JP7058017B2 - Flow analysis method, flow analyzer - Google Patents

Description

The present invention relates to a flow analysis method and a flow analyzer.

In the Japanese industrial standard factory effluent test method (see Non-Patent Document 1 below), the pretreatment for analysis of metal elements contained in a sample (water sample) is performed after adding an acid such as nitric acid or hydrochloric acid to the sample. The method of heat treatment is specified. This pretreatment is an operation mainly performed for the purpose of decomposing organic substances and suspensions coexisting in the sample and metal complexes, but it is very time-consuming and prevents acid exposure to the operator during the treatment. Measures need to be taken.

In this regard, if a "flow analysis method" such as a "flow injection analysis method" abbreviated as FIA or a "continuous flow analysis method (Continuous Flow Analysis)" abbreviated as CFA is used, This pretreatment is automated, and it is expected that the processing speed of the sample will be improved and the working environment will be improved.

Japanese Industrial Standards "Factory Wastewater Test Method (JIS K 0102)"

However, in order to perform accurate analysis on a sample containing an organic substance or a poorly soluble metal, it is necessary to secure a long time (heating time) for heat treatment of the sample after acid addition.

Among the above-mentioned flow analysis methods, when the heating time is lengthened in the flow injection analysis method, the flow velocity of the mobile phase is lowered.

However, if the flow velocity of the mobile phase is reduced in the flow injection analysis method, a tailing phenomenon occurs due to the diffusion of the sample introduced into the mobile phase, which adversely affects the measurement data.

On the other hand, in the continuous flow analysis method, since bubble segmentation is performed on the sample introduced into the conduit to create a plurality of segments partitioned by bubbles, diffusion of the sample is unlikely to occur even if the transfer rate of the segments is reduced.

However, as shown in FIGS. 6A and 6B, when the step of heating the segment (S) is executed in the conventional continuous flow analysis method, the bubbles (B) that partition the segment expand, so that the segment (S) expands. The bubble (B) rapidly pushes the segment (S) toward the downstream side of the pipeline 100.

Therefore, with the conventional flow analysis method, it is difficult to accurately perform the analysis requiring heat treatment by simply lowering the flow velocity of the mobile phase.

The present invention has been developed in view of the above technical problems, and an object of the present invention is to provide a novel flow analysis method and a flow analysis apparatus capable of performing sufficient heat treatment on a sample.

The flow analysis method of the present invention for solving the technical problem includes a sample introduction step of introducing a sample into a pipeline, a heating step of heat-treating a sample transferred along the conduit, and a post-heat treatment. It is a flow analysis method that executes an analysis step of quantitatively or qualitatively analyzing a sample, and further executes a pressurizing step of applying a pressure against the flow of the sample transferred along the pipeline. (Hereinafter referred to as "the analysis method of the present invention").

In the analysis method of the present invention, it is a preferable embodiment to apply a pressure against the flow of the sample by introducing compressed air into the conduit when the pressurizing step is executed.

In the analysis method of the present invention, it is a preferable embodiment to perform bubble segmentation on the sample to be introduced at the time of executing the sample introduction step to create a plurality of segments partitioned by bubbles.

In the analysis method of the present invention, it is a preferable embodiment to perform the heat treatment at a heating temperature of 40 ° C. or higher when the heating step is executed.

In the analysis method of the present invention, it is a preferable embodiment that the heat treatment is performed with a heating time of 5 minutes or more for each unit of the introduced sample at the time of executing the heating step.

Further, in the analysis method of the present invention, it is a preferable embodiment to execute a reagent addition step of adding a reagent to the flow of the sample transferred along the pipeline.

The flow analyzer of the present invention for solving the technical problem includes a sampling device for introducing a sample into a pipeline, a heating device for heat-treating a sample transferred along the pipeline, and a post-heat treatment. A flow analyzer comprising an analyzer that performs quantitative analysis or qualitative analysis on the sample of the above, and further, a pressurizing device that applies a pressure against the flow of the sample transferred along the pipeline. (Hereinafter, referred to as "the analyzer of the present invention").

The analyzer of the present invention is provided with a bubble segmenting device that performs bubble segmentation on a sample introduced into the pipeline and creates a plurality of segments partitioned by bubbles in the pipeline. This is a preferred embodiment.

