Factors affecting gas purity
The purity requirement for the gas source used in capillary ion chromatography must be above 99.99%, but many operators do not pay enough attention to the situation where different gas source purities are required for different gas chromatography detectors. In use, it is possible that the baseline and height limit of capillary ion chromatography may be unstable due to insufficient purity of the gas source. For example, using hydrogen gas with a purity of 98% as the gas source for the detector, when used in the 104M Ω sensitivity range of the detector, the detection baseline may be severely unstable due to insufficient hydrogen purity, as if there are never-ending peaks displayed. When the purity of the carrier gas is not high and contains trace amounts of oxygen, it will affect the service life of the capillary column.
Factors influencing the selection of airflow ratio
When using a detector to analyze samples, it is necessary to ignite the N2-H2 Air flame and convert it into an oxygen rich flame, that is, the air should be excessive to ensure the combustion of hydrogen *. The ratio of the three gases should be Air: H2=(6-8): 1, N2: H2=1: (0.85-1), or the amount of air should be larger. Under these conditions, the stability and sensitivity of capillary ion chromatography are high, ensuring the reliability of the quantitative calibration factors produced.
Factors of environmental conditions
The requirements for the temperature environment of the chromatograph are not special. Generally, it can meet the operating requirements at room temperature of 5-35 ℃. For humidity environments, it is recommended to be between 20% and 85%. In areas with high humidity, when using certain models of chromatography instruments, the insulation performance of the instrument may decrease due to high environmental humidity. If the response value is operated in high sensitivity mode, it will decrease. The staff should take necessary measures when encountering the above phenomenon while using a capillary ion chromatograph. Environmental conditions for use: relative humidity:<85%, working environment temperature: 15-30 ℃, power supply voltage: 220 ± 10%, should be equipped with a smooth and flat workbench.