JPH0722697B2 - Adsorbent testing equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to a test device for measuring the adsorption characteristics of adsorbents such as activated carbon, zeolite, air cleaners, deodorants and the like.

Conventional technology Knowing the adsorption capacity of adsorbents such as activated carbon, zeolite, and other air purifiers and deodorants is extremely important in designing air purifiers and deodorizers that use these adsorbents. . In the adsorbent used for the above purposes,
Important properties are adsorption rate and life performance. The performance of air purifiers and deodorizers cannot be predicted without knowing at least these characteristics of the adsorbent in advance. Conventionally, the equilibrium adsorption amount obtained from the adsorption isotherm was measured as a static characteristic value that represents the life. A breakthrough curve was measured as a dynamic characteristic. In this way, by measuring the equilibrium adsorption amount of the adsorbent alone and the breakthrough curve in advance, it is possible to predict the life of the air cleaning device and the deodorizer. On the other hand, in order to know the adsorption rate, the adsorbent is actually installed in an air purifier or deodorizer, and this is operated in a space filled with odors, for example, in a box of 1 m ³ , Was being measured.

Problems to be Solved by the Invention However, in the conventional method of measuring the adsorption rate,
There are the following issues.

Firstly, it is necessary to prepare a large amount of adsorbent, secondly, it is necessary to carry out work such as making it into a filter so as to be incorporated into an air purifier or deodorizer, and thirdly, a large amount of odor is generated. It is necessary. In other words, it was inefficient in terms of time and money.

Therefore, the first object of the present invention is to enable the adsorption rate to be measured in a short time with a small amount of adsorbent, and the second object is to obtain a dynamic equilibrium adsorption amount simultaneously with the adsorption rate. .

Means for Solving the Problems The first means for achieving the first object is to provide a gas holder, a pump for feeding gas, a valve and a flow meter for adjusting the flow rate of gas, and a gas concentration and flow rate. A mixing circulation system for pre-stabilization, and an adsorption circulation system having a column containing an adsorbent, the mixing circulation system and the adsorption circulation system are provided in parallel on the upstream side of the gas holder, and the pump is a gas The valve and the flow meter were provided downstream of the holder between the pump and the mixing circulation system and the adsorption circulation system so that gas could flow to either the mixing circulation system or the adsorption circulation system. This is the adsorbent testing device.

The second means for achieving the second object is to open a part of the flow path on the downstream side of the pump constituting the first means, and to allow a flow on the downstream side of the open part and on the upstream side of the gas holder. This is an adsorbent testing device configured so that a part of the passage is closed and the mixed circulation system is depressurized.

The first means of operation works as follows.

The gas holder occupies most of the volume of the entire apparatus, and gas and air are mixed in the gas holder. The gas mixed here is circulated in a mixing circulation system by a pump.
The flow meter is common to the mixing circulation system and the adsorption circulation system, and when the mixing circulation system is flowed in advance, the flow rate and concentration are stabilized by adjusting the valve and the flow meter to the same as the test flow rate. On the other hand, the adsorbent to be tested is set on the column in the adsorption circulation system, and a stable gas is flown into the adsorption circulation system. The gas is adsorbed on the adsorbent, and the gas concentration is made uniform by the gas holder. By analyzing the time change of the gas concentration in the adsorption circulation system, the adsorption rate of the adsorbent can be known. Furthermore, the relationship between the contact time between the gas and the adsorbent and the adsorption rate can be known by changing the flow velocity with the flow meter.

The second means operates as follows.

When a part of the flow path of the mixing circulation system located on the side opposite to the pump with respect to the gas holder is closed and the immediate vicinity thereof is opened to operate the pump, the pressure of the mixing circulation system including the gas holder is reduced. As a result, by injecting a large amount of gas or chemical into the gas holder for vaporization, stopping the pump, introducing the atmosphere, and restarting the operation of the pump, the system can be made to have a uniform high concentration. By properly selecting the gas farming degree and the amount of the adsorbent, the equilibrium adsorption amount at an arbitrary flow rate can be measured.

