JPS61250554A - Method and apparatus for analytical diagnosis of gas chromatography - Google Patents

Abstract

PURPOSE:To enable laboratory automation by simply performing quantitative diagnosis within short time exclusive of the subjectivity of an analyser, by providing a specific analytical diagnosis apparatus to a gas chromatograph (GC). CONSTITUTION:After thermostatic analysis or constant temp. analysis was set by a setting means 3, for example, three kinds of n-alkanes are registered by a registering means 4 and a threshold value K is subsequently set by a setting means 6 and the mixture of three kinds of n-alkanes is injected in a specimen introducing part B. GC performs thermostatic or temp. rising analysis by the order of the means 3 and each holding time is measured by a measured means 7 upon the reception of the peak wave form signal of each alkane from a detector D and converted to an adjusted holding time tR by a converting means 8 and, in the case of thermostatic analysis, log tR and 100N (wherein N is the number of C-atoms of each alkane) of each alkane are calculated and the correlation coefficient rho1 of both of them is calculated and, in temp. rising analysis, 100N of each alkane is calculated and the correlation coefficient rho2 of tR and 100N and, subsequently, the value of 1-rho1 (or rho2) does not exceed a predetermined threshold value, analysis is performed and, when exceeds, GC is inspected and adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to a simple method for diagnosing whether a gas chromatograph is operating normally or not, and an analytical diagnostic device for carrying out this method.

(B) Conventional technology Conventionally, it was determined whether a gas chromatograph was operating normally or not by having an expert look at the O madogram obtained from the gas chromatograph, but in this case, the decision was made based on experience and intuition. It was difficult to judge quantitatively because there were many cases.

(c) Purpose of the Invention This invention was made in view of the above circumstances, and provides a simple method for quantitatively diagnosing whether a gas chromatograph is operating normally or not, and an analytical diagnosis for carrying out this method. The aim is to provide equipment.

(D) Structure of the Invention This invention introduces a mixture of at least three types of n-alkane standard samples into the sample introduction section of a gas chromatograph, and (
The above n is determined by ω constant temperature analysis method or (b) temperature programmed analysis method.
- Measure the retention time of each n-alkane, convert the obtained retention time of each n-alkane into an adjusted retention time t1 based on the retention time of air or methane, a) In the case of isothermal analysis, each n-alkane - The logarithm value of 1iltR and the value of 100N (however, N
is the number of carbon atoms in each n-alkane), then the correlation coefficient ρ1 between the two is calculated, and (in the case of b>temperature-rising analysis,
100N value for each n-alkane (where N is each n-alkane
- the number of carbon atoms in the alkane), calculate the correlation coefficient ρ2 between the adjusted retention time tR of each n-alkane and 100N, and then calculate the value of (1-ρ1 (or ρ2)),
If this value does not exceed a predetermined threshold, analysis is performed, and if the value exceeds the threshold, the gas chromatograph is inspected and adjusted.

In the method of this invention, if the gas chromatograph is in normal operating condition, a) log tR during constant temperature analysis;
There is a linear relationship between and 100N, and in +b+ temperature increase analysis, the fact that 臘 and 100N are in a linear relationship is utilized. That is, in case a) 1ot) tR
and 100NSb), calculate the correlation coefficients ρ1 and ρ2 for 臘 and 100N, and further calculate 1-ρ1 and 1
A method of diagnosing a gas chromatograph by calculating -ρ2 and determining whether these values exceed a permissible value (threshold 2K) that does not impair the reliability of the analysis results. be.

Examples of the standard sample n-alkane used in the method of the present invention include methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane, decane, undecane, and tetradecane. At least three types of n-alkanes are selected and used from these n-alkanes, and 1. Preferably, one n-alkane having t8 and two or more n-alkanes having t8 less than or equal to t8 are used.

