JPH02154150A - Automatic analysis apparatus - Google Patents

Abstract

PURPOSE:To allow the exact gas chromatographic analysis under online control even if a liquid sample has a high viscosity by providing a means for fraction collection of a normal volume of a diluting liquid contg. an internal standard material. CONSTITUTION:A sample fraction collecting means A of the apparatus fraction- collects the normal volume of the liquid sample from a process flow passage. The diluting liquid fraction collecting means B fraction-collects the normal volume of the diluting liquid contg. the internal standard material. A mixing means C dilutes and dissolves the respectively fraction-collected liquid samples to prepare a sample soln. The sample soln. adjusted by a transfer means (selector valve 17 etc.) is then transferred to an injection section 3 of gas chromatograph 1. The injection section 3 injects the transferred sample soln. into the column of the gas chromatograph 1. A cleaning means D cleans the insides of the mixing means C and the injection section 3 after the injection. The respective means are controlled online, by which the sample solns. successively fraction-collected from the process flow passage 16 are continuously analyzed by the gas chromatography 1. Data processing 2 of the results is possible.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an automatic analyzer, specifically an automatic analyzer that can continuously analyze liquid samples such as process liquids using a gas chromatograph under online control. Regarding.

[Prior Art and Problems to be Solved by the Invention] On-line controlled process gas chromatographs usually analyze gas components, and when analyzing liquid components, they are limited to substances with low boiling points. Therefore, there is a drawback that it is difficult to perform direct on-line automatic analysis of substances that have a high viscosity at room temperature, low vapor pressure substances that are difficult to vaporize in the vaporization chamber at low temperatures, or substances that are easily thermally decomposed at high temperatures.

In addition, the absolute calibration curve method is adopted in the analysis using the process gas chromatograph mentioned above, and if all components are to be analyzed, it is necessary to adopt a double column system or a backflush force ram system, so the analytical equipment is It has the disadvantage of being complicated, and since it is necessary to employ a pre-cut column system when analyzing some components, it also has the disadvantage of complicating the analytical device.

Furthermore, since the absolute calibration curve method is used as mentioned above, when using a process gas chromatograph for liquid samples (process liquids), the analysis accuracy is greatly affected by the accuracy of the injection amount, so the analysis accuracy is low. There was a problem.

Therefore, it is an object of the present invention to enable gas chromatographic analysis to be carried out under on-line control, even when the liquid sample (process liquid) is highly viscous, has a low vapor pressure, or is prone to thermal decomposition. The purpose of the present invention is to provide an automatic analysis device having a simple configuration.

[Means for Solving the Problems] As a result of various studies, the present inventors have found that, in addition to cases where the liquid sample is highly viscous, it has a low vapor pressure, and even when it is easy to thermally decompose, It was discovered that dilution enables stable analysis using a process gas chromatograph.

The present invention has been made based on the above findings, and provides the following device.

It is equipped with a data processing section that processes the analysis results by a gas chromatograph and a 1.0 gas chromatograph, and
A sample separation means that separates a specified amount of liquid sample from the process flow path, a dilution liquid separation means that separates a specified amount of diluted liquid containing an internal standard substance, and mixes each separated liquid sample with the diluted liquid.・A mixing means for dissolving and preparing a sample solution, a sample solution transfer means for transferring the prepared sample solution to the injection section of the gas chromatograph, an injection means for injecting the transferred sample solution into the column of the gas chromatograph, and injection It is equipped with a cleaning means for cleaning the inside of the mixing means or the injection part afterward, and each means described in 2 is controlled online to sequentially sample the solution from the process flow path. 1) The solution is continuously collected using the gas chromatograph. An automatic analysis device characterized in that the analysis result is processed by the data processing section.

