JPH0527665U - Liquid chromatograph - Google Patents

Abstract

(57) [Summary] (Corrected) [Constitution] Cation exchange column 4 and anion exchange column 5 connected with 6-way valves 3-1 and 3-2 and connected in parallel by 4-way valves 6 and 7. And a liquid feed pump 1, an absorption detector 8, a data processor 9 and an eluent a. Two sample loops 2-1 and 2-2 with one sample injection
To the separation column 4, the sample in the sample loop 2-1 is sent to the separation column 4 for separation / detection, and then the 6-way valve 3-2, 4-way valve 6, 7
Is switched to send the sample in the sample loop 2-2 to the separation column 5, separate and detect it, and perform simultaneous analysis. [Effect] Both a cation and anion can be analyzed simultaneously with one set of device and one sample injection, which enables labor saving of the analysis operation and simplification of the device.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a cation / anion simultaneous analysis liquid chromatograph, and particularly to labor saving of an analysis operation and simplification of an apparatus.

[0002]

[Prior Art]

 Ion chromatography is used for the analysis of cations and anions. When analyzing both positive and negative ions in a sample, two sets of equipment are required for each analysis.

When analyzing both cations and anions with one set of devices, it is necessary to exchange the eluent and the column. When the eluent or separation column is switched with a switching valve and analysis is performed with a multi-column system in which cations and anions are used for analysis, it takes a long time to condition after switching the column, and the apparatus becomes large. Non-suppressor type ion chromatography in which a cation-exchange resin column and an anion-exchange resin column are connected in series and separated with one set of equipment (Kazunori Ohta, Miyuki Mochizuki, Kazuhiko Tanaka: Abstract of the 7th Ion Chromatography Forum) Shu, P24 (1990)) has some problems in resolution (Kazuhiko Tanaka: Bunseki, 1991 No. 5, P332-341).

[0004]

[Problems to be solved by the device]

 If two sets of devices are used for the above-mentioned prior art simultaneous analysis of positive and negative ions, there is a problem that it is expensive.

When performing simultaneous analysis with one set of devices, there is a problem that it takes time and labor to exchange the eluent and the column.

When performing simultaneous analysis in a multi-column system in which an eluent or a separation column is selected by a switching valve, there is a problem that conditioning takes time after switching the column and the equipment becomes large, which causes cost. ..

Separation has some problems in non-suppressor type ion chromatography in which a cation exchange resin column and an anion exchange resin column are connected in series with one set of equipment for separation.

In the present invention, a reagent having absorption at a constant wavelength is used as a leaching solution for each of cations and anions, two 6-way valves are connected as a sample valve, and a switching valve for a column is 4 The purpose of the present invention is to save the analytical operation and simplify the device by simultaneously analyzing positive and negative ions by using the device including two one-way valves connected.

[0009]

[Means for Solving the Problems]

 In order to achieve the above object, a reagent having absorption at a fixed wavelength is used as an eluent for each of cations and anions, two 6-way valves are connected as sample valves, and a 4-way valve is used as a column switching valve. It is intended to provide a liquid chromatograph including two connected ones.

In the present invention, a liquid feed pump, two 6-way valves connected, four 4-way valves connected, a cation exchange resin column, an anion exchange resin column and two wavelengths or variable wavelength A liquid chromatograph composed of a photoabsorption detector, and a reagent that absorbs cations and anions at constant wavelengths are used as eluents.

Samples are injected into two connected 6-way valves and two sample loops are filled with sample at one time. The two separation columns are connected in parallel with two 4-way valves, and the sample in one sample loop is sent to the cation exchange resin column by switching the valves. After cation elution, the other 6-way valve and two 4-way valves are switched, the sample in the other sample loop is sent to the anion exchange column, and cations and anions are analyzed simultaneously by one device. Is.

[0012]

[Action]

 In the device of the present invention, both positive and negative ions can be simultaneously analyzed with one set of devices and with one sample injection. Since there is only one type of eluent, conditioning time can be reduced even if the column is switched.

As a result, the simultaneous analysis of positive and negative ions can be labor-saving and simplified.

