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Abstract  

Results are presented on the low-temperature interaction of ammonia with AlPO-5, the TPD of the adsorbed ammonia and the high-temperature interaction of ammonia with the AlPO-5 framework.

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composition of the PM samples were analyzed by so-called temperature-programmed desorption followed by oxidation (TPD/O) experiments. During such experiments the samples were heated first under inert conditions (here: nitrogen atmosphere) to 700 °C with 20 K

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peak assignment software using Cu K α radiation (λ = 1.54 Å). All the diffraction patterns were recorded in 2θ range of 20–80° by a scanning rate of 2° min −1 . Temperature programmed desorption (TPD) experiments on 0.1 g of catalyst were

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Abstract  

Sol-gel-derived titania films were analyzed by temperature programmed desorption (TPD) and X-ray diffraction (XRD) techniques. The relationship between the TPD curves measured for two types of titania gel films and their crystal structures was investigated. On the basis of the analyses, a preparation process for a titania sol solution containing anatase nanocrystals was designed and developed. Using this process, a colloidal anatase titania sol solution was prepared by heating aqueous titanium hydroxide containing HCl at 60�C for 2 h. The nanocrystal structure of the titania films obtained by coating the sol on glass substrates was confirmed by TPD and XRD measurements.

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The interactions of propylene with zinc oxide have been studied by temperature-programmed desorption (TPD) under experimental conditions free of inter- or intraparticle limitations or readsorption phenomena.

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electron microscopy (SEM), X-ray powder diffraction (XRD), temperature program reduction (TPR), and temperature program desorption (TPD) techniques and catalytic measurements have been operated to determine their properties and catalytic performances

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Abstract  

The present work tries to emphasize the effect of acid/basis properties of montmorillonite type clays by ion exchange with cations of different natures. The acidity and basicity measuring was made by thermo programated desorption (TPD)1,2, using ammonia like basis agent and carbon dioxide like acid agent. With TPD method we can determine acid/basis proprietes by measuring of the quantity of the ammonia and carbon dioxide termodesorbed. Clays are crystalline aluminosilicates, similar with the zeolyts, who presents the property of ion exchanging. That propriety can be applicated for pollutants cations from aquatic solutions. Ion exchanging propriety depends of a lot of factors: the cation nature, the valence and the ionic ray of the cation present in the impregnated solution. That's an advantage for depollution process of heavy metals by fixing of these metals by montmorillonite structure. By using TPD metod we can obtaine a caracteristic diagram.

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Abstract  

Temperature-programmed desorption coupled with mass spectrometer as a detector (TPD), IR and 13C NMR measurements are used to study the adsorption of n-hexane on hydrated HZSM-5 and NH4ZSM-5 zeolites. The 13C NMR measurements show that n-hexane can access the pore structure of ZSM-5 zeolites previously saturated with water. TPD spectra of n-hexane are monitored in the temperature region 50–300C, in the case of fully or partially hydrated samples; two-stage desorption of n-hexane is found. Simultaneous desorption of water and n-hexane in the same temperature region are found, in all investigated samples.

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obtained by NH 3 -TPD on a Quantachrome Chembet 3000 chemisorb apparatus. In the first heating before NH 3 -TPD analyses, heating was carried out in He. The samples were first heated at 873 K for 1 h and then cooled to 423 K. Then NH 3 adsorption was

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Abstract  

DSC and TG-DTA techniques were used to investigate micro-sized silver powder particles and the adsorption of ethyl cellulose on these particles in a solution of ethyl acetate. The apparent specific heat of the silver particles was determined, and the kinetics of temperature-programmed desorption (TPD) of these adsorbed silver particles was investigated. Results show that the apparent specific heat and desorption kinetic parameters obtained by thermal analysis techniques could be used to characterize certain physico-chemical properties of such a particulate system.

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