[Effect]

According to the present invention, by diluting the sample solution, even if the liquid sample is highly viscous, it can be reliably transferred to the injection section of the gas chromatograph, and a predetermined amount of the sample can be injected directly into the column. In addition, even in the case of low vapor pressure, it can be analyzed reliably.Furthermore, it is possible to lower the temperature of the vaporization chamber of the gas chromatograph for analysis, so even thermally decomposable liquid samples can be analyzed in a stable state. It can be analyzed using a highly accurate internal standard method, and there is no residual adhesion in the mixing tank etc. after the liquid sample is injected into the column.1) By washing and removing the liquid sample, it is possible to analyze the next liquid sample. online control'n
Liquid samples can be continuously analyzed under the following conditions, and the resulting data processing can be performed automatically.

〔Example〕

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

FIG. 1 is a schematic configuration diagram showing an outline of an automatic analyzer that is an embodiment of the present invention.

The automatic analyzer of this embodiment includes a gas chromatograph 1 and a data processing device (data processing section) 2 that processes the analysis results obtained by the gas chromatograph 1.

The above-mentioned automatic analyzer includes a sample separation means A that separates a prescribed amount of liquid sample from the process flow path shown in the lower left of the figure.
, a diluent liquid separating means B for separating a specified amount of diluted liquid containing an internal standard substance, and a mixing means for preparing a sample solution by mixing and dissolving each separated liquid sample in the diluting liquid. It is equipped with C.

The automatic analyzer also includes a sample solution transfer means (described later) that transfers the prepared sample solution to the injection section 3 of the gas chromatograph 1, and a column of the gas chromatograph 1 (see Fig. The apparatus includes an automatic injection device (injection means, not shown) for injecting into a liquid (not shown), and a cleaning means for cleaning the inside of the mixing means C to the injection part 3 after injection.

In the automatic analyzer, each of the above means and the gas chromatograph 1 are organically connected via piping (indicated by a solid line in the figure). Then, the automatic analyzer controls each of the above-mentioned means online by a computer (not shown), and continuously analyzes the sample solution sequentially taken from the process flow path using the gas chromatograph 1, and the results are The data processing section 2 is configured to automatically process the data processing section 2.

Next, the automatic analyzer will be described in detail.

The sample separation means A is composed of a measuring tube 4 shown by a thick line in the figure, a rotary valve 5 for switching the flow path, and a waste liquid storage tank 6.

The diluted liquid separation means B includes a measuring tube 7, a rotary valve 5,
It consists of a diluent storage tank 9 for storing a diluent in which a standard substance of a predetermined concentration is dissolved, and a pump 10 for delivering the diluent from the storage tank 9, and the measuring tube 7 is hollow. It has a spherical volume expansion part 7a.

The mixing means C is composed of a hollow spherical mixing tank 11, a rotary valve 12, and a waste liquid storage tank 13, and the cleaning means is configured to adjust the cleaning liquid storage tank 14 and the pressure and flow rate of the pressurized gas introduced into the storage tank 14. It is composed of a solenoid valve 15 for

The sample separation means A and the diluted liquid separation means B described above communicate with each other, and the sample separation means A is connected to the switching valve 1.
6, and by rotating the switching valve 16 clockwise by 90 degrees, it is possible to separate the process liquid (sample liquid) from any one of the four process channels. configured so that it is possible.

Further, the sample separation means A, the mixing means C, and the gas chromatograph I are configured so that any two can communicate with each other via a three-way switching valve 17, and the gas chromatograph 1 and the cleaning means , six-way switching valve 18
It is configured to be able to communicate via.

Further, the switching valve 18 is connected to a vacuum system, the atmosphere, and a solenoid valve 19 for introducing pressurized gas, so that the inside of the apparatus can be communicated with any of the above.

In addition, in the above device, the prepared sample $4 solution is transferred to the mixing tank 11.
The transfer means for transferring the liquid from the injection part 3 to the injection part 3 of the gas chromatograph 1 is a vacuum device that is connected to the switching valve 18 and is capable of reducing the pressure in the piping that communicates the injection part 3 and the switching valve 18 with each other. (not shown). In addition, 20 in the figure is also a pressurized gas introduction valve 141, which also forms a part of the above-mentioned mixing means C.