In the analyzer of the present invention, it is preferable that a reagent addition device for adding a reagent to the flow of the sample transferred along the pipeline is further provided.

According to the present invention, a sample transferred along a pipeline can be sufficiently heat-treated.

FIG. 1 is a schematic configuration diagram showing an embodiment of the analyzer of the present invention. FIG. 2 is a schematic configuration diagram of the analyzer of the present invention and an enlarged cross-sectional view showing a portion where a segment is created. FIG. 3 is a schematic configuration diagram of the analyzer of the present invention and an enlarged cross-sectional view showing a portion responsible for the pressurizing step. FIG. 4 is a schematic configuration diagram showing another embodiment of the analyzer of the present invention. FIG. 5 is a schematic configuration diagram showing still another embodiment of the analyzer of the present invention. FIG. 6 is a cross-sectional view (a) showing a segment transferred through a pipeline in a conventional continuous flow analysis method, and a cross-sectional view (b) showing the expansion of bubbles when heat treatment is performed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments.

<Flow analyzer (1)>
FIG. 1 shows an embodiment of the analysis device 1 of the present invention for executing the analysis method of the present invention. The analyzer 1 of the present invention includes a "sampling device (2)", a "bubble segmenting device (3)", a "heating device (4)", an "analyzer (5)", and a "pressurizing device (" 6) ”and.

-Sampling device 2-
The sampling device 2 is responsible for sampling a sample and introducing it into the pipeline 100. In the present embodiment, the sampling device 2 is constructed by a sampling tube 20 that guides a sample to the pipeline 100 and a sampling pump (perista pump) 21 that applies a suction force to the sampling tube 20.

-Bubble segmentation device 3-
The bubble segmentation device 3 plays a role of performing bubble segmentation on the sample sampled by the sampling device 2. In the present embodiment, the bubble segmentation device 3 is constructed by an air introduction pipe 30 that guides air to the pipeline 100 and an air introduction pump (perista pump) 31 that applies suction force to the air introduction pipe 30. ..

-Heating device 4-
The heating device 4 is responsible for heat-treating the sample transferred along the pipeline 100. In the present embodiment, the heating device 4 is constructed by arranging a heater in the middle of the pipeline 100.

-Analyzer 5-
The analyzer 5 is responsible for performing quantitative analysis or qualitative analysis on the heat-treated sample. In this embodiment, an ICP emission spectroscopic analyzer was used as the analyzer 5.

-Pressurizing device 6-
The pressurizing device 6 is responsible for applying pressure against the flow of the sample transferred along the conduit 100. In the present embodiment, the pressurizing device 6 includes a pressurizing pipe 60 connected to the downstream end of the conduit 100, a compressor 61 for introducing compressed air into the conduit 100 through the pressurizing pipe 60, and the pressurizing pipe 60. It was constructed by a valve 62 arranged in the middle of the.

<Analytical Method of the Present Invention (Metal Analytical Method of the Present Invention)>
The analyzer 1 of the present invention having the above configuration is an apparatus for executing the analysis method of the present invention. In this analysis method of the present invention, a "sample introduction step", a "heating step", an "analysis step", and a "pressurization step" are executed.

-Sample introduction process-
In the sample introduction step, the sample is introduced into the conduit 100. In the present embodiment, as shown in FIG. 2, the sample was introduced into the pipeline 100 by the sampling device 2. In introducing the sample into the pipeline 100, the bubble segmentation device 3 was used to segment the bubbles to introduce air, and a plurality of segments (S) partitioned by the bubbles (B) were created.

-Heating process-
In the heating step, a sample (in this embodiment, the segment (S)) transferred along the pipeline 100 is heat-treated. In the present embodiment, the heating step is executed by heating a part of the conduit 100 with the heating device 4 and sequentially passing the sample through the heated conduit 100.

