Head-space gas-chromatographic determination of 2-alkyl-5,5-dimethyl-1,3-dioxane derivatives in wastewaters of a polyester resin plant

The static headspace gas chromatographic technique can be conveniently employed to check the presence and amount of the odorous side-products, 2-R-1,3-dioxanes (R = H, CH3, C2H5, i-C3H7, n-C3H7), directly from the wastewaters flowing from the reactors during the synthesis of polyester resins. By the optimisation of a simple and direct analytical method, the amounts of these compounds may be continuously monitored and controlled. This method is characterized by good repeatability (3–4%) and does not seem to suffer from matrix effects. The detection limits for the determination of the five dioxanes fall in the range 400–700 mg dm23 (alfa=beta=0.05).