Determination of micro amount of phenol and cresols in the atmosphere by using a filter impregnated with a solvent of alkali and glycerine

Abstract

A New procedure for the determination of trace phenol and cresols in the atmosphere was examined. A air sample was passed through a 17.3cm² of glass wool filter impregnated with a solution containing 10% sodium hydroxide and 30% glycerine at a rate of 5l/min. The phenol and cresol were collected quantitatively under the above conditions. The compounds absorbed on the filter were dissolved into ethyl ether and 10 N phosphoric acid mixture (5:1, v/v), the aliquot of the ethyl ether layer was introduced into a gaschromatograph with FID. The recovery of this procedure for the phenol and cresols were approximately 100%, the coefficients of variation in the determination of phenol or cresols were less than 7%. In the case of a extreme low concentration, the extract layer should be concentrated to a small volume and recovery of phenol or cresols was over 96%. The detection limits of this method were from 2.7 to 3.6 ppb for cresols and 3.3 ppb for phenol using a 500cm² alkali-glycerine filter for 5 min at an air flow rate of 120l/min. The detection limit was low enough to detect the smell limit. There were no interferences by other gases in this method and the phenol and cresols adsorbed in the filter could be kept for a long time without chemical change. This method was applied to the assay of the atomosphere near a foundry as a bad smell substance test and brough good results as well as simplicities in preparation, transportation, sampling, and storing samples.