Record Display for the EPA National Library Catalog


OLS Field Name OLS Field Data
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
Library Call Number Additional Info Location Last
NTIS  PB82-127366 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. 06/23/1988
Collation 7p
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%.