Methanol gasoline analysis dedicated chromatographIt is a gas chromatography instrument used for rapid, accurate qualitative and quantitative analysis of the composition of methanol gasoline (a substitute fuel mixed with a certain proportion of methanol in gasoline). It is mainly used in the fields of petrochemicals, quality inspection agencies, gas stations, and new energy fuel research and development to ensure compliance with fuel ratios, stable combustion performance, and environmental indicators.
This chromatograph is based on gas chromatography (GC) technology and is typically equipped with a dual column dual detector system: a polar capillary column (such as PEG-20M or FFAP) is used to effectively separate oxygen-containing compounds such as methanol and ethanol; Another non-polar column (such as SE-30 or DB-1) is used to analyze hydrocarbon components (such as benzene, aromatics, olefins, saturated hydrocarbons, etc.) in gasoline. The detector often uses a hydrogen flame ionization detector (FID), which is sensitive to organic compounds and has a wide linear range. Some high-end models can also integrate thermal conductivity detectors (TCD) for auxiliary analysis.
Methanol gasoline analysis dedicated chromatographThe components of:
1. Gas system:
Carrier gas: Stable and pure in nature (such as nitrogen or high-purity hydrogen with a purity of 99.999%), matched with the selected detector, used as the mobile phase to push the sample through the chromatographic column.
Gas purification device: including color changing silica gel, activated carbon, molecular sieve, etc., used to remove impurities in the carrier gas and ensure analysis accuracy.
2. Sample injection system:
Sample injector: divided into automatic and manual types, responsible for accurately and repetitively introducing the methanol gasoline sample to be tested into the chromatographic column.
Special injection ports: Some models are equipped with packed column injection ports (with spacer blowing, which can be connected to large-diameter capillary columns), split/non split capillary injection ports, etc., to meet different analysis needs.
3. Separation system:
Chromatography column: a core separation component, divided into two types: packed column and capillary column (open tube column). Column materials include metal, glass, fused quartz, polytetrafluoroethylene, etc.
Pre cut column and analytical column: Pre cut column is used to vent light hydrocarbons or non target components, while analytical column is responsible for separating target compounds (such as alcohols, ethers, aromatics, etc.). For example, pre cut columns may use 0.56m × 0.38mm stainless steel columns with 20% TCEP/Chromosorb P (AW) 80-100 mesh inside; The analysis column may use a 30m × 0.32mm × 3 μ m cross-linked methyl silicone quartz capillary column.
4. Detection system:
Detector: Convert the concentration or mass (content) of each component separated by a chromatographic column into an easily measurable electrical signal (such as voltage, current, etc.).
Common detector types: hydrogen flame ionization detector (FID), thermal conductivity detector (TCD), flame photometric detector (FPD), nitrogen phosphorus detector (NPD), etc. Among them, FID detectors are widely used in methanol gasoline analysis due to their high sensitivity and wide linear range.
5. Temperature control system:
Temperature control components: mainly used for precise temperature control of the gasification chamber, chromatographic column, and detector.
Temperature control range and accuracy: The temperature control range usually covers room temperature+5 ℃ to 450 ℃, and the temperature setting accuracy can reach 0.1 ℃ to ensure separation efficiency and detection stability.
6. Data processing system:
Workstation or software: Record and analyze detection signals, generate chromatograms and quantitative results.
Functional features: Some workstations have functions such as automatic measurement of chromatographic peak area, direct provision of accurate quantitative analysis data, and automatic reprocessing and analysis of chromatographic analysis data. In addition, it can directly calculate the expression forms of various national standard requirements such as volume fraction, mass fraction, volume percentage, and mass percentage, and has density conversion function.