A method and a rotary valve in a continuous chromatography system. The rotary valve comprises a stator with an inner stator face, and a rotor with an inner rotor face arranged in sealing contact with the inner stator face. The stator comprises at least a first and a second inlet orifices, at least two first outlet orifices, a second outlet orifice and a third outlet orifice, and the rotor interconnection paths are arranged to: in at least one rotary position connect the first inlet orifice to the second outlet orifice and the second inlet orifice to the third outlet orifice, and in at least two other rotary positions connect the first inlet orifice with any one of the first outlet orifices at the same time as the second inlet orifice is connected to the second outlet orifice.

A method and a rotary valve in a continuous chromatography system. The rotary valve comprises a stator with an inner stator face, and a rotor with an inner rotor face arranged in sealing contact with the inner stator face. The stator comprises at least a first and a second inlet orifices, at least two first outlet orifices, a second outlet orifice and a third outlet orifice, and the rotor interconnection paths are arranged to: in at least one rotary position connect the first inlet orifice to the second outlet orifice and the second inlet orifice to the third outlet orifice, and in at least two other rotary positions connect the first inlet orifice with any one of the first outlet orifices at the same time as the second inlet orifice is connected to the second outlet orifice.

Embodiments of multi-column gas chromatography for analysis of a formation sample are disclosed. In one embodiment, an apparatus comprises a gas chromatography instrument and a controller. The gas chromatography instrument comprises a sample injector; a primary column to separate out a hydrocarbon subset; a secondary column valve coupled to the primary column; a primary detector configured to analyze the hydrocarbons of the subset; a heart cutting unit coupled to the secondary column valve and configured to cut, from the subset, at least one isomer having a weight greater than a threshold; a secondary column coupled to an output of the heart cutting unit configured to separate out the at least one isomer; and a secondary detector configured to analyze the at least one isomer. The controller controls the secondary column valve to output the hydrocarbons to the heart cutting unit in response to at least one trigger event.

A preparative liquid chromatograph comprises a separation column, a detector for detecting sample components in an eluate from the separation column, a component trapping unit for introducing the eluate into any of a plurality of trap columns to trap the components, a recovery unit for recovering the eluate into a container, a flow path switching unit for switching a flow path to introduce the eluate to either the component trapping unit or the recovery unit, and a control unit for controlling the flow path switching unit to introduce the eluate into the component trapping unit until the number of components sequentially detected with a single sample introduction into the separation column becomes equal to the number of trap columns, and to introduce the eluate into the recovery unit after the number of the components has exceeded the number of trap columns.

A preparative liquid chromatograph comprises a separation column, a detector for detecting sample components in an eluate from the separation column, a component trapping unit for introducing the eluate into any of a plurality of trap columns to trap the components, a recovery unit for recovering the eluate into a container, a flow path switching unit for switching a flow path to introduce the eluate to either the component trapping unit or the recovery unit, and a control unit for controlling the flow path switching unit to introduce the eluate into the component trapping unit until the number of components sequentially detected with a single sample introduction into the separation column becomes equal to the number of trap columns, and to introduce the eluate into the recovery unit after the number of the components has exceeded the number of trap columns.