-Analysis process-
In the analysis step, quantitative analysis or qualitative analysis is performed on the sample after heat treatment. In the present embodiment, as shown in FIG. 3, the analysis step is executed by introducing the sample into the analyzer 5 through the analysis tube 50 which branches downward in the downstream of the pipeline 100. In the present embodiment, an analysis pump (perista pump) 51 is arranged in the middle of the analysis tube 50, and the introduction speed of the sample introduced into the analyzer 5 through the analysis tube 50 by the analysis pump 51. It is a mechanism to determine. Further, in the present embodiment, the bubbles (B) that have partitioned the segment (S) are discharged through the degassing tube 70 that branches upward further downstream from the analysis tube 50, and the analysis device 5 The mechanism is such that bubbles (B) do not mix with the sample introduced into. A degassing pump (perista pump) 71 for determining the discharge rate of air bubbles (B) is arranged in the middle of the degassing pipe 70.

-Pressurization process-
In the pressurizing step, a pressure is applied against the flow of the sample transferred along the conduit 100 (see FIG. 3). In the present embodiment, the pressurization is performed by adjusting the opening degree of the valve 62 while driving the compressor 61 constituting the pressurizing device 6 and determining the pressure of the compressed air introduced into the pipeline 100. The process was carried out.

In the analysis method of the present invention according to the present embodiment in which each of the steps is executed, in the sample introduction step, when the sample is introduced into the pipeline 100, the bubble segmentation device 3 performs bubble segmentation to introduce air. This is an analysis method that is a mechanism for creating a plurality of segments (S) partitioned by bubbles (B) (a mechanism similar to the continuous flow analysis method).

Further, in the analysis method of the present invention, since the pressure against the flow of the sample is applied in the pressurizing step, the expansion of the bubbles (B) at the time of executing the heating step is preferably suppressed. As a result, the selection range of the heating temperature and the heating time at the time of executing the heating step is increased, so that high temperature and high pressure conditions can be realized and sufficient heat treatment can be performed.

In the analysis method of the present invention, the heating temperature and the heating time at the time of executing the heating step may be appropriately selected according to the type of sample and the analysis target, and are not particularly limited. However, according to the analysis method of the present invention, it is possible to select a heating temperature and a heating time that could not be executed in the conventional continuous flow analysis method.

Therefore, in the analysis method of the present invention, it is preferable to perform the heat treatment at a heating temperature of 40 ° C. or higher (more preferably 90 ° C. or higher) when the heating step is executed. Further, in the analysis method of the present invention, it is preferable to perform the heat treatment for a heating time of 5 minutes or more (more preferably 30 minutes or more) for each unit of the introduced sample at the time of executing the heating step.

Further, the degree of pressure applied in the pressurizing step may be appropriately determined according to the heating temperature and heating time in the heating step, and is not particularly limited. The pressure applied in the pressurizing step is an arbitrary pressure of 0.14 MPa or less (including a negative pressure of less than 0.1 MPa in some cases, more preferably more than 0.1 MPa and 0.13 MPa or less). Is preferable.

By the way, in the present embodiment, an ICP emission spectroscopic analyzer is used as the analyzer 5 for executing the analysis step, but the analyzer 5 is not particularly limited, and various analyzers are used. (For example, a frame atomic absorption spectrometer, an electrically heated atomic absorption spectrometer, an ICP mass spectrometer, gas chromatography, etc.) can be appropriately selected and used.

Further, in the present embodiment, the pressurizing device 6 employs a mechanism of introducing compressed air into the pipeline 100 by the compressor 61, but the pressurizing device 6 transfers the pressure along the conduit 100. The mechanism is not limited as long as it can apply pressure against the flow of the segment to be formed. For example, as the pressurizing device 6, a device having a mechanism of applying pressure by pressurizing by a piston may be adopted.

Further, in the present embodiment, only the heat treatment is performed as the pretreatment of the sample for executing the analysis step, but the present invention denies that other pretreatments are performed in addition to the heat treatment. is not. For example, as in another aspect of the analyzer 1 of the present invention shown in FIG. 4, a reagent addition device 8 including a reagent introduction tube 80 for introducing a reagent into a pipeline 100 and a reagent introduction pump 81 is used. A mechanism for executing a reagent addition step of adding a reagent to the flow of a sample transferred along the pipeline 100 may be used.

The reagent introduced into the conduit 100 at the time of executing the reagent addition step is appropriately selected according to the necessity of pretreatment of the sample, and is not particularly limited. As the reagent, for example, an acidic reagent such as hydrochloric acid, nitric acid, perchloric acid, sulfuric acid, or a basic reagent such as sodium hydroxide or potassium hydroxide can be appropriately selected and used.

