scholarly journals The Acidic Nature of Synthetic Zeolites: Acid Strength and Its Correlation with the Catalytic Activity

1969 ◽  
Vol 42 (9) ◽  
pp. 2449-2453 ◽  
Author(s):  
Hiroshi Otouma ◽  
Yoshimasa Arai ◽  
Hiroshi Ukihashi
Keyword(s):  
Catalytic Activity ◽  
Acid Strength ◽  
Synthetic Zeolites ◽  
Acidic Nature

Preparation of Strong Acid Catalysts by Sulfate Treatment of Calcined Boehmite

1992 ◽  
Vol 57 (11) ◽  
pp. 2241-2247 ◽  
Author(s):  
Tomáš Hochmann ◽  
Karel Setínek
Keyword(s):  
Catalytic Activity ◽  
Surface Area ◽  
Aluminum Sulfate ◽  
Solid Acid ◽  
Strong Acid ◽  
Acid Strength ◽  
Solid Acid Catalysts ◽  
Acid Catalysts ◽  
Preparation Methods ◽  
Indicator Method

Solid acid catalysts with acid strength of -14.52 < H0 < -8.2 were prepared by sulfate treatment of the samples of boehmite calcined at 105-800 °C. Two preparation methods were used: impregnation of the calcined boehmite with 3.5 M H2SO4 or mixing of the boehmite samples with anhydrous aluminum sulfate, in both cases followed by calcination in nitrogen at 650 °C. The catalysts were characterized by measurements of surface area, adsorption of pyridine and benzene, acid strength measurements by the indicator method and by catalytic activity tests in the isomerization of cyclohexene, p-xylene and n-hexane. Properties of the catalysts prepared by both methods were comparable.

Acid Strength of Heteropolyacids and Its Correlation with Catalytic Activity

1994 ◽  
Vol 67 (4) ◽  
pp. 1186-1188 ◽  
Author(s):  
Toshio Okuhara ◽  
Changwen Hu ◽  
Masato Hashimoto ◽  
Makoto Misono
Keyword(s):  
Catalytic Activity ◽  
Acid Strength

Natural zeolites for styrene oligomerization

Clay Minerals ◽  
2011 ◽  
Vol 46 (2) ◽  
pp. 189-195 ◽  
Author(s):  
S. Kowalak ◽  
A. Jankowska
Keyword(s):  
Catalytic Activity ◽  
High Activity ◽  
Acid Sites ◽  
The Other ◽  
Natural Zeolites ◽  
Pore Sizes ◽  
Other Hand ◽  
Synthetic Zeolites ◽  
Molecular Sizes

AbstractHydrogen forms of natural mordenite and clinoptilolite were used as catalysts for styrene oligomerization and as matrices to hold the resultant oligomers in order to prepare intense and light-resistant pigments. In contrast to synthetic zeolites of similar pore sizes (mainly H-ZSM-5, H-mordenite), the natural zeolites did not form products with an intense (pink) colouration. H-mordenite samples treated with styrene developed some colour due to styrene oligomers (the chromophore) whereas, in treated clinoptilolites, colour formation was negligible due to the lack of access of styrene molecules into the elliptical channels. The results of catalytic tests for cracking of cumene (cumene and styrene have similar molecular sizes) were consistent with the styrene oligomerization results. They indicate a noticeable catalytic activity with natural H-mordenite and a lack of activity with clinoptilolite. On the other hand, catalytic tests for propan-2-ol decomposition indicate a high activity with both natural zeolites, which confirms the presence of acid sites and their accessibility to small alcohol molecules.

Sign in / Sign up

Export Citation Format

Share Document