Example The configuration of an example of the present invention will be described with reference to FIG. FIG. 1 is a wiring diagram of an adsorbent testing device of the present invention. First
In the figure, 1 is a gas holder consisting of 30 glass bottles, 2 is a diaphragm type pump for sending gas (manufactured by Vacuum Kiko Co., Ltd., DA-60S, whose diaphragm is treated with fluorine resin), 3 is a pressure control valve, The discharge pressure of the pump 2 is adjusted. 4 is a pressure gauge, with a safety device,
The buzzer sounds and the pump is stopped before the pressure inside the system rises to a dangerous level. 5 is a flow meter (flow meter made by Kojima Seisakusho, maximum flow rate 50 / min),
6 is a flow control valve. The system consisting of 7.8 is a mixed circulation system, and the system consisting of 7.9 is an adsorption circulation system. Reference numeral 10 is a mixing sampling port, which is a T-shaped glass tube having a rectangular tube with a silicone rubber plug at the opening. 11 is an adsorption sampling port, which has the same structure as the mixing sampling port. Numeral 12 is a sample column, which is divided into two parts. The upper half is made of glass and the lower half is made of stainless steel. Silicon rubber packing is placed between the upper and lower parts, and clamped tightly. The adsorbent sample is a stainless steel cell 13 (inner diameter
36mm) and set it on the sample column. At this time, a non-woven fabric is laid on the bottom of the cell 13 so that the fine powder of the adsorbent is not spilled. Reference numeral 14 is a gas or chemical injection port from which the gas holder 1 is injected with a syringe or the like. 15 is a solenoid valve for exhausting gas or air of the system, 16 is a solenoid valve for sucking the atmosphere, 17 is a solenoid valve for separating the exhaust side and the suction side, 18 is a vacuum gauge for checking the vacuum degree of the system, 19 is a vacuum Solenoid valves that are closed from the end of operation to the end of atmospheric suction, and 20 to 23 are solenoid valves that switch between the mixing circulation system and the adsorption circulation system. For the piping, we used fluorine resin (inside diameter 8 mm, outside diameter 10 mm), which is easy to process, as much as possible, and when it was unavoidable, we used glass tubes (inside diameter 7 mm and outside diameter 10 mm). In addition, a heat-shrinkable tube made of fluorine resin or a joint made of stainless steel was used for connection. This allows
The piping can be shortened and the pressure and flow velocity can be stabilized.

Next, an example of measuring the adsorption rate and the equilibrium adsorption amount, and the operation of the test apparatus at that time will be described.

Measurement Example 1 Adsorption rates of acetaldehyde were measured for adsorbent A prepared by kneading sulfanilic acid into clay minerals and granulated to 6/8 mesh, and adsorbent B prepared by adsorbing aniline on 6/8 mesh coconut shell activated carbon. The room temperature is 22 to 25 ° C and the relative humidity is 50 to 60%. The measurement procedure is as follows.

1. Set the cell 13 containing 2.8 g of the adsorbent in the sample column 12.

2. Insert 2 cc of acetaldehyde saturated gas from the inlet 14 with a syringe.

3. Open the solenoid valves 17, 19, 20, 21 and the flow rate control valve 6 and close the solenoid valves 15, 16, 22, 23 to operate the pump 2. Further, the flow rate is adjusted to 27 / min by the flow rate controller 6 and the flow rate meter 5 so that the flow rate becomes the same as the flow rate of the air cleaning device. Operate for 30 minutes in this state to stabilize the gas concentration.

4. Collect the gas from the mixing sampling port 10 with a syringe and analyze it by gas chromatography with FID (Flame ionization detector), and use this as the initial concentration. Here, the operation is performed so that the initial concentration is about 50 ppm.

5. Close the solenoid valves 20 and 21, and open the solenoid valves 22 and 23. At this point, adsorption is started.

Gas was sampled from the adsorption sampling port 11 with a syringe every 6, 5 or 10 minutes and analyzed by gas chromatography to obtain the adsorption curve of FIG.

7. When the measurement is completed, the sample column 12 is removed, the pump 2 is continuously operated to suck the atmosphere, and the remaining gas is exhausted. Do this for about 20 minutes.

8. Then, close the solenoid valves 22 ・ 23 ・ 17, and close the solenoid valves 20 ・ 21 ・ 15.
・ Open 16 and suck the atmosphere through the solenoid valve 16
More mixed circulation gas is exhausted. Do this for about 20 minutes.

The inside of the apparatus is cleaned by these operations 7 and 8.

