Method of analysis of organic compounds in chromatography and apparatus for performing this method

An apparatus for performing a method of analysis of organic compounds , comprising:

• a surface-ionization detector including a housing, a thermoemitter made of a refractory material and having current leads, positioned in said housing and being in the form of a hollow cylinder accommodating a heating element about the lateral external surface thereof, a collector positioned in said housing by an insulator, extending coaxially with said thermoemitter and being in the form of a rod spaced from an inner ionizing surface of said thermoemitter throughout the length thereof, said ionizing surface being additionally coated with a layer of oxidized tungsten, and means for delivery of spent gases, mounted in said housing;
• a chromatographic column sealingly connected with said surface-ionization detector, the outlet end of the outlet portion of said chromatographic column being accommodated in said housing at the side thereof opposite to a securing of said collector in said housing of said surface-ionization detector, coaxially with said collector and adjacent to an end face of said collector and to said ionizing surface of said thermoemitter;
• means for feeding an auxiliary gas accommodated in the wall of said housing of said surface-ionization detector at the side of the accommodation therein of said end portion of said chromatographic column, for feeding the auxiliary gas adjacent to said ionizing surface of said thermoemitter.

A method of analysis of organic compounds in chromatography, including the steps of:

• separating chromatographically a gas mixture to be analyzed in the chromatographic column sealingly connected with a surface ionization detector;
• passing components of said separated mixture through said surface-ionization detector having a thermoemitter and a collector, said thermo-emitter being made of a refractory metal and having an ionizing surface coated with a layer of oxidized tungsten;
• passing concurrently an auxiliary gas through said surface-ionization detector;
• passing said components of said mixture under analysis and said auxiliary gas into said surface-ionization detector independently of one another and in one and the same direction;
• mixing each of said components with said mixture under analysis and said auxiliary gas in direct vicinity of the ionizing surface of the thermoemitter of said surface-ionization detector, the mixing of said components of said separated mixture under analysis and said auxiliary gas being conducted in quantity supporting substantial permanence of this surface-ionization factor of said thermoemitter of said surface-ionization detector within a predetermined range of working temperature thereof;
• and
• measuring ion current at the collector of said surface-ionization detector, and using the results of the measurements for assessing the presence and quantities of each of said components of said mixture under analysis.