrophilic silica aerogel matrix prepared by co-gelation of the propyl triethoxysilyl-functionalized porphyrin complex precursors with tetramethoxysilane, followed by a supercritical carbon dioxide drying. In contrast to the insoluble nature of the porphyrin complexes, the as-prepared aerogel catalysts were highly compatible with the aqueous phase. Their catalytic activities were tested in the mineralization reaction of phenol, 3-chlorophenol, and 2,4-dichlorophenol with hydrogen peroxide. The results show that both aerogels catalyzed the oxidation of phenol and chlorophenols to harmless short-chained carboxylic acids under neutral conditions. In batch experiments, and also in a miniature continuous-flow tubular reactor, the aerogel catalysts gradually reduced their activity, due to the slow oxidation of the porphyrin ring. However, the rate and extent of the degradation was moderate and did not exclude the possibility that the as-prepared catalysts, as well as their more stable derivatives, might find practical applications in environment protection.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk silica aerogel aerogel hybrid covalent immobilization porphyrin complexes heterogeneous catalyst phenol mineralization chlorophenol mineralization
Megjelenés:	Gels. - 8 : 4 (2022), p. 202-. -
További szerzők:	Kecskeméti Ádám (1992-) (vegyész) Fábián István (1956-) (vegyész) Szarka Máté (1990-) Lázár István (1959-) (vegyész)
Pályázati támogatás:	GINOP-2.3.2-15-2016-00041 GINOP GINOP-2.2.1-15-2017-00068 GINOP GINOP-2.3.2- 15-2016-00008 GINOP GINOP-2.3.3-15-2016-00004 GINOP 17-124983 OTKA K127931 Egyéb GINOP-2.3.3-15-2016-00029 GINOP
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM081372
035-os BibID:	(cikkazonosító)26
Első szerző:	Lázár István (vegyész)
Cím:	A Continuous Extraction and Pumpless Supercritical CO2 Drying System for Laboratory-Scale Aerogel Production / István Lázár, István Fábián
Dátum:	2016
ISSN:	2310-2861
Megjegyzések:	Production of aerogels starts with solution chemistry and may end with supercritical carbon dioxide drying, which both require a specialized system. Here we present a complete aerogel production system that was developed and used in our laboratory over the last nine years. Our aim was to develop a supercritical dryer and a protocol, whereby the CO2 pump can be left out, and the entire flow system is operated by the pressure of the CO2 cylinder. Drying pressure and temperature are controlled by the combination of the filling and heating temperatures. A continuous-mode solvent exchange system has also been developed, in which the solvent consumption during the process can be reduced to one-third of the batch method. In the new medium temperature 1.5 L volume supercritical dryer, the temperature is set to a constant 80-82 °C, and the pressure can be in the 90-200 bar range, depending on the conditions. We have performed approximately 200 dryings thus far, and prepared a wide range of monolithic aerogels, from pristine silica aerogels to polysaccharides and collagen. In this paper, we have summarized not only the technical details, but also the work experiences, as well as advantages and disadvantages of the systems.
Tárgyszavak:	Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk aerogel production supercritical CO2 drying continuous solvent extraction liquid CO2 extraction medium temperature process
Megjelenés:	Gels. - 2 : 4 (2016), p. 1-15. -
További szerzők:	Fábián István (1956-) (vegyész)
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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