نتایج جستجو برای: pb y zeolite
تعداد نتایج: 537509 فیلتر نتایج به سال:
An electron-rich zinc-modified zeolite Y material shows substantial activity for the decomposition of CO(2) to carbon with the release of O(2) at about 300 °C. It is elucidated that electrons delocalized in the vicinity of zinc cations in the zeolite material play an essential role in the decomposition reaction.
Preparative high pressure liquid chromatography on US-Y zeolite shape-selective molecular sieve was studied for carbon isotopic fractionation eects. We tested a standard mixture [17b, 21b(H)-hopane, 5a-cholestane] and complex natural hydrocarbon mixtures dominated by tetraand pentacyclic triterpenoids extracted from Oxford Clay shales. We con®rmed that steroids and hopanoids were separated on ...
Measurement by impedance spectroscopy of the changes in intrazeolitic cation motion of pressed pellets of zeolite particles upon adsorption of dimethylmethylphosphonate (DMMP) provides a strategy for sensing DMMP, a commonly used simulant for highly toxic organophosphate nerve agents. In this work, two strategies for improving the impedance spectroscopy based sensing of DMMP on zeolites were in...
The nitric oxide (NO) removal capacity of ion-exchanged zeolite Y obtained from coal combustion fly ash was evaluated in this work. Zeolite Y was exchanged either with Cu or Fe to obtain two different catalysts for the selective catalytic reduction of NOx from flue gas. The selective catalytic reduction experiments were carried out at temperatures ranging from 50°C to 350°C, water content 0% an...
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...
Fast (>I2 kHz) magic-angle-spinning NMR with IH' 7AI cross-polarization quantitatively monitors several aluminous species in dealuminated zeolite Y; the non-framework matter contains 4-, 5-and 6-coordinated A1 and the *7AI signal at 30 ppm is an independent resonance probably due to 5-coordinated non-framework Al and not part of a second-order quadrupole lineshape as previously reported. Since ...
MnTiO3-Zeolite-Y nanocomposites were synthesized with 5-10-20% (w/w) of MnTiO3 by stearic acid gel method. Then, the gels were calcined at 900 °C for 4 hours and the resulted spectra were investigated at 20% (w/w) concentration. Also, the presence of rhombohedral phase of MnTiO3 in Zeolite-Y matrix was confirmed by XRD, SEM, EDX and BET. The VSM results showed t...
2,4,6-Triphenylpyrylium cation encapsulated within zeolite Y promotes highly selective transformation of olefins to ketones with molecular oxygen, under visible light (lambda > 400 nm) irradiation at room temperature.
Catalyst S. Al-Khattaf* Chemical Engineering Department, King Fahd University of Petroleum & Minerals Dhahran 31261, Saudi Arabia Abstract Catalytic transformation of toluene has been investigated over Y-zeolite based catalysts in a novel riser simulator at different operating conditions. A number of experiments were carried out in the temperature range of 400-500C to understand the transformat...
Oxovanadium(IV), manganese(II) and copper(II) complexes of a Schiff base ligand derived from 2,4-dihydroxyacetophenone and 1,2-diaminocyclohexane have been encapsulated in the nanocavity of zeolite-Y by flexible ligand method and characterized by metal analysis, IR spectroscopic studies and X-ray diffraction patterns. The encapsulated complexes abbreviated here as CuL-Y, MnL-Y and VOL-Y catalyz...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید