JPS6044849A - Thermogravimetric measuring apparatus - Google Patents

Abstract

PURPOSE:To perform thermogravimetric measurement, by connecting a trap container, which has an exhaust pipe at a part higher than an opening, so as to surround the lower opening of a reaction container, wherein a sample container is suspended and which is heated by a heater, and collecting yielded volatile gas. CONSTITUTION:A sample is mounted on a sample container 11. The container 11 is suspended in a reaction container 10 from a pipe body 1 of a suspension type thermogravimetric measuring apparatus. A heating furnace 12, which is provided around the reaction container 10, heats the sample container 11 at a constant speed through a temperature regulating device 18. The yielded volatile gas from the sample is exhausted to a trap container 15 by a carrier gas from an injecting port 7 through an opening 10'. The trap container is kept at a room temperature. The yielded gas having a high boiling point is condensed and deposited as a trapped material 20. The yielded gas having a low boiling point is exhausted through an exhaust pipe 14. Since only the low-boiling point gas passes through the exhaust pipe 14, the gas is not condensed and the pipe is not clogged. The flow rate of the gas is not fluctuated. Thus precise thermogravimetric measurement can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermogravimetric measuring device capable of collecting volatile components, and particularly to a thermogravimetric measuring device that can collect volatile components that evaporate from a sample when the sample is heated during thermogravimetric measurement. Among these, the present invention mainly relates to a thermogravimetric measuring device equipped with a trap device that can collect high-boiling point components and allow low-boiling point components to flow out.

(Prior art) Thermogravimetry measures the mass of a sample as a function of temperature while changing the temperature applied to the sample at a constant rate.
It measures the weight loss due to dehydration and decomposition reactions from a sample during heating, and the weight increase due to adsorption and oxidation reactions, and is especially widely used to understand the state of polymeric substances. When measuring thermal decomposition reactions of polymeric substances such as plastics and coal using a thermogravimetric measuring device, high boiling point components that are solid or liquid at room temperature are volatized and produced. According to one type of thermogravimetric measuring device that uses a pan-type balance, the volatilized gas of the high-boiling components mentioned above enters the balance section and adheres to the balance system, resulting in the influence of convection on the balance section. There is a drawback that measurements cannot be performed under optimal conditions due to the influence of buoyancy. Therefore, recently, hanging type thermogravimetric measuring devices are often used. In a hanging type thermogravimetric measuring device, the volatilized gas from the sample is caused to flow into the lower part of the reaction tube that heats the sample using a purge gas, and is discharged outside the device through a thin tube such as a vinyl tube. At the time of discharge, the volatilized gas of high boiling point components condenses in thin tubes such as vinyl tubes that are at a temperature lower than the temperature of the reaction tube and becomes liquid or solid again. I get stuck. This causes fluctuations in the gas flow rate, which causes buoyancy fluctuations to the hanging balance portion of the thermogravimetry device, which has the drawback of making it impossible to accurately measure weight. Furthermore, it has been difficult to analyze volatile components condensed in thin tubes such as vinyl tubes.

(Object of the Invention) The present invention solves the drawbacks of the prior art as described above, and is aimed at dissolving the volatilized gases, which are mainly high-boiling components among the volatile components volatilized from the heated sample, in the lower part of the reaction vessel. By collecting the gas using a low-temperature trap container, it is possible to prevent the condensation of the volatile gases of high boiling point components in the exhaust path, including thin tubes such as vinyl tubes, and to analyze the volatile gases of low boiling point components. It is an object of the present invention to provide a thermogravimetric measuring device that allows a high boiling point component substance introduced into the device and collected in a trap container to be used as a sample for component analysis.

(Structure of the Invention) The present invention is directed to a trap that collects vaporized gas evaporated from a sample placed on a sample container that is suspended in a reaction container and heated, from an opening of the reaction container at a temperature lower than that of the sample container. The high boiling point volatile product gas that becomes a liquid or solid again at the low temperature is condensed and collected in the trap container, and the low boiling point volatile product gas that becomes a gas at the low temperature is trapped. By discharging from the exhaust pipe of the container, it is possible to perform precise thermogravimetric measurements and easily analyze the components of volatile products without clogging the vinyl tube tonneau exhaust gas path due to condensation of high boiling point volatile products. It is something to do.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the thermogravimetric measuring device of the present invention will be described below with reference to the drawings.

(Example) (Fig. 1) Fig. 1 shows a side sectional view of an example of the thermogravimetric measuring device of the present invention.

In the figure, ■ is a tube housing the support part of the hanging thermogravimetry device, and 7 is a carrier gas injection hole through which a carrier gas such as helium or nitrogen is injected, which is connected to the tube L. . Reference numeral 3 denotes a support portion of a hanging type thermogravimetric measuring device, which is supported by a support device (not shown) with respect to the tube body 1. 2
is an arm, and 4 is a sample container support suspended from the tip of arm 2, and at its lower end is a container 1 on which a sample is placed.
1 is hanging. Reference numeral 6 is an opening provided on the side surface of the tube body 1, and 5 is a packing, which is filled between the opening 6 and the side wall of the connecting pipe 8. IO is a reaction vessel, the upper part of which has a tapered part that gradually narrows upward, and is fitted snugly into the widening part of the connecting tube 8 that gradually widens downward. 9 is a carrier gas guide section. The lower part of the reaction vessel 10 is provided with a gently tapering part, which extends into a straight tube shape, and has an opening 10' at the bottom thereof. ■2 is reaction container 1
This is a heating furnace that is installed on the side of 0 and is made of, for example, nichrome wire. ■5 is a high boiling point volatile product that becomes liquid or solid again at room temperature! It is a trap container maintained at room temperature that collects gas at its bottom, and is connected to a gas analyzer such as a gas chromatograph or mass spectrometer (not shown) to capture the low boiling point volatile product gas that is a gas at room temperature. An exhaust pipe 14 is provided. The position at which the exhaust pipe 14 is attached to the trap container 15 must be higher than the height at which the opening IO of the reaction container 20 is located. This is because the high-boiling point volatile product gas discharged from the opening 10 of the reaction vessel 10 and becoming liquid or solid again at room temperature is not collected at the bottom of the trap container 15 and is discharged from the exhaust pipe 14 together with the low-boiling point volatile product gas. This is because it is discharged from the