Further, this invention comprises a data processing device (1) and an alarm device (21), which are electrically connected in sequence to the following analytical and diagnostic device: a gas chromatograph (a), which is directly used in carrying out the above diagnostic method. (3) means for registering at least three types of n-alkanes to be tested and analyzed; (4) means for registering at least three types of n-alkanes for test analysis; 100 N for each n-alkane (N is the means for calculating the number of carbon atoms (means for setting the 5j1 threshold value (6);
Means (7) for measuring each retention time from the peak waveform signal of each n-alkane in the detector, means (8) for converting the retention time into an adjusted retention time (臘), a) Only in the case of isothermal analysis. Means for calculating log tR (9), 10g
The correlation coefficient ρ between tR and 100N or el and 100
means for calculating the correlation coefficient ρ2 with N, means for calculating 1-ρ1 or 1-ρ2 (when 2υ and 1-ρt>K or 1-ρ2>K, an alarm signal is sent to the alarm ( 2), and a gas chromatograph (2) according to the specification of the setting means (3), generates peak waveform signals of at least three types of n-alkanes subjected to a) isothermal analysis or b) temperature-programmed analysis. The measuring means [7] which receives from the detector (D) measures the retention time of each n-alkane from the waveform signal and sends the signal of these retention times to the converting means (8). converts these retention times into adjusted retention times (tR) and sends a signal of this (tR) to the calculation means (9), and the calculation means (9) receives the designation of a) isothermal analysis from the setting means (3). Calculate log tR only when log
The calculation means ω) receives the registration information of each n-alkane from the registration means (4), calculates 100N of each n-alkane, and calculates 100N of each n-alkane. Receiving a signal of 100N from the calculation means (5) which emits a signal, calculates the correlation coefficient ρ1 between log tU and 100N or the correlation coefficient ρ2 between tR and 100N, and sends the signal to the calculation means αυ, Calculation means (11)
calculates (1-ρ1) or (1-ρ2) and converts the signal into
The alarm transmitting means [F] receives a threshold signal from the threshold setting means (6) and sends it to the alarm transmitting means [F] when 1-ρt>K or 1-ρ2>K. The present invention provides a gas chromatograph analysis and diagnosis device that is configured to send an alarm signal to an alarm device (2) to issue an alarm. Examples of the data processing II! device include the C-RaA data processing device manufactured by Shimadzu Corporation. Examples of alarm devices include alarm lamps, alarm buzzers, alarm indicators, and higher-level centralized control computers.

(E) Embodiment The present invention will be explained with reference to FIG. 1, which is a diagram illustrating the configuration of an embodiment of the analytical and diagnostic apparatus of the present invention.

In Fig. 1, the gas chromatograph (■) consists of a carrier gas supply section (Δ), a sample introduction section (B), a separation column section (C), and a detector (D), and the gas chromatograph analysis and diagnosis device consists of this gas chromatograph section (D). The data processing device @ (1) and the alarm device (21) are electrically connected to the
It is composed of.

Furthermore, the data processing device (1) includes: a) means (3) for setting constant temperature analysis or temperature-programmed analysis; means (4) for registering at least three types of n-alkanes;
means (5) for calculating 00N, means (6) for setting the threshold value, and means (711) for measuring each retention time from the peak waveform signal of each n-alkane from the detector (711) adjusting and holding the retention time. Means (8) for converting into time ([1), a
) Means to calculate 10111 Eg only in case of constant temperature analysis (9), correlation coefficient ρ1 between log tR and 100N
Or means η for calculating the correlation coefficient ρ2 between cough and 100N
, 1-ρ1 or 1-ρ2 means 0111 and 1
When -ρt>K or 1-ρ2>K, the alarm signal is transmitted to the alarm (2).

The analysis and diagnosis apparatus described above is operated as follows.

(1) Maintain the gas chromatograph ■ in a steady state before analysis.

(i) Using the setting means (3), set whether a>constant temperature analysis or b) temperature rising analysis.

(To) At least three types of n-
Register Alkane.

(2) The setting means (6) sets the threshold value.

・(V) At least three kinds of n in the sample introduction part (B)
- Injecting the mixture of alkanes.

&D In response to the instruction from the means (3), the gas chromatograph performs a) isothermal analysis or b) temperature-programmed analysis of n-alkanes to detect the peak waveform signal of each n-alkane transmitted from the detector (D). and each retention time is determined by the measuring means (7
) is measured by

The converting means (8) receives the signal of the retention time of each n-alkane from the measuring means (7') and calculates the adjusted retention time (
tR).

a) The calculation means (9) calculates the calculation means (9) from the setting means (3).
Upon receiving the specification of constant temperature analysis or b) temperature rise analysis and receiving the tR signal from the converting means (8), calculate the log tumor only in the case of a).
The signal of tR is sent to the calculation means [F].

O→ Calculation means (5) receives the registration information of each n-alkane from the registration means (4) and calculates 10 of each n-alkane.
0N is calculated, and this 100N signal is sent to the calculation means □□□.

α) The calculation means color calculates the correlation coefficient ρ1 between log tR and 100N or the correlation coefficient ρ2 between tR and 100N, and sends the signal to the calculation means di).

1XiJ calculation means (1υ calculates 1-ρ1 or 1-ρ2 and sends the signal to the next alarm transmission means.

