Hydrophobic dipeptide crystals: A promising Ag-free class of ultramicroporous materials showing argon/oxygen adsorption selectivity

• Type: Article in International Scientific Journal
• Date: 2014

Authors

R. Afonso (Author) FEUP; A. Mendes (Author) FEUP; L. Gales (Author) FEUP

Journal

Title: Physical Chemistry Chemical Physics

Vol. 16 No. 36

Pages: 19386-19393

ISSN: 1463-9076

Publisher: Royal Society of Chemistry

Indexing

ISI Web of Knowledge - 14 Citations

ISI Web of Science

Scopus - 15 Citations

INSPEC

Scientific classification

FOS: Engineering and technology > Chemical engineering

CORDIS: Technological sciences > Engineering > Chemical engineering

Associated Projects

PTDC/EQU-EQU/114944/2009 - Desenvolvimento de um sistema autorregenerativo para a remoção de CO2 de sistemas anestésicos em circuito fechado

HPOVPSA - High-Performance Oxygen Vacuum Pressure Swing Adsorption

Other information

Authenticus ID: P-009-SQG

DOI: 10.1039/c4cp02085e

Abstract (EN): The adsorption isotherms of nitrogen, oxygen and argon in four VA-class hydrophobic dipeptides are presented. Isotherms were determined at 5, 20 and 35 1C, for a pressure range of 0–6 bar. Under these conditions, adsorption is still in the Henry region. For all materials and temperatures, the sequence of preferential adsorption is Ar 4 O2 4 N2, a highly abnormal result. At 5 1C, the dipeptide with the smallest pores, VI, has Ar/O2 adsorption equilibrium selectivities up to 1.30, the highest ever measured in Ag-free adsorbents. Gas uptakes, at 1 bar and 20 1C, are B0.05 mol kg1 , very low relative values that are partially explained by the low porosity of the solids (o10%). The significance of these results for the development of new materials for the process of O2 generation by pressure swing adsorption (PSA) is discussed. The results indicate some of the structural and chemical properties that prospective Ag-free adsorbents should have in order to have Ar/O2 selectivity, hydrophobic pores, less than 0.5 nm-wide, and porosity of, at least, 20%.

Language: English

Type (Professor's evaluation): Scientific

Notes: Publicação abrangida pelo Journal Citation Reports 2015

No. of pages: 8