GB786896A - Process for the continuous chromatographic separation of mixtures - Google Patents

Abstract

<PICT:0786896/IV (b)/1> A galactose-xylose-rhamnose mixture dissolved in a butanol-ethanol-water solution is chromatographically separated by applying it by means of micro-injector F to a rotating cylinder A of filter paper through which percolates a quantity of the same solvent drawn by capillarity from vessel B into which tongues of the filter paper dip. The sugars separate on the filter paper after the manner indicated by the shading a-d and separate solutions thereof are collected in the ring of vessels E. The atmosphere is saturated with the solvent. In a generally similar apparatus in which the filter paper is replaced by a ring of ion exchange columns or an annular bed of ion exchanger, a solution, e.g. of sodium acetate and calcium acetate in 0.05 N-acetic acid may be separated into its components, the eluting liquid being the same as the solvent.ALSO:<PICT:0786896/III/1> <PICT:0786896/III/2> A mixture of two or more components is continuously separated chromatographically by applying it to a separating medium so that a uniform relative movement occurs between the point of application and the separating medium, the horizontal component of the velocity of the point of application or the separating medium being uniform, an eluting agent is passed continuously under gravity through said medium and the separated components are continuously collected. The process is said to be applicable to chromatographic adsorption (on a solid phase such as aluminium oxide), chromatographic ion exchange (on e.g. a synthetic resin ion exchanger) and distribution chromatography (between two liquid phases or a liquid and a gas phase, or paper chromatography). In the embodiment shown in Fig. 1, a solution of mixed sugars (see Group IV (b)) is passed through a stationary micro-injector F on to a rotating cylinder of the separating medium, in this case a filter paper A. Eluting medium is drawn by capillarity from vessel B into which tongues formed in the upper edge of the filter paper dip, and percolates through said filter paper causing separation of the components of the mixture due to their selective adsorption on the filter paper. The lower edge of the filter paper is serrated and the percolating liquid drips into a ring of vessels E. The shading a, b, c, d indicates the positions of the various components. Fig. 2 indicates a generally similar arrangement in which the separating medium is an ion exchange resin contained in columns arranged in a ring, and an eluting medium is supplied to each. The separate columns could be replaced by a continuous bed of annular form. In a modification of the above types of apparatus, the separating medium may remain stationary whilst the means for applying the mixture and the collecting vessels rotate. Ancillary apparatus for measuring or registering the refractive index, conductivity, dielectric constant or pH of the liquid draining from the apparatus may be provided.