Apparatus for the control of chromatographic analysis

摘要

1,000,725. Chromatography apparatus ; control valves. TECHNICON CHROMATOGRAPHY CORPORATION. June 22, 1962 [July 13, 1961], No 24150/62. Heading B1X. In the analysis of a liquid mixture by means of a chromatographic adsorption column and a measuring instrument, e.g. a flow-type colorimeter and a recorder, the apparatus is provided with a two-way rotary valve 12 for turning-on and shutting-off the flow of eluent to the column, a three-way rotary valve 14 for permitting the flow to the measuring instrument of either the eluate from the column or a standardization liquid containing a known constituent of known concentration, and coupling- means connecting the rotary plugs 15, 151 of the two valves whereby the eluate analysing operation is periodically interrupted in order to introduce the standardization liquid for a check of the measuring instrument. Figs. 9 and 10 show the standardization and analysing positions, respectively, of the valves. Conduit 58 of valve 12 is connected to the eluent-source, and conduit 62 leads to the top of the chromatography column. On valve 14, conduit 72 is joined to the outlet of the column, conduit 76 leads to the measuring instrument, and conduit 68 is connected to the source of the standardization liquid. The tap handles 30 of valves 12 and 14 are connected via two rotary solenoids 18 and 20, and a mechanical coupling 16. Electric current is supplied to the solenoids, via microswitches 22, 24, from a control circuit which includes timing devices. When solenoid 18 is energized, the plugs 15, 151 of the valves are rotated through 90 degrees in one direction, whereas when solenoid 20 is energized, the plugs are rotated through 90 degrees in the opposite direction. The timing circuit ensures that the standardization checks on the measuring instrument take place when the eluate from the column does not contain appreciable quantities of the constituent being analysed, i.e. that a check does not occur at a time during the elution of the bulk of a constituent from the column. The analysis of an amino acid mixture, using ninhydrin as colour-reagent, is referred to.