Next, the effect of this embodiment will be explained as shown in FIG. 1 and FIG. 2(a).
This will be explained with reference to (d).

First, in the state shown in FIG. 1, the sample separation means A sends out the process liquid (liquid sample) in the direction of the arrow from the uppermost process channel in the figure through the switching valve 16, and through the rotary valve 5 to the process liquid. The liquid is allowed to flow through the metering tube 4 and finally flows into the waste liquid storage tank 6.

In this way, by passing a certain amount of the process liquid through the measuring tube 4, the measuring tube 4 can be filled with only the process liquid, and as a result, a predetermined amount of the process liquid can be taken out. achieved.

In addition, in the diluted liquid separation means B, the diluted liquid is sent out in the direction of the measuring tube 7 by the pump 10, and the diluted liquid is circulated as shown by the arrow to fill the measuring tube 7. Also performs fractionation and measurement of a specified amount of diluted solution.

While performing the sampling and measuring operations in the above-mentioned sample fractionating means A and diluted liquid fractionating means B, the interiors of the mixing means C and the injection section 3 are also cleaned.

That is, the solenoid valve 15 is opened, the inside of the cleaning liquid storage tank 14 is pressurized with pressurized gas, and the cleaning liquid is sent out in the direction of the arrow through the switching valve 18 and passed through the inside of the mixing tank 11 from below via the switching valve 17 and the rotary valve 12. , by draining the cleaning liquid into the waste liquid storage tank 13, the mixing tank 11 and the pulp 1
2. Clean the inside of the pipes, etc. In this case, the inside of the column can also be washed by injecting the washing liquid into the column using an automatic injection device while the washing liquid is being sent out.

Next, the switching valve 18 and the rotary valve 2 are rotated 60° and 90° to the right, respectively, as shown in FIG.
), simultaneously open the solenoid valve 19,
The remaining cleaning liquid is force-fed with pressurized gas and discharged into the waste liquid storage tank 13, and the -th cleaning operation is completed.

Next, the rotary valve 12 is brought into a state similar to that shown in FIG.
It is rotated by 0° (not shown), the electromagnetic valve 15 is opened, the cleaning liquid is sent out again, and the inside of the mixing tank 11, valve I2, piping, etc. is cleaned again. Thereafter, the rotary valve 12 is brought into a state similar to that shown in FIG. 2(a), and at the same time the switching valve 1
The filter is further rotated 60° to the right (not shown), and the remaining cleaning liquid is discharged into the waste liquid storage tank 13 in the same manner as described above, completing the second cleaning operation.

As mentioned above, when the process liquid separation/measurement operation, the dilution liquid separation/measurement operation, and the cleaning operation of the inside of the mixing tank 11, etc. are completed, the switching valve 18 is rotated 60 degrees to the right to close the device. The interior of the rotary valve is set to atmospheric pressure, both the rotary valve 5 and the rotary valve 8 are rotated 60° to the right, the rotary valve 12 is brought into the same state as in FIG. 1, and the switching valve 17 is further rotated to and the rotary valve 12 are communicated with each other, and the metering pipe 4,
Figure 2 (b
).

Next, the electromagnetic valve 20 is opened and pressurized gas is introduced to move the sample liquid and diluent that are filled in the measuring tubes 4 and 7, respectively, to the mixing tank 11, and the mixing tank +
Bubbling is continued by flowing gas into the diluent to completely mix and dissolve the sample liquid in the diluent, thereby preparing a sample solution.

In addition, by pushing out the diluent with pressurized gas as described above, the diluent passes through the measuring tube 4, so the inside of the measuring tube 4 and the piping etc. connected thereto are cleaned with the diluent. become.

