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001			599056
005			20231030033815.0
035			_a(RuTPU)RU\TPU\tpu\22885
035			_aRU\TPU\tpu\22884
090			_a599056
100			_a20130321a2002 k y0engy50 ba
101	0		_aeng
102			_aNL
200	1		_aOn the nature of the silver phases of Ag/Al2O3 catalysts for reactions involving nitric oxide _fN. Bogdanchikova [et al.]
330			_aThe nature of the silver phases of Ag/Al2O3 catalysts (prepared by silver nitrate impregnation followed by calcination) was investigated by X-ray diffractograms (XRD), transmission electron microscopy (TEM) and UV–VIS analyses and related to the activity of the corresponding materials for the oxidation of NO to NO2. The UV–VIS spectrum of the 1.2 wt.% Ag/Al2O3 exhibited essentially one band associated with Ag+ species and the NO2 yields measured over this material were negligible. A 10 wt.% Ag/Al2O3 material showed the presence of oxidic species of silver (as isolated Ag+ cations and silver aluminate), but the UV–VIS data also revealed the presence of some metallic silver. The activity for the NO oxidation to NO2 of this sample was moderate. The same 10% sample either reduced in H2 or used for the C3H6-selective catalytic reduction (SCR) of NO showed a significantly larger proportion of silver metallic phases and these samples displayed a high activity for the formation of NO2. These data show that the structure and nature of the silver phases of Ag/Al2O3 catalysts can markedly change under reaction feed containing only a fraction of reducing agent (i.e. 500 ppm of propene) in net oxidizing conditions (2.5% O2). The low activity for N2 formation during the C3H6-SCR of NO (reported in an earlier study) over the high loading sample can, therefore, be related to the presence of metallic silver, which is yet a good catalyst for NO oxidation to NO2. The reverse observations apply for the oxide species observed over the low loading sample, which is a good SCR catalyst but do not oxidize NO to NO2.
333			_aВ фонде НТБ ТПУ отсутствует
461			_tApplied Catalysis B: Environmental _d1992-
463			_tVol. 36, iss. 4 _vP. 287-297 _d2002
610	1		_aтруды учёных ТПУ
701		1	_aBogdanchikova _bN.
701		1	_aMeunier _bF. C.
701		1	_aAvalos-Borja _bM.
701		1	_aBreen _bJ. P.
701		1	_aPestryakov _bA. N. _cChemist _cProfessor of Tomsk Polytechnic University, Doctor of Chemical Science _f1963- _gAleksey Nikolaevich _2stltpush _3(RuTPU)RU\TPU\pers\30471 _4070
801		1	_aRU _b63413507 _c20130226
801		2	_aRU _b63413507 _c20130321 _gRCR
942			_cBK