A facile and convenient protocol was developed for the fast (2.5-3.5 h) and high yielding (70-90%) synthesis of fused 1,4-dihydropyridines from dimedone in the presence of HY-zeolite as an efficient recyclable heterogeneous catalyst.

The escalating cost of Pt metal has prompted researchers to incorporate other metals into Pt/catalysts reduce the amount Pt. In this work, several bimetallic Pt-Zr/HY-zeolite catalysts were prepared by incorporating small amounts inexpensive Zr Pt/HY-zeolite form an active and selective catalyst. Results showed that although half required platinum was used, catalytic activity Pt-Zr/HY catalyst ...

We have modeled the formation kinetics of nitrogen-substituted (nitrided) zeolites HY and silicalite; we have also modeled the stability of nitrided sites to heat and humidity. These kinetic calculations are based on mechanisms computed from DFT-computed pathways reported in our previous work. Reactant ammonia and product water concentrations were fixed at various levels to mimic continuous nit...

Inflammatory bowel disease (IBD) is induced by multiple environmental factors, and there is still no known treatment capable of curing the disease completely. We propose a zeolite-containing mixture (Hydryeast®, HY)-a multi-component nutraceutical of which the main ingredients are Azumaceramics (mixture of zeolite and oyster shell burned under high temperature), citric acid, red rice yeast (mon...

High-resolution O multiple-quantum MAS (MQMAS) NMR spectra have been obtained for zeolite HY in order to study its local structure and Brønsted acidity. The O NMR signals due to all the different oxygen environments have been observed in one single experiment, including the readily-resolved signals arising from the two types of oxygen atoms of the zeolite framework (Si–O–Al and Si–O–Si), and ox...

Introduction An understanding of how CO2 and H2O interact and affect each other’s behavior on adsorbent surfaces is essential for both theoretical study and industrial processes especially CO2 capture from wet flue gas streams. There are few reported studies on adsorption equilibrium for such a binary system. Rege and Yang [1] measured very low concentration of CO2/H2O vapor (<4.1% relative hum...

Thermal decomposition in a thermobalance of Fe(CO), adsorbed on alkali-metal, hydrogen-Y, dealuminated Y, L and omega zeolites proceeds stepwise via slow decarbonylation at low and high temperatures, separated by a fast endothermic reaction. Average CO/Fe ratios have been determined after each step. From i.r. results the former intermediates are assigned to species bearing bridging CO, whereas ...

Palm oil is a promising raw material for biofuel production using the simultaneous catalytic mechanism of bifunctional cracking-deoxygenation reactions. Through process, chains palmitic acid and oleic in palm were converted to diesel-range hydrocarbons. The combination effects CaCO3 HY zeolite enhanced into biofuel, because increasing basic sites catalysts due synergistic roles HY. introduction...