Vacuum extractor with cryogenic concentration and capillary interface

Abstract

Abstract An apparatus and process for the vacuum distillation of volatile organic pollutants contained in various environmental sample matrices, such as sediments, soils, water and fish is connected to a cryogenic concentrating means. The volatile organic pollutants in the sample are first separated from the water vapors in the mixture which emanates from a sample chamber by condensing the water vapors in a precooling trap. The volatile organic compounds are first condensed in a cryogenic concentration trap which is subsequently warmed to transfer the volatile organic vapors to a cryogenic focusing trap cooled to -196 DEG C. A series of manually activated or automatically solenoid activated valves controls passage of the various fluids through a conduit network selectively connecting the various cooling traps and the outlet of a sample chamber to one another. A cooled pump oil trap may be connected into the conduit network to condense pump oil vapors and thus prevent pump oil contamination of the apparatus. A water sample or internal standards inlet is selectively connected by valve actuation to the outlet of the sample chamber. A carrier gas inlet and carrier gas and volatile extract outlet are respectively connected to the outlet of the cryogenic focusing trap by each of a set of 6-port valves. When the organic condensate in the cryogenic focusing trap is heated vapors of the volatile organic pollutants can be entrained within the carrier gas introduced from the inlet port and can be exited from the outlet port for qualitative or quantitative analysis by a gas chromatograph/mass spectrometer or gas chromatograph device which is interfaced by means of a capillary column with the cryogen condensing apparatus. The apparatus is particularly useful in monitoring pollutants in sediments, soils and in fish samples.

Inventors

• 👤 Michael H. Hiatt

Bibliographic Details