Recently, hybrid materials using poly ethylene glycol and porous nanocrystals have been developed for drug release. In this study, a series of poly ethylene glycol (PEG)/NaY zeolite and PEG/MCM-41 nanocomposites get synthesized. These materials are characterized using FT-IR spectroscopy, XRD, TGA and SEM. After loading the metronidazole onto these nanocomposites, the release of Metronidazole wa...

Dye-exchanged Y zeolite is shown to be an effective medium to control the stereoselectivity in the photooxygenation of chiral oxazolidinone-functionalized Z/E-1 enecarbamates. An enantioselectivity (ee) as high as 80% was observed in the methyldesoxybenzoin (MDB) product, obtained in the methylene-blue-exchanged NaY zeolite at room temperature. The efficacy of the asymmetric induction in the MD...

background: formaldehyde is one of the most serious air contaminant that can be found everywhere. some of the source of formaldehyde include product of building materials, decorated materials, cigarette smoke, etc. aldehydes compounds especially formaldehyde are used as disinfectants for sterilization in different industries. in this study we measured formaldehyde workplace exposure with niosh ...

While microwave enhancement of chemical syntheses has been demonstrated for a broad variety of chemical reactions, there is no accepted universal mechanism. Is the enhancement due to more efficient heating, to overheating, to nonuniform heating, or to nonthermal effects? Analyses are complicated due to the often significant spatial and temporal temperature variations in microwave reactor system...

The ion exchange of Na for Cr/K, Cr/Mg and Cr/Ca in Y and X zeolites was studied using breakthrough curves. It was observed that Cr ions were able to remove some competitive ions that had already been exchanged at the zeolitic sites, producing a sequential ion exchange. Some mass transfer parameters such as length of unused bed, overall mass transfer coefficient, operational ratio and dimension...

Methanol is an important feedstock in numerous catalytic processes. It can be produced via Fischer-Tropsch reaction from synthesis gas [1] and its further transformation to hydrocarbons up to C10 is the basis of several industrially important reactions as for instance the Methanol to Gasoline process [2]. Methanol can also be used as an alkylating agent for aromatic compounds in zeolite-catalys...

The investigation on the modification of NaY zeolite on LaHY and AEHY (AE refers Ca and Sr and the molar ratio of Ca and Sr is 1:1) zeolites was proformed by XRD, N2-physisorption (BET), XRF, XPS, NH3-TPD, Py-IR, hydrothermal stability, and catalytic cracking test. These results indicate that HY zeolite with ultra low content Na can be obtained from NaY zeolite through four exchange four calcin...

We focus on the analysis of N(2) adsorption on NaY faujasite investigated by means of both the FTIR and volumetric measurements. We examine how these two approaches, when combined, can lead to a more advanced quantitative description featuring the understanding of gas adsorption both at the molecular and the macroscopic scales. For this task, we describe hereafter the method used and how we cir...

The spin-lattice relaxation time T\ of 2 , N a N M R in dehydrated zeolite NaY has been measured from 26 to 300 K. The magnetization recovery curve is not single-exponential at all measured temperatures and 1 increases in proportion to the square of temperature above 200 K. The result is analyzed with a theory of the Raman process based on covalency. The value of T\ is compared with that of NaX...

Organometallic complexes hosted inside porous frameworks are particularly interesting because of possible application in heterogeneous catalysis or electronic devices and optical materials. We present here a detailed spectroscopic investigation on the structure and reactivity towards simple reagents (such as CO) of chromocene molecules (Cp2Cr) encapsulated into the nanovoids of two different ma...