JPH08301793A - Reaction control with near-infrared rays - Google Patents

Abstract

PURPOSE: To enable prompt reflection of the composition change in the reaction mixture on the reactor operations by promptly conducting the on-line component analysis of the reaction mixture. CONSTITUTION: The reaction mixture at the outlet of the reactor is component- analyzed through the near-infrared absorption spectroscopy and the feed rate of the feedstock or the proportions of one or two or more of the components in the feedstock are changed on the basis of the analytical results to keep the composition of the reaction mixture constant at the outlet of the reactor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a reactor which is a typical device in the chemical industry.

[0002]

2. Description of the Related Art In the conventional operation management of a reactor, the composition of the reactor outlet was analyzed as necessary or at any time in order to maintain a desired liquid composition of the reactant at the reactor outlet.
However, this causes a large time delay and an increase in the amount of work because the sample is taken directly from the device for analysis. When the time delay occurs, production continues, so if the measurement result is out of specification, product loss occurs, and if the out-of-specification reaction solution is sent to the purification process, the operating conditions of the distillation column are constant. Otherwise, in some cases the plant becomes unstable and it becomes impossible to continue operation. As a method of eliminating the time delay, the temperature inside the reactor is conveniently monitored and used as a guideline for changes in the reaction state, which is used as a guideline for operation control. Driving cannot be achieved.

Incidentally, the high level operation referred to here is
The difference between the composition of the reaction solution as the control target and the actual composition is almost eliminated, and the operation of the distillation column is stabilized in the subsequent purification step. As a means of eliminating the time delay, in recent years, an online analytical instrument has been introduced into the distillation column to minimize the time delay of the analysis so that the person can judge from the analysis value or the device can automatically judge and control. Has been

However, these on-line analytical instruments are characterized by the fact that the sampling of the usual gas chromatography analysis is performed automatically, and the time for the instrument to analyze is not shortened at all, and a more rapid on-line real-time analytical method. Was requested. On the other hand, near-infrared analysis is known as a new method for online real-time analysis in recent years. This analytical method was originally used for measuring proteins such as cereals, but has recently been used for a method for optimizing or automating the operation of a petrochemical plant and has begun to attract attention.

For example, as disclosed in Japanese Unexamined Patent Publication No. 2-28293, by analyzing the hydrocarbons supplied to the cracking furnace by using an infrared analysis photometer,
A method of controlling the yield of (di) olefins such as ethylene, propylene, etc. as a function of the analysis is disclosed. This technology analyzes the supplied hydrocarbons online and measures the analytical values in real time. The feature is that the composition of the feed liquid is analyzed and the reaction conditions are controlled.

However, it is difficult to control the composition at the outlet of the reactor accurately to the target value even if the reaction conditions are changed from the analytical value of the composition of the feed liquid similarly in the control of the general synthesis reaction. In addition, there was a great demand for a new control method because the concentration of the part to be controlled varies greatly.

[0007]

The object of the present invention is to control the reactor by performing composition analysis of the reaction solution of the reactor without lag, for example, synthesizing ethylbenzene by synthesizing benzene and ethylene. It is meant to provide a way to do.

[0008]

As a result of intensive studies, the present inventor found that composition analysis is possible by directly transmitting near-infrared rays to the reaction solution at the outlet of the reactor and measuring the absorption spectrum thereof. Furthermore, they have found that the operation management of the reactor can be performed with high accuracy without time delay, and the present invention has been completed based on this finding.

That is, the present invention relates to a method for controlling the operation of a reactor for synthesizing a reaction product, in which the composition of the reaction product at the outlet of the reactor is analyzed by near-infrared spectrum, and the measured value obtained is used for the reaction. Is a reaction control method using near-infrared radiation, characterized in that the composition or composition of the reactant at the outlet of the reactor is made constant by changing the amount or ratio of the raw material supplied to

In the present invention, near infrared light means visible light (400 to 7
00 nm) and mid-infrared rays (2,500-10000 nm)
It is light with a wavelength in the middle of. As a characteristic of near-infrared light, the spectrum of wavelengths in this range is remarkably smaller than the number of peaks of the spectrum in the mid-infrared region because absorption occurs due to overtones of absorption and coupling vibrations occurring in the mid-infrared region.

