PURPOSE:To eliminate the need for a pretreatment operation and to permit analysis with high determination accuracy by providing a precolumn housed in a heater which can be controlled in temp. between a sample injection port and column for analysis and providing stop valves which are respectively connected to the open atm. and carrier gas source between the column and the precolumn. CONSTITUTION:The precolumn 1 which is housed in the heater 4 and is constituted freely controllable in temp. is provided as a new addition between the sample injection port 3 and the column 2 for analysis at the time of providing the column 2 between the injection port 3 and a detector 10. A series flow passage consisting of the stop valve 5 which is connected to the carrier gas source 8 via the stop valve 9 and a flow rate control valve 11 and is connected to the open atm. 7 between the column 2 and the precolumn 1, the stop valve 6 connected to the gas source 8 and a flow rate control valve 12 is provided to the side of the port 3 opposite from the precolumn 1. The chromatograph is constituted in such a manner and only the sample fed into the port 3 and the solvent in the solvent contg. the desired component are expelled to the opening 7. The non-volatile component is stuck to the wall surface of the column 1. Only the induced component is sent to the column 2 and is analyzed.
