Jh. Knox et H. Ceylan, RELATIONSHIP BETWEEN ETHYLENE ADSORPTION-ISOTHERMS AND GC RETENTION ON CARBOWAX-COATED POROUS GRAPHITE, Chromatographia, 33(5-6), 1992, pp. 237-243
The objective of this work was to correlate adsorption isotherms of et
hylene at -78-degrees-C on porous graphitic carbon (PGC) with gas chro
matographic performance, the intention being that such isotherms could
be used as a quality control test for PGC's in general, whether used
for GC, HPLC or other adsorptive purposes. GC of test solutes shows th
at severe peak tailing on bare PGC is removed almost totally by a coat
ing PGC with as little as 0.05% by weight of Carbowax 1500. Surprising
ly there is little corresponding change in the ethylene adsorption iso
therms, although it is possible to distinguish small differences at su
rface coverages below 5 % of a monolayer of ethylene. Further work is
required to establish a useful QC test.