In FIG. 2, a-1 is the adsorption curve of adsorbent A, b-1
Is the adsorption curve of adsorbent B. Here, it measured by the conventional method shown below. The 4th isothermal adsorption line of acetaldehyde
Shown in the figure. a-3 is an isotherm adsorption line of adsorbent A, and b-3 is an isotherm adsorption line of adsorbent B. The equilibrium adsorption amount at each gas concentration can be known from this data.
It can be seen that the difference in ability in Fig. 2 is much larger than the difference in ability around ppm. In addition, the isothermal adsorption line in Fig. 4 shows that 2g of the sample is put in a glass bottle with a capacity of 3.97, a predetermined amount of gas is added, and then the sample is left in a constant temperature bath at 25 ° C to measure the gas concentration and reach equilibrium. It was obtained by determining the relationship between the gas concentration and the gas adsorption amount.

Measurement Example 2 The equilibrium adsorption amount of acetaldehyde of the adsorbent A was measured. Room temperature is 22-25 ° C, relative humidity is 50-60%, flow rate is 27 /
Minutes. The operation was performed as follows.

1. Set the cell 13 containing 10 g of the adsorbent in the sample column 12.

2, solenoid valves 16, 17, 22, 23 are closed, solenoid valves 19, 20, 21, ...
15. Open the flow rate control valve 6 and operate the pump 2 to reduce the pressure in the gas holder 1 to about 20 cmHg, close the solenoid valves 15 and 19 and stop the pump 2.

3. Acetaldehyde solution with a syringe gas inlet 14
And let it evaporate.

4. Open the solenoid valves 16 and 17 to suck in the atmosphere and return to normal pressure.

5. After that, the same operations as the operations 3 to 8 in the measurement example 1 are performed.
The initial concentration was adjusted to about 1000 ppm. As a result of the above measurement, the adsorption curve a-2 shown in FIG. 3 was obtained. From this, the equilibrium concentration was 5 ppm, and the amount adsorbed at this time was 54 mmg. As a result, a flow rate of 27 / min (flow rate of 4
5 cm / sec) and the equilibrium adsorption amount at 5 ppm acetaldehyde is 5.
It will be 4 mg / g. This value is about half of the static equilibrium adsorption amount obtained from FIG. If the solenoid valve opening / closing operation and the pump operation stop are performed by microcomputer control, the operation becomes smooth, more accurate measurement can be performed, and safety is enhanced.

EFFECTS OF THE INVENTION As described above, the adsorption rate can be measured easily and accurately in a short time with a small amount of the adsorbent. In addition, since a high concentration gas can be used, the dynamic equilibrium adsorption amount can be measured. In addition, the flow rate can be set arbitrarily and various gases can be mixed. As described above, according to the adsorbent test device of the present invention, it is possible to perform a test suitable for the purpose of an air cleaning device or a deodorizer using the adsorbent, and to predict the adsorption rate and the life depending on the actual use conditions. You can

[Brief description of drawings]

FIG. 1 is a piping diagram of an adsorbent test apparatus according to an embodiment of the present invention, FIG. 2 is an example of an adsorption curve measured by the adsorbent test apparatus, and FIG. 3 is an adsorbent test apparatus. An example of the measured adsorption curve for obtaining the equilibrium adsorption amount, FIG. 4 is an isotherm adsorption line of the adsorbent measured by the conventional method. 1 ... Gas holder, 2 ... Pump, 5 ... Flowmeter, 12
…… Sample column.

Claims (2)

[Claims] 1. A gas holder, a pump for feeding gas, a valve and a flow meter for adjusting the flow rate of gas, a mixing circulation system for preliminarily stabilizing the concentration and flow rate of gas, and a column for storing an adsorbent. And an adsorbing circulation system having the admixture circulating system and the adsorbing circulation system provided in parallel to the upstream side of the gas holder, the pump downstream of the gas holder, and the valve and flow meter mixed with the pump. An adsorbent testing device which is provided between a circulation system and an adsorption circulation system so that gas flows through either the mixing circulation system or the adsorption circulation system. 2. A part of the flow path on the downstream side of the pump is opened, and a part of the flow path on the downstream side of the open part and on the upstream side of the gas holder is closed to reduce the pressure of the mixing circulation system. The adsorbent testing device according to claim 1.