JPS5965761A - Measurement method for concentration of liquid - Google Patents

Abstract

PURPOSE:To determine quantitatively the component for which an adequate coloring reagent is not available by using a column packed therein with a solid material in a flow injection mechanism. CONSTITUTION:A sample is circulated through a liquid feed tube 1, a pump 2, a six-way selector valve 3, a specified amt. measuring and dispensing pipe 4, and a liquid feed tube 5. On the other hand, a carrier liquid is discharged after it is passed through a liquid storage tank 6, a pump 7, the valve 3, a column 8 packed therein with a solid material soluble in a free nitric acid and insoluble in the carrier liquid and a detection part 9. When the valve 3 is changed over from this state, the sample circulates without passing the pipe 4 and the carrier flows to the column 8 and the part 9 through the pipe 4. The sample is pushed out by the carrier liquid and dissolves the solid material in the column 8. Since the dissolved material flows into the colorimetric cell in the part 9 and exhibits the absorption peak corresponding to the rate of dissolution, the same is compared with a calibration line and the quantative measurement is thus accomplished.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] This invention involves passing a sample through a column filled with solids that are dissolved by specific components contained in the sample, and determining the amount of solid components contained in the effluent. The present invention relates to a liquid concentration measuring device that locates a specific component in a sample by measuring the amount dissolved.

[Prior art and its problems]

In recent years, flow injection methods have been widely used to speed up routine analysis.

In flow injection, the flow rate of the sample is generally
The target component is quantified by injecting a coloring reagent or precipitant into the solution state into the flow chamber, and detecting it with a detector installed later in the flow, such as a colorimetric device. However, if a suitable coloring reagent is not available, In some cases, complicated pretreatment is required for color development. For example, when quantifying free nitric acid in a sample, there is a problem in that the coloring reagent is oxidized by high concentration of nitric acid and the color fades.

[Purpose of the invention]

The purpose of the present invention is to solve the above-mentioned problems of the prior art, and to quantify components for which a suitable coloring reagent cannot be obtained by using a solid-filled column instead of adding a reagent solution in a flow injection mechanism. It is an object of the present invention to provide a liquid concentration measuring device which uses the amount of dissolved solid in an adult body as an index and can perform the following.

[Summary of invention]

The device according to the present invention includes a liquid feeding mechanism using a pump or compressed air, a flow path switching mechanism using a solenoid valve or a sliding valve, a solid-filled column, a colorimeter, an ion-selective electrode, etc. Mechanism for measuring the degree of dissolution of solids,
It is composed of a liquid-feeding tube that connects these. A sample is intermittently introduced into the column by injecting a fixed amount into a carrier liquid that does not dissolve the solids packed in the column or dissolves only a small amount, and dissolves the solids in the column. In this way, a solution of the solid in the column is intermittently formed in the flow of the carrier liquid, and by recording the dissolved concentration, it is possible to determine the concentration of the target component.

〔Effect of the invention〕

By using the apparatus according to the present invention, it is possible to measure the amount of a component that is reactive with a solid component contained in a sample, or the mixing ratio of a bath liquid consisting of two components, a poor solvent and a rich solvent, with respect to the solid component. is possible. Particularly, in the absence of a general coloring reagent, colorimetric determination can be performed by dissolving a colored solid, which is a more effective measurement method than the method of adding a solution of a coloring reagent.

[Embodiments of the invention]

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows an apparatus for measuring the concentration of free nitric acid as an embodiment of the present invention. The sample is passed from an external piping or liquid tank (not shown) through a liquid supply pipe 1 and a liquid supply pump 2, and then
The carrier liquid, for example, pure water, is released from the storage tank 6 via the six-way switching device 3 by the liquid sending pump 7. Column 8 containing a solid soluble in nitrate, acid and insoluble in the carrier liquid, such as powder or particles of cupric oxide, and a detection section 9
The fluid is drained through. In this case, the detector 9 is suitably a colorimeter capable of detecting the amount of dissolved copper ions, and continuously measures the absorbance in accordance with the absorption peak of copper ions. When the flow path of the six-way switching device 3 is switched from this state, the sample circulates without passing through the quantitative separation tube 4, and the carrier liquid flows to the column 8 and the detection section 9 via the quantitative separation tube 4. . At this time, the sample filled in the quantitative separation tube 4 is pushed out by the carrier liquid, dissolves cupric oxide in the column 8, and enters γAi into the colorimetric cell of the detection section 9, according to the dissolved amount. shows the absorption peak.

If a calibration curve is created using a standard sample using this device, it is possible to perform quantitative determination by comparing it with this curve.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of an apparatus for measuring free nitric acid concentration according to the present invention. 1...Liquid feeding Chicove, 2...Liquid feeding pump, 3...
6-way switch, 4...quantitative fractionation tube, 5...liquid delivery channel
6...Liquid storage tank, 7...Liquid pump, 8...Column, 9...Detection section.

Claims (1)

[Claims] A column filled with a solid whose dissolved amount or dissolution rate varies depending on the concentration of a specific component in the sample, a quantitative injection mechanism for the sample, a mechanism for measuring the dissolved concentration of the solid, and a carrier liquid that does not dissolve the solid or has a small amount of dissolved solid. 1. A liquid concentration measuring device comprising a liquid feeding mechanism for flowing the liquid and configured to determine the concentration of a specific component in a sample from the amount of solid dissolved in the liquid.