After completing the preparation of the sample solution as described above, as shown in Fig. 2 (
At the same time as switching the switching valve 17 to the state shown in C), the switching valve 18 is rotated 60 degrees to the right to communicate with the vacuum, the pressure inside the device is reduced, and the sample solution is transferred from the mixing tank 11 to the gas chroma by the suction force. Then, a certain amount of the sample solution is accurately injected into the column using an automatic injection device. Simultaneously with the above injection, analysis operations using a normal gas chromatograph are started.
The analysis results are appropriately processed by a data processing device and output as an external signal to a display (not shown) or the like.

Further, in the step shown in FIG. 2(C) above, the switching valve 16 is rotated 90 degrees to the right to select the process flow path at the lowest position in the figure, which is the next target for analysis, and the process flow in the flow path is selected. The preparative/measuring operations for the sample and the preparative/measuring operations for the diluent are started in the same manner as described above.

After injecting the sample solution into the column, the rotary valve 12
At the same time, the switching valve 17 is set to the state shown in FIG. 2(d), the solenoid valve 20 is opened, pressurized gas is introduced, and the sample #1 molten liquid remaining in the mixing means C is transferred to the waste liquid storage tank. 13, a series of analysis operations for one process liquid is completed. Then, according to the method mentioned above,
The cleaning operation of the mixing means C and the injection section 3 is started, and preparations are made for analyzing the next process liquid (the lowest process gas chromatograph channel in the figure).

By repeating the operations detailed above under online control, the process liquid in each process flow path can be automatically analyzed in sequence and the data processing can be performed continuously.

To explain the automatic analyzer of this embodiment in more detail, there is no limit to the process liquid, but for example, in order to automatically analyze it, it is necessary to analyze similar types of liquid such as feed liquid, distillate liquid, and bottom liquid in the distillation process. Something is desirable.

Further, there is no limit to the number of components, but it is preferably about 6 points, although it depends on the analysis cycle time and the difference in composition components.

Further, it is preferable that the process liquid is liquid at room temperature, but it is also possible to use a process liquid that becomes liquid when heated.

Air, nitrogen, etc. can be used as the pressurized gas introduced from the solenoid valve 15.19 or 20, and the pressure is 0.5
~5 kgG/c4 is preferred.

Each of the aforementioned switching valves and rotary valves can be driven by pneumatic pressure or the like and can be accurately controlled. Furthermore, there are no particular limitations on the materials for forming the pipes, various valves, etc., and preferred examples include corrosion-resistant materials such as stainless steel and fluoroplastics.

Further, as the automatic injection device (injection means) into the column, an injection type automatic injection device driven by pneumatic pressure using an external signal is preferable. As mentioned above, this automatic injection device is configured so that when a part of the sample solution or cleaning solution is automatically injected into the column, it evaporates in the vaporization chamber, is entrained by the carrier gas, and normal gas chromatography analysis begins. That's right.

The metering tubes 7 and 4 can also be made of any material such as stainless steel or fluororesin, and the ratio of the metering tube 7 to the metering tube 4 is 3 to 1000 in terms of capacity, preferably 10 to 200. The capacity of the mixing tank 11 is 1 to 3 times, preferably 1.1 to 2.5 times, the total capacity of the metering tube 7 and the metering tube 4. In addition, as a specific example, the capacity of the measuring tube 4 is 0.2
d to 5 relatives are used, preferably 0.3 to 2d. In addition, by making the measuring tube 7 have a structure having a volume expansion part 7a in the middle, and arranging the expansion part 7a vertically (although shown in a horizontal state in the figure), the diluent can flow into the measuring tube 7.
It also has the advantage of preventing it from remaining in the water.