The change in absorbance with respect to the unit concentration change in the absorption spectrum of near infrared rays is 1/10 to 1/1000 as compared with that of mid infrared rays. The analysis principle will be described below by taking the absorption spectrum of near infrared rays as an example, but the basic principle is the same for the reflection spectrum, the internal scattering spectrum and the transmission spectrum. The substance to be measured is irradiated with light in a predetermined wavelength range of near infrared rays, the absorbance is measured, and a calibration curve is obtained from the relationship between the concentration and the absorbance. Further, in many cases, the continuous absorption spectrum is subjected to the second-order differential conversion with respect to the wavelength, so that the characteristics of each spectrum are emphasized, which enables analysis with higher accuracy.

In the first derivative or second derivative of the pure substance spectrum of the component of interest to be analyzed, the peak unique to that component is called the attribution wavelength, and a calibration curve is prepared at this wavelength. When there is no attribution wavelength, multivariate regression using several hundred wavelengths is used. There are generally three methods for obtaining a spectrum that collects near-infrared rays from a sample. That is, there are a reflection method of irradiating light on a substance to be measured and collecting its reflected light, a transmission method of collecting transmitted light of a sample, and a combined method of transmission and internal scattering. The transmission method can be widely applied to a film having a high transparency and a solution having a high degree of scattering, or a paste, a slurry or a suspension. The combined method of transmission and internal scattering gives clear spectra for liquid, suspension or gel-like substances with clear and little scattering.
The reflection method that detects reflected light is most suitable for opaque powder, high-concentration substances, and movable solids.

In the case of the reflection method, the light from the light source is first passed through the diffraction grating to disperse it, and then its energy is sent to the sample. For each scan, the energy reflected from the sample is collected and detected by the probe, and the data is sent to the instrument. In the transmission method and the combined method of transmission and internal scattering, the reference spectrum for reference is subtracted from the sample spectrum in which the sample is transmitted, and the spectrum after the calculation is introduced into the diffraction grating to perform spectrum dispersion and detection.

In near infrared analysis, multiple components can be measured simultaneously and at high speed in about one minute. It is possible for the operator to monitor the analysis result and reflect it manually in the operation, but not only that, the analyzer can be directly connected to the controller and the analysis result can be automatically reflected in the control of the reactor. It is possible. Here, control means changing one or more reaction conditions in the feed amount of the raw material to the reactor or the ratio of the raw material supplied to the reactor (for example, the ratio of the ethyl group and the benzene ring). Means that the composition of the reactant at the outlet of the reactor is kept constant. That is, the operator can control by looking at the analysis result and changing the feed amount of the raw material to the reactor or the ratio of the ethyl group and the benzene ring of the raw material supplied to the reactor. The reaction conditions to be changed include not only the amount and ratio of raw materials supplied to the reactor, but also the amount of catalyst supplied to the reactor, the reaction temperature, the reaction pressure, and the like.

The reaction pressure of the reaction used in the present invention is not particularly limited, and any of reduced pressure reaction, pressurized reaction, and normal pressure reaction will limit the present invention. is not. As a control method of the present invention, for example,
In the process for producing ethylbenzene, what is supplied to the reactor is ethylene, benzene, and polyethylbenzeneethylene in which 2 to 6 ethyl groups are added to the benzene ring recycled from the purification system. The reaction product of the reaction is a substance having a high boiling point such as unreacted benzene with benzene, polyethylbenzene having 1 to 6 ethyl groups added to the benzene ring, diphenylethane, and ethyldiphenylethane.

Generally, these mixtures are separated in the following distillation column. In the first benzene column, benzene is separated from the top, ethylbenzene, polyethylbenzene, and substances having a boiling point higher than those of polyethylbenzene are separated from the bottom, and the second ethylbenzene column is separated. Ethylbenzene is separated from the top of the column, polyethylbenzene is separated from the bottom of the column, and a substance having a boiling point higher than that of polyethylbenzene is separated. In the third polyethylbenzene column, polyethylbenzene is separated from the top of the column and a substance having a boiling point higher than that of polyethylbenzene is separated from the bottom of the column.

The type of catalyst used in the alkylation reaction of ethylene and benzene is such that the main catalyst is a mixture of aluminum chloride cocatalyst and hydrochloric acid and is continuously fed to the reactor, or a fixed bed zeolite catalyst or a fluidized bed zeolite catalyst. Etc. are common. The reaction form is not limited to the present invention and may be either a gas phase reaction or a liquid phase reaction. The measurement target of the above analysis can be composition analysis of the overhead gas before the condensation or the overhead liquid after the condensation, but the liquid has higher near-infrared spectrum sensitivity and higher analysis accuracy. Furthermore, the liquid state generally has a lower measurement temperature, is less severe for the measuring instrument, and is more likely to fall within the desirable measurement temperature range shown below.