(2) 3 is a recessed part of the trap vessel 15, which is fitted snugly into the lower concave part of the reaction vessel IO.

20 indicates high boiling point volatile products condensed and collected at the bottom of the trap vessel 15 kept at room temperature. 16
is a thermocouple placed near the sample container 11, and its detected temperature is applied to the temperature controller 18 via a lead wire 17. Reference numeral 18 denotes a temperature controller, which supplies power to the heating element 12 via a lead wire 19 to heat the sample container 11 at a constant rate of, for example, 10° C./minute while monitoring the temperature detected by the thermocouple 16. Add.

The operation of the device shown in FIG. 1 will be explained. A carrier gas such as helium or nitrogen is injected at a predetermined flow rate from the carrier gas injection hole 7 of the tube l. This carrier gas flows around the sample container 11 via the connecting pipe 8 and the carrier gas guide section 9, and passes through the trap container 1 through the opening 10' of the reaction container IO.
It is discharged at 5.

Electric power is supplied from the temperature controller 18 to the heating furnace 12 provided around the reaction vessel 10 via a lead wire 19.
The sample container 11 is heated at a constant rate of 0° C./min. As the temperature rises, volatile components contained in the sample placed in the sample container 11 are sequentially volatilized to become a volatilized gas, which is released into the carrier gas. Of the volatile gas discharged together with the carrier gas into the trap container 15 kept at room temperature, only the high boiling point gas that becomes liquid or solid again at room temperature is condensed in the trap container 15 and collected at its bottom. The collected matter 20 is deposited thereon. The low boiling point volatilized gas, which is in the form of a gas -th at room temperature, is exhausted through the exhaust pipe 14. Since the sample introduction part of an analyzer such as a gas chromatograph or a mass spectrometer (not shown) is directly connected to this exhaust pipe 14 via a vinyl tube, it is possible to avoid contamination of the analyzer with a low boiling point. Capable of analyzing volatile gases. The trapped material 20 that has been collected in the trap container 15 and has become a liquid or solid is removed from the trap container 15, sampled, and analyzed for components of high boiling point volatile products using an analysis device such as a liquid chromatography device. can also be done.

Note that by configuring the thermogravimetric measuring device including the reaction vessel 10, trap vessel 15, etc. to be pressure resistant, thermogravimetric measurement can be performed even under high pressure conditions.

(Effects of the Invention) As explained above, according to the present invention, the trap container maintained at room temperature is connected to the lower part of the thermogravimetric measuring device, and the exhaust pipe provided in the trap container is extended into the trap container. Since it is installed at a position higher than the opening of the reaction vessel, the vaporized gas produced by volatilization from the sample in the reaction vessel of the thermogravimetric measuring device is high enough to become solid or liquid again at room temperature. The boiling point volatile gas can be collected in a trap container, and the low boiling point gas that is a gas at room temperature can be discharged from the trap container. There is no clogging due to gas condensation, and therefore accurate thermogravimetric measurements can be performed without causing fluctuations in the gas flow rate.

[Brief explanation of the drawing]

FIG. 1 shows a side sectional view of a first embodiment of the thermogravimetric measuring device of the present invention. In the figure, ■ is a tube body, 2 is an arm, 8 is a support part, 4 is a sample container support body, 5 is a ζ skin, 6 is an opening, 7 is a carrier gas injection hole, 8 is a connecting tube, and 9 is a guide part , IO is a reaction vessel, 10' is its opening, 11 is a sample vessel, 12 is a heating furnace,
18 is the seed part of the trap container, 4 is the exhaust pipe, 15 is the trap container, 16 is the thermocouple, 17 and 19 are the lead wires, 18
is a temperature regulator, and 20 indicates a high-boiling volatile product.

Claims (2)

[Claims] (1) In a thermogravimetric measuring device comprising a reaction vessel from which a sample vessel is suspended and which has an opening at the lower part thereof, and a heating element that heats the reaction vessel, the heating element is arranged so as to surround the opening provided at the lower part of the reaction vessel. A trap container is connected to the trap container and has a temperature lower than that of the reaction container, an exhaust pipe is provided in the trap container for exhausting a low boiling point volatile product gas, and the mounting position of the exhaust pipe with respect to the trap container is set in the same direction as that of the reaction container. A thermogravimetric measuring device characterized by being located at a higher position than the height of the opening provided at the bottom. (2) The thermogravimetric measuring device according to claim 1, characterized in that an exhaust pipe attached to the trap container is connected to an analysis device.