US 4,732,686 A · Weak eluant ion chromatography

Abstract

Apparatus and method for the chromatographic separation and analysis of ionic species. This process is carried out utilizing, in an ion separator column, the combination of a low capacity, high performance resin as the stationary phase, and a weakly ionized electrolyte as the eluant or developing reagent, to effect resolution of ionic species in solution. For anion separation, a weak base resin of low capacity and high efficiency is used as the stationary phase, and a solution of a weak base or water as the mobile phase. For cation separation, a weak acid resin of low capacity and high efficiency is used as the stationary phase and a solution of a weak acid as the mobile phase. Because the eluant employed has a very low background conductivity, it will register only insignificantly on the readout from the conductivity cell. Thus, the method of the invention obviates the need for the eluant suppressor or "stripper" device used in conventional ion chromatography. The invention thereby enables continuous, uninterrupted measurements and eliminates the reservoirs, pumps, complex valving and electronics associated with such suppressor columns.

Claims6

Dependent claims

A method for eliminating the need for an eluant suppressor device in the chromatographic separation and detection of ionic species present in solution, each of the species being of the same valence sign,

said method comprising:
supporting in a column for ion separation, a resin bed including chromatographic resin comprising a low capacity, high-performance stationary phase for controlled interaction with ionic species to be introduced into the column,
introducing into the column a solution containing ionic species to be separated and analyzed,
introducing into the column a solution of developing reagent of weakly ionized electrolytes selected from the group consisting of water, pyridine, H.sub.2 CO.sub.3, and mixtures thereof for eluting ionic species present in the column,
regulating solution flow through the column and passing the solution containing the ionic species and the solution of the developing reagent through the column and through the resin contained therein,
eluting the ionic species with the solution and effecting a resolution of and chromatographic separation of the ionic species as the species traverse a flow path through the column,
sensing and detecting ionic species passing through the resin bed and delivered from the column,
providing visually perceptable indicia correlated with specific ionic species emanating with an effluent solution discharged from the column, and
identifying ionic species in the effluent solution discharged from the column.

6 more elements

Dependencies are inferred from the claim text.

Weak eluant ion chromatography

Life of this patent

Weak eluant ion chromatography

Life of this patent

Abstract

Claims6