PRESERVATION OF PHENOLIC COMPOUNDS IN WASTEWATERS

Copper sulfate and phosphoric acid with sample storage at 4°C is a common preservative technique used for phenolic compounds in wastewaters. However, there are no data showing its effectiveness. A study was conducted to compare the preservation method with the addition of strong base or acid and sample storage at 25 and 4°C. The addition of 2 mL conc H2SO4/L with sample storage at 4°C was most consistently effective in preserving stability for 3-4 weeks. However, the other chemical preservatives were effective for at least 8 days. Substantial loss of phenolic compounds rapidly occurred in all samples unless the chemical preservative was added immediately after sample collection. A positive correlation was found between loss of phenolic compounds and microbiological activity, suggesting the latter is the dominant factor in determining sample stability. © 1978, American Chemical Society. All rights reserved.