Upon liquid phase adsorption of C1-C5 primary alcohols on high silica MFI zeolites (Si/Al = 11.5-140), the concentration of adsorbed molecules largely exceeds the concentration of traditional adsorption sites: Brønsted...
The development of a low temperature (À 160 °C) NO adsorption technique is disclosed that avoids the chemical conversion of the probe molecule at room temperature. The observed IR peaks for Cu + (NO) 2 and Cu 2 + (NO) species can be used to quantify the amount of exchanged copper species in a broad range of samples, including a wash-coated honeycomb. Calibration curves for Cu + (NO) 2 and Cu 2 + (NO) are determined for copper loadings up to 3.99 wt% with Silica-to-Alumina Ratio (SAR) of 16-22, and quantitative agreement with the complementary hydrogen Temperature Programmed Reduction (H 2 -TPR) results is established. This methodology allows to identify different Cu species in Cu-CHA, such as Z 2 Cu(II), Z 1 Cu(II)OH and Cu dimers, based on their distinct IR signatures. In addition, the perturbed TÀ OÀ T framework vibration -characterized at 400 °C -can also be used as a complimentary method to quantify Z 2 Cu(II) species.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.