2007年9月10日 · The acid properties of H-ZSM-5 zeolites with different SiO 2 /Al 2 O 3 ratios (30, 50, 80, 150, 280 and 1000) were examined by means of the temperature programmed desorption of ammonia (NH 3 -TPD).

Temperature Programmed Desorption (TPD) was first proposed by Amemiya and Cvetanovic in 1963. 1) In TPD, an adsorbent is adsorbed at equilibrium under predetermined conditions, and then the temperature is raised to a constant level. The molecules are desorbed when the thermal energy exceeds the adsorption energy of the pre-adsorbed molecules.

2018年11月26日 · The present work shows that NH3-TPD from Cu-CHA can be reconciled with copper complexes as NH3 storage sites. Temperature-programmed desorption (TPD) with ammonia is widely used for zeolite characterization revealing information on acidity and adsorption sites.

2001年10月1日 · The NH 3-TPD measurement shows a better resolution. We assign the LT peak essentially to the desorption of NH 3 molecules hydrogen-bound to NH 4 + cations. It can not be excluded, however, that the NH 3 held by strong Lewis …

2018年11月23日 · The NH 3-TPD experiment was performed by ramping temperature up from 200 to 550 °C, under a gas mixture of 8% CO 2, 7% H 2 O and balance N 2, at a rate of 10 °C/min. Note, that oxygen was excluded from the TPD gas mixture, to avoid oxidation of ammonia at elevated temperatures.

2019年2月1日 · Temperature-programmed desorption (TPD) with ammonia is widely used for zeolite characterization revealing information on acidity and adsorption sites. The interpretation of TPD measurements...

On the NH3-TPD curve of γ-alumina, two desorption peaks of ammonia centered at 237 and 335 °C were observed (Figure 3b).