Wincenty Turek

Changes in catalytic properties of substituted and unsubstituted heteropolyacids in conductive polymer matrix

Summary form only given. In this paper we reported results of our recent studies of substituted and unsubstituted , molecular dispersed heteropolyacids of Keggin and Dawson structure in conductive polymer matrix. The property of anions of PW/sub 12/O/sub 40/ and P/sub 2/W/sub 18/O/sub 62/ series has been tested. Due to its thermal stabilitys and possibilities of acid - base doping the polyaniline has been chopped as a conductive polymer carrier. The kinetic and spectroscopic study has been done. The degradation reaction of isopropanol has been chopped as a good model reaction to show the acid - base and redox properties of heteropolyacids.

The influence of acid–base and oxidation–reduction properties of nickel oxysalts on catalytic oxidation of propene

The catalytic activity of nickel oxysalts NiCo2O4 NiFe2O4, NiTiO3, NiMoO4, Ni3(PO4)2, with different ionic character of the oxygen bond in the anionic ligand was investigated. The acid–base and redox properties of selected catalysts were studied on the basis of kinetics of isopropyl alcohol conversion. The kinetics of propene oxidation over the catalysts and the activation energy and selectivity of oxidation reactions were determined. Activities of the catalysts in the propene oxidation reaction were compared with their oxidation–reduction and acid–base properties. The influence of the amount and form of chemisorbed oxygen on the propene oxidation pathway was investigated. Over the most active catalysts, the non-destructive propene oxidation towards acrolein is the least selective. Oxysalt catalysts active in oxidation reactions exhibit strong redox properties but direct the process towards destructive oxidation products.

Spectroscopic and catalytic studies of selected polyimines protonated with heteropolyacids

Abstract Aromatic poly(azomethines), namely unsubstituted polyazomethine (PPI) and ring substituted polyazomethine (PMOPI), prepared from p-phenylenediamine and the appropriate dialdehydes, have been protonated with heteropolyacids (H 3 PW 12 O 40 and H 3 PMo 12 O 40 ) in order to obtain new conjugated polymer supported catalysts. Detailed Raman and FTIR spectroscopic studies of the undoped and doped polymers have been performed. In i-propanol conversion these new catalysts exhibit predominantly redox activity producing acetone with high selectivity. The catalytic results are very similar to those obtained for polyaniline protonated with the same heteropolyacids showing that the insertion of HPA to the polymer matrix via the protonation reaction efficiently blocks their acid-base functions.

Doping of selected schiff polybases with heteropolyacids: catalytic properties of the products

Abstract It has been demonstrated that conjugated polyimines can serve as convenient catalytic supports on which catalytically active species can be molecularly dispersed using the dopin(protonation) reaction analogously as in the case of polyaniline. In particular, polyimine prepared via condensation of p -phenylenediamine and terephtalaldehyde can be protonated with 12-molybdophosphoric acid to give a new catalyst active in alcohol conversion. In isopropanol conversion this catalyst shows enhanced selectivity towards acetone formation as compared to unsupported crystalline heteropolyacid studied in the same experimental conditions.

Doping of selected schiff polybases and polyaniline with heteropolyacids: catalytic properties of the products

Summary form only given. Conjugated polymers, such as polyaniline or polyimines can serve as convenient supports on which catalytically active species can be deposited. In the preparation of such catalysts the doping technique typically used for the fabrication of conducting polymers can be employed. Thus poly imine prepared via condensation of p-phenylenediamine-and terephtalic aldehyde and polyaniline were doped with 12-molybdophosphoric acid in order to obtain new catalytic systems active in alcohol conversion. These new catalysts were characterized spectroscopically (FTIR, UV/VIS, EPR, ESCA) and their catalytic activity was determined in the test reaction of isopropyl alcohol conversion.