(*ii) The alarm transmitting means [F] receives the 1-ρ or 1-ρ2 signal and the threshold value signal from the specifying means (6), and determines whether 1-ρ1>K or 1-ρ2>. At the time of K, an alarm signal is sent to the alarm device (2) to issue an alarm.

As described above, according to the above-mentioned apparatus, analysis and diagnosis using a gas chromatograph can be carried out simply, quickly, and quantitatively.

(f) Effects of the invention According to this invention, diagnosis using a conventional gas chromatograph can be performed by:
Previously, analytical experts looked at the chromatogram obtained by actually analyzing the sample and determined whether it was normal or not based on their experience. This makes it possible to make a diagnosis, further promoting laboratory automation.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the configuration of an analysis and diagnosis apparatus according to an embodiment of the present invention. (1)...Data processing device, +21...
・Alarm, (3)...a) Isothermal analysis or b) Elevation analysis setting means, (4)...N-alkane registration means, (5)...・100N calculation means, (6
)...... Calculation means for threshold value, (7)...
・Retention time measuring means, (8)... Conversion means to adjusted retention time (j3), (9)...+00
tR calculation means, □□□...Correlation coefficient ρ1 or ρ2 calculation means, (111...1-ρ1 or 1-
ρ2 calculating means, surface... Alarm signal transmitting means, ■... Gas chromatograph, (A)... Carrier gas supply section, (B)...
... Sample introduction section, (C) ... Separation column section,
(D>...Detector.

Claims (1)

[Claims] 1. A mixture of at least three types of n-alkane standard samples is introduced into the sample introduction section of a gas chromatograph, and the n- Measure the retention time of each alkane, convert the obtained retention time of each n-alkane into an adjusted retention time t_R based on the retention time of air or methane, and a) In the case of constant temperature analysis, calculate the retention time of each n-alkane. Calculate the logarithm value of t_R and the value of 100N (where N is the number of carbon atoms of each n-alkane) for the alkane during adjustment and holding, then calculate the correlation coefficient ρ_1 between the two, and (b) In the case of temperature-rise analysis is the value of 100N for each n-alkane (where N is the value of 100N for each n-alkane).
The number of carbon atoms in the alkane) is calculated, the correlation coefficient ρ_2 between the adjusted retention time t_R and 100N for each n-alkane is calculated, and the value of [1-ρ_1 (or ρ_2)) is calculated, and this value is An analytical diagnostic method for gas chromatography that consists of performing an analysis if a predetermined threshold is not exceeded, and inspecting and adjusting the gas chromatograph if the threshold is exceeded. 2. Consisting of a data processing device (1) and an alarm device (2) electrically connected to the gas chromatograph in sequence, the data processing device has a means for setting a) isothermal analysis or b) temperature-programmed analysis (3). ),
Means (4) for registering at least three types of n-alkanes to be tested and analyzed, 100N of each n-alkane (N is n
- a means (5) for calculating the number of carbon atoms in the alkane), a means (6) for setting the threshold value, a means (6) for measuring the retention time of each n-alkane from the peak waveform signal from the detector (
7) Means for converting the holding time into an adjusted holding time (t_R) (8) a) Means for calculating logt_R only in the case of isothermal analysis (9) Correlation coefficient ρ_1 between logt_R and 100N or between t_R and 100N Means (10) for calculating the correlation coefficient ρ_2 of , means (11) for calculating 1-ρ_1 or 1-ρ_2, and 1-ρ_1>K or 1-ρ_2>
In the case of K, the alarm transmitting means D transmits an alarm signal to the alarm device (2), and the gas chromatograph (20) performs a) constant temperature analysis or b) temperature increase according to the specification of the setting means (3). A detector (
The measuring means (7) received from D) measures the retention time of each n-alkane from the waveform signal and sends the signals of these retention times to the converting means (8), which converts these retention times. is converted into adjusted retention time (t_R) and this (t_
R) is sent to the calculation means (9), and the calculation means (9) calculates logt_R only when a) isothermal analysis is specified from the setting means (3), and calculates logt_R.
The signal of R or t_R is sent to the calculation means (10), and the calculation means (10) receives the registration information of each n-alkane from the registration means (4), calculates 100N of each n-alkane, and calculates these 100N. The correlation coefficient ρ_1 between logt_R and 100N or the correlation coefficient ρ_ between t_R and 100N is calculated by receiving the 100N signal from the calculation means (5) which generates the signal.
2 and sends the signal to the calculation means (11), the calculation means (11) calculates (1-ρ_1) or (1-ρ_2) and sets the signal as a threshold value (6). 1-ρ_1>K or 1-ρ_
A gas chromatograph analysis and diagnosis device configured to send an alarm signal to an alarm device (2) to issue an alarm when 2>K.