Further, the temperature and pressure of the hydrocarbon to be measured do not limit the composition analysis of the present invention at all, and are not affected by the chemical characteristics of the hydrocarbon at all, but -10 ° C to 3 ° C.
It is desirable that the substance to be measured be maintained within the range of 00 ° C and 0 to 70 kg / cm2G, and more desirably 0 ° C to 50
C, 0 to 20 kg / cm ² G. In the temperature range outside of this temperature range and pressure range, the measurement generally becomes difficult due to the problem of the durability of the sealing material for packing used in the probe of the near infrared ray measuring device.

The wavelength range of near infrared rays is 700 nm to 25
Although it is 00 nm, the specific peak of the substance varies depending on the target substance to be measured when the spectrum is taken, and therefore the present invention does not limit the wavelength range of near infrared rays. For example, a pellet of polyethylene or polyvinyl acetate shows a specific peak around 1800 nm to 2200 nm, and a polystyrene shows a specific peak around 1100 nm to 2500 nm. In the reaction product of the alkylation by the reaction of ethylene and benzene, 1100 nm to 2100 nm
A specific peak appears around.

Further, specifically, depending on the substance to be measured,
The following multiple wavelengths are listed. That is, for ethylbenzene, 1614 nm, 2026 nm, 1656n
m, 2070 nm, 1846 for m-diethylbenzene
nm, 1716 nm, 1770 nm, 1644 nm, 1874 nm, 1880 nm for p-diethylbenzene,
1732 nm, 1748 n for o-diethylbenzene
m, 1646 nm, 1986 nm, 2080 nm, 1,
1638nm, 1830n for 1-diphenylethane
m, 1740 nm, 1366 nm, 1726 nm, 2026 nm, 2040 for 1,2,5 triethylbenzene
nm, 1746n for 1,2,4-triethylbenzene
m, 1862 nm, 1832 nm, 1746 nm, 1572 nm, 141 for 1,2,3-triethylbenzene
It is preferable to quantify the composition using a spectrum in the wavelength range of 1 nm to 1900 nm for 4 nm and benzene.

[0021]

EXAMPLES The present invention will be described in more detail with reference to the following examples.

[0022]

Example 1 Ethylbenzene was synthesized by reacting benzene with ethylene using hydrochloric acid as an aluminum chloride cocatalyst as a main catalyst. The initial reaction conditions were set such that the reaction temperature was 110 ° C., the reaction pressure was 0.6 Kg / cm 2 G, the concentration of aluminum chloride as the main catalyst in the reactor was 0.3% by weight, and the auxiliary catalyst in benzene fed to the reactor was The concentration of hydrochloric acid in the catalyst is 1% by weight
Is.

A near-infrared spectrophotometer was installed on the line extending from the cooler at the outlet of the reactor to analyze the condensed reaction solution. Since the analysis is online and the analysis time is short, it can be analyzed in about 1 minute, and the analysis result was viewed and reflected promptly in the operation management of the reactor. Looking at the composition analysis results of the reactants, the concentration of ethylbenzene is lower than the control concentration, so the amount of benzene feed was reduced in three times and the molar ratio was 1%.
I raised it.

As described above, since the deviation from the control standard of the composition of the reaction solution at the outlet of the reactor can be constantly monitored,
When the composition of the reaction liquid deviates from the standard, it is possible to recover the proper composition without wasting time. Table 1 shows the results of analysis by the near infrared rays of the reaction solution, the time required for the analysis, the method for changing the reaction amount, the time until the composition of the controlled reaction solution is restored, and the type of spectrum.

The ratio of the ethyl group of the raw material to the benzene ring is
Of the raw materials to be charged, benzene, ethylene, and polyethylbenzene in which 2 to 6 ethyl groups are added to the benzene ring, the ratio of the ethyl group to the benzene ring is represented by the molar ratio, and is hereinafter referred to as the molar ratio. Only the molar ratio is shown in the state after the final change of the reaction conditions. This is because changes in the feed rate of raw materials and the molar ratio are represented by the molar ratio.

As described above, the rapid control makes it possible to obtain a highly pure ethylbenzene in which the fluctuation of the composition of the reaction product is small, the distillation separation in the purification step is easy.