As the diluent, any solvent that dilutes a commonly used process liquid can be used without any restriction. Specific examples of diluent include acetone, methanol, ethanol, butanol,
Methyl acetate, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl butyl ketone, inbutanol, propyl acetate, isobutyl acetate, trichlorethylene, tetrachloroethylene, hexane, cyclobencune, cyclohexane, cyclobutane,
Benzene, toluene, ethylhenzene, orthoxylene, methylstyrene, methylcellosolve, ethylcellosolve, butylcellosolve, methylcellosolve acetate,
Ethyl cellosolve acetate is mentioned. The purity of these diluted liquids is preferably 98% or higher, and they are used alone or in combination.

By using the above diluent, it is possible to lower the viscosity of the fluid to improve injection accuracy, perform low-temperature evaporation in the vaporization chamber of a gas chromatograph, and perform low-temperature evaporation of substances that thermally decompose at high temperatures, resulting in stable analysis. achieved.

Substances commonly used in gas chromatography analysis can be used as internal standard substances, but they must be dissolved in the diluent used, and the composition of the target to be analyzed and the composition of the diluent must be at a position that does not overlap with the detection position on the gas chromatogram. is necessary. This position is determined by performing gas chromatography analysis in advance. Specifically, the internal standard material is
It is determined by considering the process liquid to be analyzed and the diluent used, and the simplest example is when the diluent serves as an internal standard substance and is used as the diluent.

A diluent containing an internal standard substance is a diluent containing a specified amount of the internal standard substance. The specified amount of this internal standard substance is relatively determined by the composition of the process liquid. Therefore, it is preferable to use a diluent containing an internal standard substance that can be used to analyze various process liquids. That is,
When analyzing organic substances contained in a process liquid, it is better to be able to analyze process liquids containing organic substances of the same series.

There are no particular restrictions on the cleaning solution as long as it can clean and remove the residual liquid in mixing tank II, etc., and it may be the same type of solvent as the diluent (not containing an internal standard substance) or a different one. You can leave it there.

In addition, the automatic analyzer of this embodiment automatically repeats cleaning of the mixing tank 11 and the inside of the piping, separation and measurement of liquid samples, injection of sample solutions into columns, processing of analysis results, etc. In order to make this possible, a so-called sequence program is set in advance to operate each means according to the order of instructions given by external signals, and a series of analysis operations including processing of analysis data by gas chromatograph is automatically repeated. It is configured so that it can be done.

As detailed above, in the present invention, the viscosity of the process liquid is reduced by accurately measuring the process liquid and the diluent containing the internal standard substance in the measuring section and mixing them in the mixing tank.
Improves the injection precision of automatic liquid injection equipment for gas chroma l-graphs, and enables analysis of substances with low vapor pressure.
Furthermore, since the temperature of the vaporization chamber of the gas chromatograph can be lowered, it is also possible to analyze substances that are easily decomposed by heat.

In addition, since cleaning is performed every time - analysis operations are completed,
This makes it possible to improve the precision of repeated analyzes and eliminates the need for re-analysis to confirm quality assurance. Furthermore, it is suitable for automatic analysis of organic substances such as liquids with high boiling points (low vapor pressure), liquids with high viscosity at room temperature, and liquids that are unstable and easily decomposed at high temperatures. It can be widely used.

(Experimental Example) A case in which an automatic analyzer having a configuration similar to that shown in FIG. 1 is applied to a purification process of 11-cyanoundecanoic acid will be specifically described.

In the purification of II-cyanoundecanoic acid, a first stage crystallization is performed to remove impurities, and a second stage crystallization is performed to supply 11-cyanoundecanoic acid as a raw material for the subsequent process. There is. In both of these first and second stage crystallization processes, it is necessary to continuously monitor the components contained in the liquid in order to control the quality such as the amount of impurities or the purity of the target product. be.

Therefore, the liquids in both of the above steps are used as process liquids (liquid samples) flowing through two process channels, and the liquids can be analyzed alternately with a gas chromatograph. In addition, the remaining two process flow paths, one for calibration curve verification,
The other one was left as a spare.

