Product Overview

1. Impurity Filtration: It can effectively intercept solid particles in the gas, such as dust and sand, preventing them from entering gas sensors or subsequent analytical instruments and avoiding clogging or damage to components.
2. Moisture Separation: During gas transmission, it can separate moisture (e.g., water droplets) contained in the gas, ensuring the dryness of the gas source, and preventing performance degradation of pneumatic components as well as corrosion and damage to gas sensors.
3. Oil Mist Removal: For gas sources containing oil mist in some specific environments, the gas sampling filter can remove oil mist through special materials and structures, keeping the gas source clean and avoiding impact on the sensitivity and accuracy of gas sensors.
4. Reduction of Cross-interference: It can filter out interfering gases and reduce gas cross-sensitivity, avoiding the situation where electrodes in the sensor react even when the target gas is not present in the environment, thus ensuring accurate readings of gas detectors.
5. Equipment Protection: As the first barrier to protect gas sensors and sampling pumps, it filters out corrosive gas media and extends the service life of equipment.

Working Principle

1. Interception Filtration: It directly intercepts particulate impurities in the gas through physical means such as filter screens and filter membranes, and blocks solid particles of different particle sizes from passing through according to the pore size of the filter screens or membranes.
2. Adsorption Filtration: It uses adsorptive materials such as activated carbon to adsorb impurity gases and organic solvents in the gas. Activated carbon has a well-developed internal pore structure and a large specific surface area, enabling it to adsorb a variety of harmful gases.
3. Chemical Reaction Filtration: It adopts highly oxidizing materials such as alumina/sodium oxide to react with reducing gases in the gas through oxidation, decomposing them and thus removing specific gas impurities. It has a high removal efficiency for NO₂, B₂H₆, SiH₄ and acidic gases (such as HCl), etc.
4. Hydrophobic and Breathable Filtration:

   Filter membranes or filter elements made of hydrophobic materials such as polytetrafluoroethylene (PTFE) only allow gas to pass through while blocking liquids such as moisture, achieving the effect of gas-liquid separation. At the same time, some waterproof and breathable membranes can play a similar role, ensuring the normal passage of gas while filtering moisture.

Filter Element Materials

1. Polytetrafluoroethylene (PTFE) Filter Element: Polymerized from tetrafluoroethylene and made into membrane materials through special processes. It has strong hydrophobicity, non-adhesion, corrosion resistance, thermal stability and good mechanical properties, can effectively intercept dust particles in the air, and has a long service life.
2. Activated Carbon Filter Element: Made of carbon-containing materials, it has a well-developed internal pore structure, a large specific surface area and strong adsorption capacity, and is often used to remove impurity gases, organic solvents and isopropanol in the air in the environment.
3. Alumina/Sodium Oxide Filter Element: Utilizing its strong oxidizing properties, it oxidizes and decomposes reducing gases in the gas, has a high removal efficiency for a variety of harmful gases, and is suitable for the detection of specific gases.
4. Cellulose Filter Element: Derived from natural cellulose materials, it retains the excellent properties of natural cellulose such as mechanical strength, solvent resistance and thermal stability, and can be used to eliminate the influence of specific gases such as HF.
5. Photocatalyst Filter Element: It uses photo-semiconductor materials represented by nano-sized titanium dioxide, which produce strong catalytic degradation functions under the action of ultraviolet and visible light, and can be used to remove gases such as NOₓ, SOₓ and HF.

Application Fields

1. Environmental Monitoring: Used for on-line determination of atmospheric particulate matter, grid monitoring of air quality, etc., helping to monitor the concentration of pollutants in the air and understand the air quality status.
2. Industrial Production: In industries with strict air quality requirements such as microelectronics, coating, food and beverage, it can monitor changes in air quality during the production process, timely detect and solve air pollution problems, and ensure the cleanliness of the production environment and the health of employees.
3. Chemical, Oil Refining and Other Industries: It can filter impurities and corrosive gases in the gas generated during the production process, protect gas detection instruments, and provide accurate data support for the control and optimization of the production process.
4. Pharmaceutical Field: In the pharmaceutical production process, it is used to filter microorganisms, particles and other impurities in the air to ensure the cleanliness of the pharmaceutical production environment; in breathing equipment, it can filter particles in the gas inhaled by patients to prevent cross-infection of the respiratory system.
5. Scientific Research: Used for sampling and filtration of various gas experiments in laboratories to ensure the accuracy and reliability of experimental results.

Selection Considerations

1. Filtration Precision: Select the appropriate filtration precision according to the size of the impurity particles to be filtered. For example, for occasions requiring filtration of extremely fine dust, filter membranes or screens with smaller pore sizes may be needed.
2. Material Compatibility: Consider the material compatibility of the filter with the contacted gas, sampling equipment and subsequent analytical instruments to avoid chemical reactions or corrosion. For example, when handling corrosive gases, filters made of corrosion-resistant materials such as polytetrafluoroethylene should be selected.
3. Flow Requirements: Select a filter that can meet the corresponding flow rate according to the flow demand of gas sampling to ensure the smooth progress of the sampling process without affecting the sampling efficiency due to the limitation of the filter.
4. Working Pressure and Temperature: Select a filter that can withstand the corresponding pressure and temperature range according to the actual pressure and temperature conditions of the working environment to prevent the filter from being damaged due to excessive pressure or temperature during use.
5. Cost Factors: On the premise of meeting the use requirements, comprehensively consider the purchase cost, replacement cost and maintenance cost of the filter, and select a product with high cost performance.