JP3142280U - Organic carbon measuring device - Google Patents

Abstract

An organic carbon measurement apparatus capable of easily measuring the amount of nonvolatile organic carbon in a sample containing a volatile component.
A gas supply flow path is provided for supplying a gas of the same type or a different type to a carrier gas in addition to a carrier gas to a sample introduction part via an on-off valve (electromagnetic valve). Thus, after the sample is loaded, the electromagnetic valve 11 is opened and a large amount of gas is supplied to the sample introduction unit 5 to promote the volatilization of the volatile components in the sample. Can be moved into the combustion tube 4 to measure the remaining non-volatile organic carbon.
[Selection] Figure 1

Description

  The present invention relates to an organic carbon measuring apparatus, and more particularly to an organic carbon measuring apparatus that can easily quantify only non-volatile organic carbon by removing volatile components such as an organic solvent in a sample.

  To measure total organic carbon (TOC) in a solid sample, a sample from which inorganic carbon has been removed in advance by acid treatment is introduced into a combustion tube heated in an electric furnace and oxidized while flowing a carrier gas containing oxygen. A method of detecting and quantifying carbon dioxide generated by heating together with a catalyst to oxidize an organic substance in a sample with an infrared detector is known.

FIG. 2 shows an example of the configuration of a conventional TOC measuring apparatus.
In the figure, a carrier gas composed of pure oxygen or oxygen-containing gas is controlled in flow rate by a flow rate control unit 1 through an introduction path L, and a sample introduction unit 5 and a combustion tube 4 connected to the sample introduction unit 5 are connected. It flows through and further flows to the detection unit 9 through the cooling unit 7 and the dehumidifying unit 8. The sample introduction part 5 is a metal hollow cylindrical body, the combustion tube 4 is connected to one end thereof, and the other end is closed by a sample introduction port lid 51 that can be opened and closed. A sample to be measured is placed on a sample boat 6 which is a boat-shaped sample container. A handle 61 penetrating the sample introduction port lid 51 is attached to the sample boat 6, and the sample can be moved into the combustion tube 4 by pushing the handle 61. The quartz combustion tube 4 is heated to around 900 ° C. by the electric furnace 3, and an oxidation catalyst 41 is loaded therein.

The measurement of TOC by the conventional configuration apparatus shown in FIG. 2 is as follows.
The sample boat 6 on which the sample is placed is inserted into the sample introduction unit 5, the sample introduction port lid 51 is closed, and a carrier gas adjusted to a predetermined flow rate is flowed. Next, when the sample boat 6 is moved into the combustion tube 4, the organic substance in the sample is burned to become carbon dioxide, cooled and dehumidified, and detected by the infrared absorption method at the detection unit 9. The total amount is measured.

  Further, a low temperature heating section (not shown) of 100 to 200 ° C. is provided in the front stage of the combustion tube 4, and a sample is first placed in the low temperature heating section to vaporize volatile components, and the combustion pipe 4 in the subsequent stage is similar to the above. VOC / NVOC measurement device that measures volatile organic carbon (VOC) by converting it into carbon dioxide and then moves the sample into the combustion tube 4 to measure the remaining nonvolatile organic carbon (NVOC) Has also been developed (see, for example, Patent Document 1).

JP-A-5-302920

  When evaluating the cleanliness after washing of pharmaceutical manufacturing equipment (for example, chemical containers, etc., hereinafter simply referred to as equipment), the surface of the equipment is wiped with an inorganic swab material (eg, quartz glass cloth), and the swab material is removed. There is a method of evaluating the cleaning effect by measuring the amount of organic carbon on the equipment surface by burning. However, when the equipment is cleaned with an organic solvent such as alcohol, the organic solvent used for cleaning remains on the equipment surface, so if you wipe it off with a swab material, the organic solvent will adhere to the swab material along with the equipment surface residue. End up. Therefore, not only the amount of organic carbon from the equipment surface residue to be measured, but also the amount of organic carbon from the organic solvent used for cleaning is added, and it is a problem that only the equipment surface residue cannot be measured accurately. .

This problem can be solved by measuring the organic solvent as VOC and the equipment surface residue as NVOC using the VOC / NVOC measuring apparatus described above. However, the VOC / NVOC measurement device is more expensive than the TOC measurement device, and the operation is more complicated, and the target sample is limited at present, so it is difficult to use for this purpose.
This invention is made | formed in view of such a situation, and it aims at providing the organic carbon measuring apparatus which can measure only NVOC in the sample containing a volatile component simply.

