The impact of zeolite hierarchization is often highlighted in terms increased mesopore volume or specific surface area and preservation micropore volume. Yet, although these targets may be achieved, the accessibility to certain micropores might negatively affected during hierarchization. A set hierarchical MCM-22 based materials prepared on desilication treatments MCM-22, layered precursor MCM-...

Zeolite A and MCM-41 have extensive applications in basic science, petrochemical science, energy conservation/storage, medicine, chemical sensor, air purification, environmentally benign composite structure and waste remediation. However, the use of zeolite A and MCM-41 in these areas, especially environmental remediation, are restricted due to prohibitive production cost. Efficient recycling o...

Molecular dynamics (MD) simulations have been performed to investigate the rotational diffusive motion for 2-methyl butane (2-MeC4) and n-pentane (n-C5) in the cages of MCM-22 zeolite from 200-340 K. The rotation intermediate scattering function I(R) (Q,t) for 2-MeC4 and n-C5 confined in the supercages of MCM-22 was calculated. The dynamic scattering functions S(inc)(Q,omega) obtained via Fouri...

the fe-mcm-22 zeolite was found to be an efficient solid heterogeneous catalyst for synthesis of dihydropyrano [2,3-c] pyrazoles via one pot four component reaction of ethyl acetoacetate, hydrazine hydrate, aromatic aldehyde and malononitrile in aqueous alcohol. the catalyst was synthesized by hydrothermal method under autogenous pressure and modified by fe (iii) ion exchange. the prepared cata...

Zeolites are crystalline inorganic porous materials formed by TO4 tetrahedra (T=Si, Al, P, etc.) with ordered microporous structures. As a result of their tunable acidities and framework structures, zeolites have been used widely in catalysis and molecular adsorption/separation as well as several other emerging applications. However, the pore size of a zeolite is usually smaller than 2 nm, whic...

A new material MIT-1 comprised of delaminated MWW zeolite nanosheets is synthesized in one-pot using a rationally designed organic structure-directing agent (OSDA). The OSDA is comprised of a hydrophilic head segment that resembles the OSDA used to synthesize the zeolite precursor MCM22(P), a hydrophobic tail segment that resembles the swelling agent used to swell MCM22(P), and a di-quaternary ...

Pre-shaped mesoporous amorphous rice husk ash (RHA) and MCM-41 derived from RHA as a silica source were transformed into MFI-type zeolites using two different structure-directing agents. Tetrapropylammonium hydroxide (TPAOH) was utilized as an alkali source for silica dissolution and structure control during the direct transformation of RHA into zeolite. A monopropylamine (PA)-containing alkali...

The Fe-MCM-22 zeolite was found to be an efficient solid heterogeneous catalyst for synthesis of dihydropyrano [2,3-c] pyrazoles via one pot four component reaction of ethyl acetoacetate, hydrazine hydrate, aromatic aldehyde and malononitrile in aqueous alcohol. The catalyst was synthesized by hydrothermal method under autogenous pressure and modified by Fe (III) ion exchange. The prepared cata...

The Fe-MCM-22 zeolite was found to be an efficient solid heterogeneous catalyst for synthesis of dihydropyrano [2,3-c] pyrazoles via one pot four component reaction of ethyl acetoacetate, hydrazine hydrate, aromatic aldehyde and malononitrile in aqueous alcohol. The catalyst was synthesized by hydrothermal method under autogenous pressure and modified by Fe (III) ion exchange. The prepared cata...