Main Title |
Foam Prevention in Purge and Trap Analysis. |
Author |
Erickson, Mitchell D. ;
Alsup, Martin K. ;
Hyldburg, Patricia A. ;
|
CORP Author |
Research Triangle Inst., Research Triangle Park, NC.;Environmental Monitoring and Support Lab., Cincinnati, OH. |
Year Published |
1981 |
Report Number |
EPA-68-03-2749; EPA-600/J-81-380; |
Stock Number |
PB82-127366 |
Additional Subjects |
Water analysis ;
Foam ;
Antifoaming agents ;
Laboratory equipment ;
Revisions ;
Sampling ;
Organic compounds ;
Water pollution ;
Chemical analysis ;
Reprints ;
Water pollution detection ;
Procedures
|
Holdings |
Library |
Call Number |
Additional Info |
Location |
Last Modified |
Checkout Status |
NTIS |
PB82-127366 |
Some EPA libraries have a fiche copy filed under the call number shown. |
|
07/26/2022 |
|
Collation |
7p |
Abstract |
Volatile organics are often separated from water samples by bubbling an inert gas through the water and collecting the organics on a sorbent trap, a technique known as purge and trap. Unfortunately, during the analysis of many water samples, foam can climb through the apparatus and contaminate the trap. This research project has investigated both chemical and mechanical antifoaming techniques. A total of 27 potential chemical antifoaming agents were evaluated for their ability to control foam. Two silicone-based commercial antifoam emulsions, Dow Corning Antifoam C and General Electric AF-72, were rated superior overall. The final protocol specifies use of 2 drops of purified silicone antifoam emulsion (General Electric AF-72) in a 5.0-mL sample which is purged in a 60-mL purge flask. The procedure was validated with seven volatile compounds (29-159 ng) spiked into four wastewaters. Mean recovery (vs. purge of distilled water) was 97%. |