Gas chromatograph is an instrument used to analyze the composition of gases, which is widely used in environmental protection, chemical industry, food, medicine and other fields. The following are the operating steps and data interpretation of the gas chromatograph:
1. Operation steps:
1.Prepare the sample: The gas sample to be measured is collected with a gas sampling bag or sampling bottle, and the sampling time and volume are recorded.
2.Power on: Turn on the power of the gas chromatograph and wait for the instrument to stabilize.
3.Set parameters: Set the corresponding chromatographic parameters, such as carrier gas type, flow rate, detector type, temperature, etc., according to the composition of the gas to be measured and the instrument model.
4.Injection: The collected gas sample is injected into the inlet through a syringe or continuously analyzed by means of a ** sampling device.
5.Start the analysis: Start the chromatograph and wait for the chromatographic peaks to appear.
6.Data analysis: Analyze the type and concentration of gas components based on chromatograms and data**.
7.Result processing: The analysis results are processed, such as calculating the percentage content of each component, drawing curves, etc.
8.Clean: Wipe the inlet and column with clean gauze to keep the instrument clean.
9.Power off: Turn off the power of the gas chromatograph and end the experiment.
2. Data interpretation:
1.Chromatogram: A chromatogram is a graph of time abscissa, peak height, or peak area as the ordinate. Each peak represents a gas component, and the peak height or peak area reflects the concentration of that component.
2.Peak identification table: Based on the peaks in the chromatogram, different gas components can be identified. By comparing with a standard sample or using known information, the composition of each peak can be determined.
3.Quantitative: Based on the peak height or area in the chromatogram, the concentration of each gas component can be calculated. Quantitative calculations are usually performed using either the internal or external standard method.
4.Data analysis result table: Organize the results of quantitative calculation into ** form, including gas composition type, concentration range, average concentration and other information. Depending on the actual needs, you can also draw the corresponding curve chart or bar chart.
5.Interpretation of results: According to the data analysis results table and charts, the content and distribution of each component in the gas to be measured can be interpreted. For example, the main components, the types and amounts of impurities can be determined. At the same time, it can also be compared and analyzed between different samples, such as concentration trends, composition differences, etc.
6.Application example: Gas chromatograph can be used in the field of environmental protection for air quality monitoring, composition analysis of exhaust gases, etc.;In the chemical field, it can be used for mixed gas analysis, product quality control, etc.;In the field of food and medicine, it can be used for ingredient testing, quality control, etc. Selecting the appropriate gas chromatograph model and parameter settings according to actual needs can provide accurate and reliable data support for research and applications in related fields.