[0027]

Comparative Example 1 Ethylbenzene was synthesized under the same reaction conditions as in Example 1 except that on-line analysis was not performed. It is necessary to sample the reaction solution every time it is necessary to confirm that the reaction conditions are appropriate values, and to analyze by gas chromatography.If sampling time and analysis time are taken into consideration, it is necessary to change the operating conditions of the reactor. There was a time delay, and quick control was not possible. This time delay was 60 to 90 minutes on average.

Moreover, since these are not automatic, it is not possible to constantly monitor the concentration, and operation management is very rough, and there is a gap between the control concentration and the analysis between the analyzes. It was driving. Looking at the composition analysis results of the reactants, the ethylbenzene concentration was lower than the control concentration, so the amount of benzene feed was reduced in three steps and the molar ratio was increased by 1%.
It took a minute.

Table 2 shows the results of analysis by gas chromatography of the reaction liquid at the outlet of the reactor, the time required for the analysis, the method of changing the manipulated variable, and the time until the composition of the controlled reaction liquid is recovered.

[0030]

Example 2 Using aluminum chloride as a main catalyst and hydrochloric acid as a cocatalyst, ethylbenzene was synthesized by the reaction of benzene and ethylene. The reaction temperature is set to 1 for the initial reaction conditions.
At a temperature of 20 ° C., a reaction pressure of 0.7 kg / cm 2 G, the concentration of aluminum chloride as a main catalyst in the reactor was 0.4% by weight, and the concentration of hydrochloric acid as a cocatalyst in benzene fed to the reactor was 0.8% by weight. is there.

A near-infrared spectrophotometer was installed on the line extending from the cooler at the outlet of the reactor to analyze the condensed reaction solution. Since the analysis is online and the analysis time is short, the analysis can be done in about 1 minute, and the analysis result was seen and promptly reflected in the operation management of the reactor. The composition analysis result of the reaction product shows that the concentration of ethylbenzene is lower than the control concentration, so the amount of benzene feed was reduced in three times and the molar ratio was increased by 1%.

As described above, since the deviation from the control standard of the composition of the reaction solution at the outlet of the reactor can be constantly monitored,
When the composition of the reaction liquid deviates from the standard, it is possible to recover the proper composition without wasting time. Table 1 shows the results of analysis by the near infrared rays of the reaction solution, the time required for the analysis, the method of changing the manipulated value, the time until the composition of the reaction solution being controlled is recovered, and the type of spectrum.

As described above, the rapid control makes it possible to obtain a highly pure ethylbenzene in which the fluctuation of the composition of the reaction product is small, the distillation separation in the purification step is easy.

[0034]

Comparative Example 2 Ethylbenzene was synthesized under the same reaction conditions as in Example 2 except that the on-line analysis was not performed. It is necessary to sample the reaction solution every time it is necessary to confirm that the reaction conditions are appropriate values, and to analyze by gas chromatography.If sampling time and analysis time are taken into consideration, it is necessary to change the operating conditions of the reactor. There was a time delay and quick control was not possible. This time delay is 6 on average
It is 0 minutes to 90 minutes.

Moreover, since these are not automatic, it is not possible to constantly monitor the concentration, and operation management is very rough, and there is a gap between the control concentration and the analysis between analysis. It was driving. Looking at the composition analysis results of the reactants, the ethylbenzene concentration was lower than the control concentration, so the amount of benzene feed was reduced, but the reanalysis result showed that the polyethylbenzene concentration was higher than the control concentration, so this time the polybenzene concentration was higher than the control concentration. The amount of ethylbenzene feed was reduced to finally reduce the molar ratio by 2%. ,
It took 150 minutes.

Table 2 shows the results of analysis of the reaction liquid at the outlet of the reactor by gas chromatography, the time required for the analysis, the method of changing the manipulated variable, and the time until the composition of the controlled reaction liquid is recovered.

[0037]

Example 3 Ethylbenzene was synthesized by the reaction of benzene and ethylene using hydrochloric acid as the main catalyst and aluminum chloride as the cocatalyst. The reaction temperature is set to 12 at the initial setting of reaction conditions.
5 ° C., reaction pressure 0.7 kg / cm 2 G, concentration of main catalyst aluminum chloride in the reactor is 0.4 wt%, concentration of co-catalyst hydrochloric acid in benzene fed to the reactor is 0.9 wt%.
Is.