Further, the timing of adding the reagent is not particularly limited, and for example, the reagent may be added before, at the time of execution, or at the time of execution of the heating step.

In addition, in the present embodiment, an analysis method having a mechanism similar to the continuous flow analysis method is constructed, but in the present invention, a segment (S) is always created when the sample is introduced into the conduit 100. I don't need that.

For example, as in still another aspect of the analyzer 1 of the present invention shown in FIG. 5, a mechanism for directly introducing the sample into the conduit 100 (a mechanism according to the flow injection analysis method) may be used.

In this case, since the sample introduced into the pipeline 100 is not partitioned by the bubbles (B), the pressurizing step is not executed in order to suppress the expansion of the bubbles (B) at the time of executing the heating step. Instead, it is performed to accelerate the processing of the sample by the synergistic effect of the heating in the heating step and the pressurization in the pressurizing step by applying a pressure against the flow of the sample.

As a result, the processing of the sample can be promoted without extremely reducing the flow velocity of the mobile phase, and as a result, the tailing phenomenon due to the diffusion of the sample is less likely to occur.

When constructing the analysis method of the present invention (and the analyzer 1 of the present invention) by a mechanism according to the flow injection analysis method, the heating temperature is 40 ° C. or higher (more preferably 90 ° C. or higher) at the time of executing the heating step. It is preferable to carry out the heat treatment, and it is preferable to carry out the heat treatment for a heating time of 5 minutes or more (more preferably 10 to 20 minutes) per unit of the introduced sample at the time of executing the heating step.

The invention described above can be practiced in various other forms without departing from its spirit or key features. Therefore, the above embodiments are merely exemplary in all respects and should not be construed in a limited way. The scope of the present invention is shown by the scope of claims and is not bound by the text of the specification. Further, all modifications and modifications that fall within the equivalent scope of the claims are within the scope of the present invention.

INDUSTRIAL APPLICABILITY The present invention is suitably used as a novel flow-type analysis method and a flow-type analyzer.

1 Analytical apparatus of the present invention (flow analyzer)
2 Sampling device 3 Bubble segmentation device 4 Heating device 5 Analytical device 6 Pressurizing device 8 Reagent addition device 100 Pipeline B Bubble S segment

Claims (8)

The sample introduction process for introducing a sample into the pipeline and
A heating step of heat-treating the sample transferred along the pipeline, and
An analysis process for quantitative or qualitative analysis of the heat-treated sample,
Is a flow analysis method that executes
Further, a flow analysis method comprising performing a pressurizing step of applying a pressure against the flow of a sample transferred along the pipeline by introducing compressed air into the pipeline. In the flow analysis method according to claim 1 ,
A flow analysis method in which bubble segmentation is performed on a sample to be introduced at the time of executing the sample introduction step, and a plurality of segments partitioned by bubbles are created. In the flow analysis method according to claim 2 ,
A flow analysis method in which heat treatment is performed at a heating temperature of 40 ° C. or higher when the heating step is executed. In the flow analysis method according to claim 2 or 3 .
A flow analysis method in which a heat treatment is performed with a heating time of 5 minutes or more for each unit of the introduced sample when the heating step is executed. In the flow analysis method according to any one of claims 1 to 4 ,
Further, a flow analysis method for performing a reagent addition step of adding a reagent to the flow of a sample transferred along the pipeline. A sampling device for introducing the sample into the pipeline,
A heating device that heat-treats the sample transferred along the pipeline,
An analyzer that performs quantitative or qualitative analysis on the heat-treated sample,
It is a flow analyzer equipped with
Further, the flow analyzer is provided with a pressurizing device for applying a pressure against the flow of the sample transferred along the pipeline by introducing compressed air into the pipeline. In the flow analyzer according to claim 6 ,
A flow analyzer provided with a bubble segmenting device that performs bubble segmentation on a sample introduced into the pipeline and creates a plurality of segments partitioned by bubbles in the pipeline. In the flow analyzer according to claim 6 or 7 .
Further, a flow analyzer provided with a reagent addition device for adding a reagent into the flow of a sample transferred along the pipeline.

Images