[0014]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of the apparatus. A pump for feeding the eluent a, a sample injection valve 3-1, 3-2 for feeding the sample filled in the sample loops 2-1 and 2-2 for measuring the sample to the column, Cation-exchange column 4 for separating ions, anion-exchange column 5, separation columns 4, 5 and 4-way valve 6, 7 for changing the flow path to the detector, dual wavelength for detecting ions Alternatively, it comprises a variable wavelength absorption detector 8 and a data processing device 9 for recording / calculating the signal of the detector 8.

As the eluent a, a reagent having absorption at a fixed wavelength for each of cation and anion, such as copper phthalate, is used.

An example of an operation procedure for analysis by the apparatus of the above embodiment will be shown.

FIG. 2 shows a flow path diagram at the time of analysis.

(1) At the time of sample injection, the 6-way valves 3-1, 3-2 are connected to-,-,-, and the 4-way valves 6, 7 are connected for-,-. In this flow path, the eluent a passes through the 6-way valve 3-1 −, the 6-way valve 3-2 −, the 4-way valve 6 −, the cation exchange column 4, and the absorption detector 8. It flows. Before injecting the sample, the four-way valves 6 and 7 are switched, and the release liquid a is also flown in the anion exchange column 5 in advance. The sample injection is performed from the 6-way valve 3-1, and the sample containing cations and anions is-> of the 6-way valve 3-1 → sample loop 2-1 → →, and the 6-way valve 3-2 → → → As shown in the sample loop 2-2 →→, both of the sample loops 2-1 and 2-2 are filled with the sample by a single sample injection.

(2) Analysis of cations Next, the 6-way valve 3-1 is switched, and the flow path is changed like pump 1 → 6 way valve 3-1 (→→ sample loop 2-1 →→), The sample is sent to the cation exchange column 4, and the cations in the sample are separated and detected. During this time, the flow path of the anion exchange column 5 is closed.

(3) Analysis of anion When the elution of the cation is completed, the detection wavelength is changed to a wavelength at which the anion of the eluent a has absorption, and then the 4-way valve 6 and 7 are switched to a 4-way valve. 6 (→) → cation exchange column → 4 way valve 7 (→) → flow eluent a to the absorption detector 8 and switch 6 way valve 3-2, pump 1 → 6 way valve 3-2 ( →→ Sample loop 2-2 →→) Change the flow path. Match the detection wavelength with the absorption of anions. As a result, the sample in the sample loop 2-2 is sent to the anion exchange column 5, and the anions in the sample are separated and detected. During this time, the flow path of the cation exchange column 4 is closed.

As described above, one kind of eluent can be applied to either a cation / anion separation column by using a reagent having an absorption at a fixed wavelength for each of cations and anions as an eluent. Can also be flowed, and the separation column can be switched by a valve and can be detected by one detector. It is clear from these that labor-saving and simplification of simultaneous analysis of positive and negative ions is possible.

[0023]

[Effect of the device]

 As described above, the present invention uses, as eluents, reagents having absorption at constant wavelengths for cations and anions, respectively, and switches the cation exchange column and anion exchange column with a valve to separate them sequentially. By using only one detector, it is possible to save labor and simplify simultaneous analysis of positive and negative ions.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an apparatus.

FIG. 2 is a channel diagram during analysis.

[Explanation of symbols]

a ... Eluent, 1 ... Liquid feed pump, 2-1 and 2-2 ... Sample loop, 3-1, 3-2 ... 6-way valve, 4 ... Cation exchange column, 5 ... Anion exchange column, 6, 7 ... 4-way valve, 8 ... Dual wavelength or wavelength variable absorption detector, 9 ... Data processing device, 10 ... Syringe for sample injection.

Claims (2)

[Scope of utility model registration request] 1. A method in which a reagent having absorption at a constant wavelength is used as an eluent for each of cations and anions, and a cation exchange column and an anion exchange column are used, and an absorption detector is used as a detector. Characteristic liquid chromatograph. 2. A pump for feeding an eluent, a sample injection valve having two 6-way valves connected thereto, a column switching valve having two 4-way valves connected thereto, and a separation column comprising a cation exchange resin. A liquid chromatograph comprising a packed column, a column packed with an anion exchange resin, and a dual wavelength or variable wavelength absorption detector.