A near-infrared spectrophotometer was installed on the line extending from the cooler at the outlet of the reactor to analyze the condensed reaction solution. Since the analysis is online and the analysis time is short, the analysis can be done in about 1 minute, and the analysis result was seen and promptly reflected in the operation management of the reactor. Looking at the composition analysis results of the reaction product, the concentration of ethylbenzene was lower than the control concentration, so the amount of ethylene feed was increased to raise the molar ratio by 2%.

As described above, since the deviation of the composition of the reaction solution from the control standard at the outlet of the reactor can be constantly monitored, when the composition of the reaction solution deviates from the standard, the composition is recovered to an appropriate composition without waste in time. It has become possible. Table 1 shows the results of analysis by the near infrared rays of the reaction solution, the time required for the analysis, the method of changing the manipulated value, the time until the composition of the reaction solution being controlled is recovered, and the type of spectrum.

As described above, the composition of the reaction product is little changed by the rapid control, and therefore, the distillation separation in the purification step is easy, and highly pure ethylbenzene can be obtained.

[0041]

Comparative Example 3 Ethylbenzene was synthesized under the same reaction conditions as in Example 3 except that on-line analysis was not performed. It is necessary to sample the reaction solution every time it is necessary to confirm that the reaction conditions are appropriate values, and to analyze by gas chromatography.If sampling time and analysis time are taken into consideration, it is necessary to change the operating conditions of the reactor. There was a time delay and quick control was not possible. This time delay is 6 on average
It is 0 minutes to 90 minutes.

Moreover, since these are not automatic, it is not possible to constantly monitor the concentration, and operation management is very rough, and operation is performed with a deviation from the control concentration occurring between analyzes. It is carried out. The composition analysis result of the reaction product showed that the ethylbenzene concentration was lower than the control concentration, so the ethylene feed amount was increased and the molar ratio was increased by 2%. It took 70 minutes.

Table 2 shows the results of analysis of the reaction liquid at the outlet of the reactor by gas chromatography, the time required for the analysis, the method of changing the manipulated variable, and the time until the composition of the reaction liquid was controlled.

[0044]

Example 4 Ethylbenzene was synthesized by the reaction of benzene and ethylene using hydrochloric acid as an aluminum chloride cocatalyst as a main catalyst. The reaction temperature is set to 105 at the initial setting of reaction conditions
℃, reaction pressure 0.6kg / cm2G, the concentration of the main catalyst of aluminum chloride in the reactor is 0.3% by weight, the concentration of hydrochloric acid of the cocatalyst in benzene fed to the reactor is 0.7% by weight .

A near-infrared spectrophotometer was installed on the line extending from the cooler at the outlet of the reactor to analyze the condensed reaction solution. Since the analysis is online and the analysis time is short, the analysis can be done in about 1 minute, and the analysis result was seen and promptly reflected in the operation management of the reactor. The composition analysis results of the reaction products show that the concentration of ethylbenzene is lower than the control concentration and the concentration of polyethylbenzene is higher than the control concentration. Therefore, the feed amount of aluminum chloride, which is the main catalyst, was 0.4 weight in the reactor. %, The temperature inside the reactor was increased by 5 ° C., and the pressure was increased by 0.05 kg / cm 2. Also, the amount of benzene feed was increased, and the molar ratio was finally reduced by 5%. In addition, these operations were performed in three steps.

As described above, since the deviation from the control standard of the composition of the reaction solution at the outlet of the reactor can be constantly monitored,
When the composition of the reaction liquid deviates from the standard, it is possible to recover the proper composition without wasting time. Table 1 shows the results of analysis by the near infrared rays of the reaction solution, the time required for the analysis, the method of changing the manipulated value, the time until the composition of the reaction solution being controlled is recovered, and the type of spectrum.

In this way, the composition of the reaction product is little changed by the rapid control, and therefore, the distillation separation in the purification step is easy, and highly pure ethylbenzene can be obtained.

[0048]

Comparative Example 4 Ethylbenzene was synthesized under the same reaction conditions as in Example 3 except that on-line analysis was not performed. It is necessary to sample the reaction solution every time it is necessary to confirm that the reaction conditions are appropriate values, and to analyze by gas chromatography.If the sampling time and analysis time are taken into consideration, the operating conditions of the reaction conditions must be changed. There was a time delay and it was not possible to control quickly. This time delay is 60 to 90 minutes on average.

