Quantitative determination of phenols
The total phenolic content was determined by GC-MS after the
phenols had been derivatized to penta¯uorobenzoyl ethers. The
aqueous samples were adjusted to pH 10 by sodium hydrogencar-
bonate. Pentachlorophenol in hexane was added as internal stan-
dard, and an excess of penta¯uorobenzoyl bromide in hexane was
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then allowed to react under vigorous stirring for 10 min. All indi-
vidual phenols give the m/e-195 fragment as the base peak and the
response factors were set to 1. The phenols determined by this
method do not include phenolic acids.