Development of a Chemical Method for Detecting Petrogenic Hydrocarbons in the Presence of Biogenic Hydrocarbons Down to the 5 PPB Level.

摘要

The purpose of this project was to develop a chemical method for detecting petrogenic hydrocarbons in the presence of biogenic hydrocarbons at levels below those causing biological harm. The method developed involves use of high pressure liquid chromatograph using chloroform as the solvent and measuring fluorescence in the range of 418 nm after excitation at 403 nm. The method is capable of detecting petroleum hydrocarbons in the presence of overwhelming amounts of biological material. It has been demonstrated that the fractions of oil which fluorescence at 418 nm after excitation at 403 nm are among the most persistant fractions in crude oil. Of the six crude oils investigated, Saudi Arabian was the least responsive to the above technique and yet was still detectable in quantities of less than 0.1 microgram and easily quantifiable at 1 microgram. Under these circumstances oil is detectable in the ppb range using small to moderate sized water samples (one liter or less). It has been reported that an oil concentration of 5.5 ppb in water would be harmless to the biological community and, therefore, the newly developed method is capable of detecting oil below toxic levels.