  In order to solve the above-mentioned problems, the present invention provides a gas supply flow path for supplying a gas of the same or different type as the carrier gas in addition to the carrier gas to the sample introduction section through the introduction path provided with the on-off valve . As a result, after loading the sample, the on-off valve is opened and a large amount of gas is supplied to the sample introduction part to promote volatilization of the volatile components in the sample, and the sample is burned after all the volatile components have been volatilized. It is possible to measure the remaining nonvolatile organic carbon by moving it into the tube.

According to the present invention, only a slight improvement is made to the conventional TOC measuring device. For example, when evaluating the cleaning effect when a pharmaceutical manufacturing facility is cleaned with an organic solvent, the influence of the organic solvent is eliminated and the surface of the facility is removed. It is possible to easily measure the amount of carbon in the organic substance remaining in the substrate.
In addition, the present invention is not limited to the above example, and it is generally possible to measure NVOC in a sample containing VOC.

  The present invention is an organic carbon measuring device provided with a gas supply flow path for supplying a gas of the same type or a different type to a carrier gas in addition to a carrier gas to a sample introduction part via an on-off valve.

  FIG. 1 shows an embodiment of the present invention. In the figure, the same reference numerals are given to the same components as those in the conventional example shown in FIG. 2, and the description thereof is omitted here. This embodiment differs from the conventional configuration in that it branches from the upstream carrier gas flow path of the flow rate control unit 1, passes through the electromagnetic valve 11, and again merges with the carrier gas by the three-way joint 13 to reach the sample introduction unit 5. The gas supply flow path 10 is provided. Reference numeral 12 denotes a resistance tube provided for supplying an appropriate amount of gas.

In the configuration shown in FIG. 1, the procedure for measuring NVOC in a sample containing VOC is as follows.
(1) A sample is placed on the sample boat 6 and inserted into the sample introduction unit 5, and the sample introduction port lid 51 is closed.
(2) Open the solenoid valve 11. As a result, a gas whose amount is approximately twice the normal carrier gas flow rate (as an example, 0.5 L / min) flows through the sample introduction unit 5 and the volatilization of the volatile components in the sample is promoted.
(3) Volatilized volatile components are carried into the combustion pipe 4 by the carrier gas, converted into carbon dioxide by the action of the oxidation catalyst 41, and reach the detection unit 9 via the cooling unit 7 and the dehumidifying unit 8. The output signal from the detection unit 9 is displayed on a monitor (not shown).
(4) The state of volatilization of volatile components is checked by the monitor display, and when the completion of volatilization is confirmed, the solenoid valve 11 is closed.
(5) The handle 61 is pushed in, the sample boat 6 is moved into the combustion tube 4, and NVOC is measured in the same process as the conventional TOC measurement.

  The above is an example of using the same type of gas as the carrier gas (pure oxygen or a gas containing oxygen) as a gas to be added to promote volatilization, but expensive pure oxygen or the like is used to promote volatilization. Since it is not necessary, cheaper nitrogen or air may be used. Moreover, you may use the manual or electrically operated on-off valve which turns on and off a flow path instead of the solenoid valve 11 shown in FIG. Furthermore, a configuration in which the three-way joint 13 is omitted and the downstream end of the gas supply channel 10 is directly connected to the sample introduction unit 5 is also possible.

  The present invention can be used to measure organic carbon.

It is a figure which shows one Example of this invention. It is a figure which shows the example of a conventional structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Flow control part 3 Electric furnace 4 Combustion tube 5 Sample introduction part 6 Sample boat 7 Cooling part 8 Dehumidification part 9 Detection part 10 Gas supply flow path 11 Solenoid valve 12 Resistance pipe 13 Three-way joint 41 Oxidation catalyst 51 Sample introduction cover 61 Pattern L Introduction route

Claims (1)

  Generated by connecting a sample introduction part into which a carrier gas containing oxygen is introduced via an introduction path and a combustion tube, and moving the sample inserted into the sample introduction part into the combustion tube for combustion In the organic carbon measuring device for detecting the carbon dioxide to be quantified and quantifying the amount of organic carbon in the sample, in addition to the carrier gas to the sample introduction part via an on-off valve, the same or different type of gas as the carrier gas An organic carbon measuring device characterized in that a gas supply flow path for supplying gas is provided in parallel with the introduction path.

Images