Moreover, since these are not automatic, it is not possible to constantly monitor the concentration, and operation management is very rough, and there is a gap between the control concentration and the analysis between the analyzes. It is carried out. The composition analysis results of the reaction products show that the concentration of ethylbenzene was lower than the control concentration and the concentration of polyethylbenzene was higher than the control concentration, so that the feed amount of the aluminum chloride cocatalyst as the main catalyst was 0. Increase to 4% by weight,
Raise the temperature in the reactor by 5 ° C and increase the pressure to 0.05 kg / cm
Raised 2. Also, the amount of benzene feed was increased, and the molar ratio was finally reduced by 5%. In addition, these operations were performed in three steps. It took 210 minutes.

Table 1 shows the results of analysis of the reaction liquid at the outlet of the reactor by gas chromatography, the time required for the analysis, the method of changing the manipulated variable, and the time until the composition of the reaction liquid was controlled.

[0051]

Example 5 Ethylbenzene was synthesized by the reaction of benzene and ethylene using hydrochloric acid as an aluminum chloride co-catalyst as a main catalyst. The reaction temperature is set to 115 as the initial set value of the reaction conditions.
℃, reaction pressure 0.7kg / cm2G, the concentration of the main catalyst of aluminum chloride in the reactor is 0.4% by weight, the concentration of hydrochloric acid of the cocatalyst in benzene fed to the reactor is 0.7% by weight .

A near-infrared spectrophotometer was installed on the line extending from the cooler at the outlet of the reactor to analyze the condensed reaction solution. Since the analysis is online and the analysis time is short, the analysis can be done in about 1 minute, and the analysis result was seen and promptly reflected in the operation management of the reactor. The composition analysis result of the reaction product showed that the concentration of ethylbenzene was lower than the control concentration. Therefore, the amount of benzene feed was reduced, the amount of polyethylbenzene feed was increased, and the molar ratio was increased by 5%. Note that these operations were performed twice.

As described above, since the deviation from the control standard of the composition of the reaction solution at the outlet of the reactor can be constantly monitored,
When the composition of the reaction liquid deviates from the standard, it is possible to recover the proper composition without wasting time. Table 1 shows the results of analysis by the near infrared rays of the reaction solution, the time required for the analysis, the method of changing the manipulated value, the time until the composition of the reaction solution being controlled is recovered, and the type of spectrum.

As described above, the composition of the reaction product is little changed by the rapid control, and therefore, the distillation separation in the purification step is easy, and highly pure ethylbenzene can be obtained.

[0055]

Comparative Example 5 Ethylbenzene was synthesized in the same manner as in Example 5 except that the reaction solution was not analyzed by near infrared rays. It is necessary to sample the reaction solution every time it is necessary to confirm that the reaction conditions are appropriate values, and to analyze by gas chromatography. Considering the sampling time and analysis time, until the operating conditions of the reactor are actually changed There was a time delay and it was not possible to control quickly. This time delay is 60 to 90 minutes on average.

Moreover, since these are not automatic, it is not possible to constantly monitor the concentration, and operation management is very rough, and operation is performed with a deviation from the control concentration occurring between analyzes. Is going. The composition analysis results of the reaction product show that the concentration of ethylbenzene is higher than the control concentration and the concentration of polyethylbenzene is lower than the control concentration, so the amount of benzene feed is reduced, the amount of polyethylbenzene feed is increased, and finally The molar ratio was increased by 5%. The feed amount of polyethylbenzene was increased and the molar ratio was increased by 5%. Note that these operations were performed twice. It took 210 minutes.

Table 2 shows the analysis results of the reaction liquid at the outlet of the reactor by gas chromatography, the time required for the analysis, the method of changing the manipulated variable, and the time until the composition of the controlled reaction liquid is recovered.

[0058]

[Table 1]

[0059]

[Table 2]

[0060]

INDUSTRIAL APPLICABILITY The reactor control method using near-infrared rays according to the present invention reflects the composition change of the reactants in the operation of the reactor more quickly than the conventional method, synthesizes a certain reactant, and has a high level. It is possible to drive.

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Claims (1)

[Claims] 1. A method for controlling the operation of a reactor for synthesizing a reaction product, wherein a composition of the reaction product at the outlet of the reactor is analyzed by near-infrared spectrum, and a raw material supplied to the reactor using the obtained measurement value. A method for controlling reaction by near-infrared radiation, characterized in that the composition of the reactant at the outlet of the reactor is made constant by changing the amount or ratio of