Spin conversion of hydrogen using supported iron catalysts at cryogenic temperature

• Published in: Cryogenics (Guildford) Vol. 69; pp. 36 - 43
• Main Authors: Das, Taraknath, Kweon, Soon-Cheol, Nah, In Wook, Karng, Sarng Woo, Choi, Jeong-Gil, Oh, In-Hwan
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2015
• Subjects: Aluminum oxide; Catalysis; Catalysts; Conversion; Cryogenic temperature; Crystallites; FeAl; FeCe catalysts; FeTi; In situ FTIR; Iron oxides; Ortho–para hydrogen spin conversion; Raman; SEM; Wetness; XRD; FeCe catalysts; FeTi; In situ FTIR; Raman; SEM; FeAl; XRD; Ortho–para hydrogen spin conversion; Cryogenic temperature
• ISSN: 0011-2275; 1879-2235
• DOI: 10.1016/j.cryogenics.2015.03.003

In situ FTIR system for the spin conversion of liquid phase orthohydrogen to parahydrogen. [Display omitted] •In situ FTIR spectroscopy for spin conversion of hydrogen.•Ortho to para hydrogen spin conversion at cryogenic temperature.•Supported iron oxide catalysts are active at low temperature.•The most active catalyst was 10–20wt% iron oxide supported on alumina. Alumina-supported iron oxides have been prepared by incipient wetness impregnation method and employed for orthohydrogen to parahydrogen spin conversion at cryogenic temperature. These materials were characterized using a series of characterization techniques such as SEM, XRD, Raman and in situ FTIR spectroscopy. The spin conversion was investigated at low temperature by a batch mode of operation. The in situ FTIR spectra were collected in a transmission mode to obtain the spin conversion. While the iron oxide was highly dispersed over alumina support at low loading percent, a rodlike crystallite of iron oxide was formed at high loading percent. The 10 and 20wt% iron oxides on alumina were proved to be the most active catalysts. The spin conversion process was very slow and time-dependent. It was concluded that the spin conversion was a function of various factors including the iron oxide loading percent, calcination temperature, and different supports.