Some applications of Freon-22 in supercritical fluid chromatographic analysis of environmental pollutants.
The applications of Freon-22 (R22) as a mobile phase and as a modifier in supercritical fluid chromatography were investigated. For the purpose of this investigation, the separation of eleven phenols listed by the United States Environmental Protection Agency as priority pollutants was studied. It was found that the use of neat R22 greatly reduced the retention times of the phenols compared with the use of neat carbon dioxide as mobile phase. Satisfactory separation of all the eleven phenols could be achieved using 5% R22 as modifier in carbon dioxide. The promising results obtained in this preliminary investigation indicate the potential for the use of R22 in supercritical fluid separation processes.
Department of Chemistry, National University of Singapore, Kent Ridge, 0511, Republic of Singapore.
S K
SK
Yeo
C P
CP
Ong
H K
HK
Lee
S F
SF
Li