Home > News > Content
PSA N2 Generator Improve The Electrolysis Efficiency
Oct 09, 2017

The PSA N2 Generator is a set of equipment that can extract nitrogen. It is mainly used in the fields of aerospace, nuclear nuclear power, food medicine, petrochemical industry, electronics industry, material industry, national defense industry and scientific experiment. In order to understand the status quo, the following I have introduced several applications in the gas chromatography analysis of PSA N2 Generator principle, for your reference.

1, electrochemical method of nitrogen;

2, using hollow fiber membrane separation method;

3, PSA pressure swing adsorption nitrogen.

The use of electrochemical method of PSA N2 Generator can be made of pure nitrogen, oxygen and other gases. It uses a constant potential electrolysis method, the use of microporous membrane (such as asbestos film) as the separation of two electrodes, porous gas diffusion electrode for the cathode, nickel mesh for the anode, and the electrode is installed using a hard support structure. The generator can be nitrogen, oxygen chamber pressure (1MPa) under the stable operation, to avoid cathodic hydrogen precipitation, to ensure the purity of nitrogen gas. The specific method of making nitrogen is to feed the gas into the electrolytic cell with air as the raw material. Between the two electrodes, the DC voltage of ≤1.5V is applied. At this time, oxygen is absorbed in the air in the tank to obtain nitrogen. The electrolyte with "forced circulation" by the electromagnetic pump to promote the electrolyte in the liquid circulation, improve the electrolysis efficiency.

This method can produce up to 99.995% of the nitrogen, but there are several obvious defects: First, the need to use a high concentration of potassium hydroxide solution as electrolyte, this strong alkali solution and gas in direct contact with the gas quality The third part of the reaction process only to remove the oxygen in the air, and other impurities are not involved in the gas, and the other is not suitable for the large flow of PSA N2 Generator; The reaction process of the electrolytic cell production technology requirements are high, inappropriate electrolytic cell production technology will result in the order of nitrogen purity reduction. However, such PSA N2 Generators, as a source of small flow of nitrogen, are often used for chromatographic carrier gas and small capacity protection, the total cost of a few thousand dollars, is a low-cost solution.

The relative permeation rate of the gas in the membrane is different. According to this feature, the gas can be divided into "fast gas" and "slow gas".

When the mixed gas is driven by the pressure difference between the driving force and the membrane, the gas with relatively high permeation rate and water, oxygen, carbon dioxide and so on are permeated on the membrane permeation side and the permeation rate is relatively slow Gas such as nitrogen, carbon monoxide, argon, etc. are concentrated in the retention side, so as to achieve the purpose of mixed gas separation.

When pressurized air is used as the gas source, inert gases such as nitrogen are enriched into high purity for production applications, and oxygen-enriched air is emptied from the permeate side. Nitrogen film system can be low in the air from 78% to 95%, up to 99.9% of pure nitrogen.

This method of nitrogen separation of membrane nitrogen in the industry has a lot of applications in the laboratory is mainly used for gas purity requirements are not particularly high purging, protection, replacement of oxygen and so on. The main advantages of this type of generator is the flow of large, while long life, and maintenance costs are very low; the disadvantage is that nitrogen purity can not achieve high purity, membrane components are currently imported, domestic can not provide high cost, instrument prices are relatively high.

The use of nitrogen and other gas molecules in the molecular sieve adsorption capacity difference, the formation of the concentration difference in the accumulation of molecular sieve column end of the output of high purity nitrogen. At the same time the use of two molecular sieve column, a suction at the same time leads to a part of the product gas for another analysis, to achieve molecular sieve online regeneration, the overall performance of the instrument is the continuous output of high purity nitrogen.

This type of generator can adjust the purity and flow rate of nitrogen according to the needs, the highest production of 99.999% of nitrogen products, the flow can be from several hundred milliliters to tens of liters to several cubic per minute, the purity of the configuration flexibility, according to each demand Specific customization, suitable for a variety of gas chromatography detector.

As described above, the PSA N2 Generator using the PSA pressure swing adsorption nitrogen technology is superior to the PSA N2 Generator using the electrochemical separation method and the physical adsorption method and the hollow fiber membrane method. It can be used at home and abroad for a variety of different types of gas chromatograph used as a carrier gas, is a good performance, easy maintenance of a new generation of PSA N2 Generator, with the world's leading level.