Sample chamber for testing adsorption isotherm of material

Abstract

The invention relates to a sample chamber for detecting the property of a material, in particular relates to a sample chamber for testing an adsorption isotherm of a material, and solves the problems of large dead size, high gas resistance and difficulty in dismounting and cleaning of the conventional steel container sample chamber and the problem that the tested material cannot be in direct contact with a temperature measurement thermocouple. The sample chamber consists of a sample pipe (8), the temperature measurement thermocouple (9), a pressure head nut (4), a pressure head (3), a filter net or quartz cotton (5), a four-way gas pipe (7), a connection steel pipe (2), a quick joint (1) and a sealing pad or sealing ring (5), wherein the quick joint is connected with one end of the pressure head through the connection steel pipe; the pressure head nut is sleeved on the pressure head; the filter net or quartz cotton is placed in a threaded hole in the other end of the pressure head and is connected with the four-way gas pipe; the pressure head nut is in threaded connection with the sample pipe; the temperature measurement thermocouple is welded at the bottom of the sample pipe; and the sealing pad or the sealing ring is arranged between the pressure head and the sample pipe.

Description

technical field [0001] The invention relates to a sample chamber for material performance testing, in particular to a sample chamber for material adsorption isotherm testing. Background technique [0002] The adsorption isotherm is an important characteristic curve for studying various properties of materials. Through it, parameters such as adsorption platform pressure, platform width and slope, hysteresis coefficient, and reversible adsorption capacity can be directly obtained, and then the adsorption reaction enthalpy and reaction entropy can be regressed according to the adsorption platform pressure at different temperatures and the Van’t Hoff formula. These parameters have extremely important theoretical and practical guiding significance for the research, development and utilization of materials. At present, people generally use the volumetric method test system to test the material adsorption isotherm. The principle of the volumetric test is to calculate the change o...

AI Technical Summary

Problems solved by technology

The disadvantage of the existing sample chamber for material adsorption isotherm testing is that many materials will be pulverized to produce a large number of micron-sized particles after repeated adsorption, or the original state of the material is powder state, and the test isotherm adsorption process involves vacuuming the system. Then it is inevitable that particles will flow inside the system, destroying the sealing performance of the valve, or some sample chambers are equipped with filters, but the filters cannot be disassembled, cleaned or replaced very well, resulting in that after a long period of use, one end of the filter will be damaged. A lot of powder particles are accumulated, and these powder particles themselves will adsorb gas, so it will eventually affect the correctness of the test data

However, the sample chamber is connected to the test system through threads, and the sealing performance is likely to deteriorate after a small number of uses, or the sealing gasket needs to be replaced before each test, and the test cost is significantly increased

Moreover, the reliability of the threaded connection is not very good in practice, and it is often easy to cause the test gas to leak outwards. At the same time, after the sample is tested, it is easy to cause direct contact between the outside air and the sample when it is disconnected from the test system, which is not conducive to the sample. for follow-up analysis

In addition, the dead volume of the sample chamber of the existing steel container is relatively large, which is likely to cause relatively large test errors

Finally, the temperature measuring thermocouple is separated from the sample chamber and placed on the outer wall of the sample chamber, which will lead to a large error in the measured reaction temperature, and will eventually affect the accuracy of the test data

Images