Method for purifying acetonitrile for liquid chromatogram-mass spectrometer

Abstract

The invention discloses a method for purifying acetonitrile for a liquid chromatogram-mass spectrometer. The method is characterized in that impurities in a raw material acetonitrile are removed through procedures such as modified activated carbon adsorption, and thus acetonitrile for the liquid chromatogram-mass spectrometer can be obtained. By adopting the method for purifying acetonitrile for the liquid chromatogram-mass spectrometer, acetonitrile of which the purity is greater than or equal to 99.99% (wt) can be obtained, the requirements of the liquid chromatogram-mass spectrometer on high purity can be met, the purified acetonitrile can be applied to the field of liquid chromatogram-mass spectrometers, and the application range is widened.

Description

technical field [0001] The invention relates to the field of solvent purification, in particular to a method for purifying acetonitrile for liquid chromatography-mass spectrometry. Background technique [0002] Online chromatography-mass spectrometry combines the separation power of chromatography with the qualitative capabilities of mass spectrometry, enabling more accurate quantitative and qualitative analysis of complex mixtures. It also simplifies the sample pretreatment process and makes the sample analysis easier. Chromatography-mass spectrometry includes gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry, LC-MS and GC-MS complement each other to analyze compounds of different properties. [0003] Liquid Chromatograph Mass Spectrometer, or LC-MS for short, is a high-end instrument in the organic analysis market. Liquid chromatography (LC) can effectively separate the organic components in the samples to be tested, while mass spectrometry...

AI Technical Summary

Problems solved by technology

As a mobile phase solvent, the higher the purity, the better the separation effect of organic matter in the sample, and the high-purity solvent can avoid the phenomenon of insufficient ionization of the analyte caused by the existence of impurities, especially metal ions. In the mass spectrometry analysis, it complexes with the measured substance and produces interference peaks in the mass spectrometer, which leads to misjudgment of the determination of molecular weight and other parameters, and greatly reduces the accuracy of the liquid chromatography-mass spectrometry measurement results

[0004] As a solvent with excellent performance, acetonitrile can dissolve various organic, inorganic and gaseous substances, but its purification is very difficult

Because industrial acetonitrile is made from petrochemical products, the product contains many organic impurities such as heterocyclic aromatic hydrocarbons containing carbon-carbon double bonds. Their boiling range is only a few degrees different from that of acetonitrile. , such as high solubility and the ability to form an azeotropic system with many organic substances, although the impurities are very small, because there are many azeotropic systems, it is difficult to remove the above impurities even with very good rectification equipment

On the other hand, the traditional acetonitrile purification process does not have a special process for removing metal ions, so that the content of metal ion impurities in acetonitrile is relatively high

Therefore, it is difficult to achieve acetonitrile that meets the high purity requirements of liquid chromatography-mass spectrometry through existing purification techniques.