Liquid carbon dioxide delivery pump, and supercritical fluid chromatograph provided with the same

A supercritical fluid chromatograph comprising:

• a liquid carbon dioxide delivery pump comprising, a plunger pump head configured to deliver liquid carbon dioxide, wherein a refrigerant channel is provided inside the plunger pump head and is different from a channel in which liquid carbon dioxide flows, a circulation channel for refrigerant including the refrigerant channel, a refrigerant pump that is arranged on the circulation channel, the refrigerant pump being for causing the refrigerant to circulate through the circulation channel, a cooling section that is arranged on the circulation channel, at a position away from the pump head, the cooling section being configured to cool the refrigerant passing through the circulation channel, a temperature sensor for detecting an ambient temperature of the pump head or a temperature of the pump head, and a refrigerant pump control section for adjusting, based on a detection signal of the temperature sensor, a flow rate of the refrigerant pump so that liquid carbon dioxide flowing through the pump head is at a specific temperature;
• a modifier supply channel for supplying a modifier to a mobile phase channel to which liquid carbon dioxide is supplied by the liquid carbon dioxide delivery pump;
• a sample injection section for injecting a sample into an analysis channel at a downstream of a merging section of the mobile phase channel and the modifier supply channel;
• a separation column that is arranged at a downstream of the sample injection section;
• a back pressure valve that is arranged at a downstream of the separation column, the back pressure valve for maintaining a pressure at which a mobile phase in the separation column is in a supercritical fluid state;
• and
• a detector that is arranged between the separation column and the back pressure valve, or at a downstream of the back pressure valve.