Abstract: A liquid chromatographic apparatus which removes air bubbles during preparatory operation for apparatus startup which includes a liquid feeding pump to feed a solvent, an injector to inject a sample into the solvent, a separation column to receive the solvent and the sample through the injector and separate the sample into components, a detector to detect the components supplied from the separation column, a pressure sensor to measure a pressure in a solvent flow channel of the liquid feeding pump, and a controller to control a purge operation for removing air bubbles in the solvent flow channel by the liquid feeding pump, judges whether a pressure change amount in the solvent flow channel measured by the pressure sensor during the purge operation is a specified change amount or larger, and completes the air bubble removal operation when the pressure change amount is the specified change amount or larger.

Abstract: Provided is a liquid chromatograph in which a solvent can be quickly replaced in a liquid delivery pump. The liquid chromatograph is provided with a liquid delivery pump 1 that takes in and discharges a solvent, and the liquid delivery pump is provided with: a pump head 111 in which an intake passage 10, a pressurizing chamber 12, and a discharge passage 103 are formed; a plunger 2; and a seal 61 that seals the pressurizing chamber. The liquid chromatograph 100 is configured such that a bottom dead center 21 of the plunger is disposed nearer to the upper end of the pressurizing chamber than the intake passage. The bottom dead center of the plunger may be disposed such that an upper surface of the plunger and a surface of the intake passage at the lower-end side of the pressurizing chamber are substantially the same.