Many industrial applications of protonic zeolites as solid-acid heterogeneous catalysts rely on the strength or their Br nsted acidity, which (together with zeolite topology) affects both, catalytic activity and selectivity. Therefore, convenience to have an accurate (and simple) experimental technique for measuring acid strength. The enthalpy change, Delta H 0 , corresponding hydrogen bonding ...

Two NMR techniques, zH MAS NMR and echo Fourier 27AI NMR, have been applied for the first time to the investigation of Bronsted sites in dehydrated hydrogen forms ofzeolites. The “AI signal of SiOHAl sites, which was “NMR-invisible” until now, yields a quadrupole coupling constant C,,= 16 MHz for the dehydrated zeolite H-ZSM-5. The values of C,, determined from the ZH MAS NMR spectra of SiODAl ...

Growing CO2 emissions lead to global warming, which is currently one of the most challenging environmental phenomena. Direct catalytic hydrogenation dimethyl ether over hybrid catalysts enables utilization, hydrogen and energy storage produces sustainable fuels an important platform molecule. In this paper, we evaluated structure–performance correlations in bifunctional copper–zinc SAPO-34 for ...

Abstract Depletion of fossil fuels resources has triggered more research on finding potential alternative sources that are sustainable such as biomass waste. However, deconstruction the complex waste into desired products is too challenging and usually require a strong catalyst with great hydrolysing property. Common acids sulphuric acid, hydrochloric acid nitric were most studies for conversio...

The all-alkyl α-tertiary amino acid scaffold represents an important structural feature in many biologically and pharmaceutically relevant molecules. Syntheses of this class molecule, however, often involve multiple steps require activating auxiliary groups on the nitrogen atom or tailored building blocks. Here, we report a straightforward, single-step, modular methodology for synthesis esters....

The conversion of used lubricating oil towards fuel by catalytic is a suitable way to recycle waste oil. Catalyst has key role in conversion. Therefore this research was study the cracking oil, and thus its properties as an alternative for over aluminum fosfate. experiments were carried out batch microreactor at temperature 350-400 oC, atmospheric initial air pressure, 5% w/w catalyst concentra...

A new rapid and versatile approach using Ionic Liquid/DMSO as a chemical reagent for the synthesis of fused heterocyclic compounds in a highly efficient way is described. This method offers the advantages of proceeding in neutral conditions, giving high to excellent isolated yields (83-92%) for Niementowski synthesis with easy workup procedure. The inherent Bronsted acidity of ionic liquid and ...