Wyniki wyszukiwania - Biblioteka Nauki

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: Heteropolyacids

Sortuj według:

Ogranicz wyniki do:

Supported H4SiW12O40 catalysts for α-pinene isomerization

100%

Szücs-Balázs J.-Z. , Coroş M. , Woiczechowski-Pop A. , Blăniƫă G. , Vlassa M.

Open Chemistry

2012

tom 10

nr 4

1208-1217

The heterogeneous isomerization of α-pinene was studied at 100, 130 and 160°C using 10% supported H4SiW12O40 (SiW) on SiO2, TiO2 and HZSM-5. The effect of the reaction temperature and the concentration of the catalyst over the conversion of α-pinene and the selectivity of camphene, limonene and terpinolene had been monitored. The recovery, reuse and leaching effect of the catalysts were studied. Simple, environmentally friendly and economic methods for the synthesis of camphene and limonene were developed and optimized. [...]

Acylation of aromatic compounds by acid anhydrides using Preyssler's anion [NaP5W30O110]14-and heteropolyacids as green catalysts

86%

Gharib A. , Jahangir M. , Scheeren J.

Polish Journal of Chemical Technology

2011

tom 13

nr 2

11-17

The Preyssler, Wells-Dowson and Keggin heteropolyacids are efficient and eco-friendly solid acid catalysts for the acylation of electron-rich aromatic compounds with acid anhydrides. The performance of different forms of heteropolyacids was compared. In all the cases, the best results were obtained using the Preyssler heteropolyacid as the catalyst. In the presence of 25 mol% (with respect to H+ equivalency) Preyssler catalyst, highly para-selective acetylation of anisole occurs using two equivalents of acetic anhydride, in 15 min at room temperature. The isolated yield of the p-methoxyacetophenone product is 98%.