In addition, as for the specific configuration of the automatic analyzer, the measuring tube 4 consists of a 0.3 ml loop tube, and the measuring tube 7 consists of a loop tube with a glass hollow sphere connected in the middle, and the capacity is 15 ml. It's a wild goose. In addition, the capacity of the mixing tank 11 is 35 m
It is 1.

The diluent storage tank 9 contains 100% palmitic acid as an internal standard substance. 99% of 20ffi dissolved OOg
Pump 10 that stores butanol and delivers this diluted solution
A tube pump with a delivery capacity of 20 ml/+sin was used.

Air of 5 kgG/ci was used as the pressurized gas for sending and mixing the diluted liquid and liquid sample to the mixing tank 11.

In addition, the gas chromatograph 1 has a vaporization chamber and column temperature of 230°C, and a hydrogen flame ionization detector (F
ID). Flow rate of 60m as carrier gas
1/win nitrogen was used, and formic acid was entrained in the nitrogen to prevent adsorption to the filler. And, as an automatic analyzer, the capacity is 2μ! A piston injection type was used.

Furthermore, 20 f of methanol with a purity of 99% is stored in the cleaning liquid storage tank 14, and the capacity of the waste liquid storage tank 13 in the mixing means C is 8ON.

Using the automatic analyzer described above, the operation of alternately analyzing the liquid in the first and second crystallization steps is carried out according to the flow shown in FIGS. 1 and 2 (a) to (d). , was executed 48 times a day.

Even after continuing the above analysis operation for 30 days, the analysis accuracy remains ±1%.
It was within

Although the present invention has been specifically explained above, the automatic analyzer of the present invention is not limited to that shown in the above embodiments, and can be modified in various ways without departing from the gist.

For example, in the embodiment, a device having four process channels is shown, but the present invention is not limited to this, and the number of process channels can be changed arbitrarily.

In addition, although the case where the diluent containing one volume of the standard substance at a specified concentration is stored in the diluent storage tank is shown, there is also a supply at a predetermined position that can supply a certain amount of the standard substance into the diluent. Means may also be provided.

Furthermore, in the explanation of the operation of the automatic analyzer, the mixing tank 11
In order to remove the cleaning liquid remaining in the solenoid valve 2, etc., a method was shown in which the solenoid valve 19 was opened and pressurized gas was introduced.
0 may be opened and pressurized gas may be introduced.

〔Effect of the invention〕

The automatic analyzer of the present invention can perform continuous gas chromatography analysis reliably and accurately under online control even when liquid samples have high viscosity, low vapor pressure, or are easily thermally decomposed. Moreover, the analysis results can be processed automatically.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an automatic analyzer according to an embodiment of the present invention, and FIGS. 2(a) to 2(d) are operation process diagrams illustrating the outline of the operation of the automatic analyzer. A... Sample separation means B... Diluted liquid separation means C... Mixing means D. 1... Gas chromatograph 2... Data processing device 3... 4.7... Measuring tube 11・・Cleaning means/injection part mixing tank (d)

Claims (1)

[Claims] It is equipped with a gas chromatograph and a data processing unit that processes the analysis results obtained by the gas chromatograph, and also includes a sample separation means for separating a specified amount of liquid sample from the process flow path, and a specified amount of diluent containing an internal standard substance. a diluted liquid separating means for separating the liquid sample, a mixing means for preparing a sample solution by mixing and dissolving each separated liquid sample in a diluting liquid, and a sample solution separating means for transferring the prepared sample solution to the injection part of the gas chromatograph. A transfer means, an injection means for injecting the transferred sample solution into a column of a gas chromatograph, and a cleaning means for cleaning the inside of the mixing means or injection part after injection, and each of the above means is controlled online, An automatic analyzer characterized in that a sample solution taken sequentially from a process flow path is continuously analyzed by the gas chromatograph described above, and the results are processed by the data processing section.