61 62 63
REAGENTGRADE SOLVENTS
Figure 2. Plot of HETP vs. linear velocity for pyrene on a 0.30 mm i.d. (blue) and a 0.20 mm i.d. (green) column. The mobile phase was n-pentane at 210 °C and 32 atm
The high efficiency demonstrated above with capillary supercritical fluid chromatography is a good reason for pursuing this research. Other facts of importance also appear. For separations where both selectivity and high column efficiency are needed (e.g., resolution of certain isomeric substances), it may be of advantage that the interaction of solute and mobile phase molecules can be sensitively adjusted by pressure. In addition, while gradient elution techniques are needed to "program" solute retention in liq-
Users of Corco chromatographic, electronic and spectrophometric reagentgrade solvents know they can count on Corco for highest quality. Reliability. And delivery. In pints, gallons, five-gallons, or drums. At Corco, we've been specialists in reagent-grade solvents since 1953— and have built our reputation on meeting the requirements and specifications of our customers, ACS and ASTM. Corco can also provide reagentgrade acids, bases, and specialty chemicals. Write or call regarding your specific solvent requirements and our complete solvent listing in Bulletin 10. Or circle the number.
CORCO CHEMICAL CORPORATION Manufacturers of Reagent & Electronic Chemicals Tyburn Road & Cedar Lane · Fairless Hills, Pa. 19030 (215) 295-5006 CIRCLE 39 ON READER SERVICE CARD
Figure 3. Isobaric run of several PAH standards in a 0.20 mm i.d. X 58 m capillary column. Conditions were as in Figure 2. The standards were: 1) anthracene, 2) pyrene, 3) benzo[/c]fluoranthene, 4) benzo[e] pyrene, 5) dibenz[a,c]anthracene, 6) benzo[
