Device and method for detecting non-methane total hydrocarbon content and fractional hydrocarbon content of carbon dioxide

Abstract

The invention discloses a device and a method for detecting the non-methane total hydrocarbon content and the fractional hydrocarbon content of carbon dioxide. The device comprises a column box, and afirst six-port valve, a second six-port valve, a sample quantifying tube, a first chromatographic column, a second chromatographic column and an FID detector which are arranged inside the column box,wherein a port VI-a of the first six-port valve is connected with a sampled gas input pipe; a port I-a is connected with a sampled gas output pipe; a port V-a is connected to a port II-a through thesample quantifying tube; a port IV-a is connected with the carrier gas input pipe; a port III-a is connected with one end of a carrier gas output pipe; a port II-b of the second six-port valve is connected with the other end of the carrier gas output pipe; a port I-b is connected to a port VI-b through the first chromatographic column; a port V-b is connected with the FID detector; a port III-b isconnected to a port IV-b through the second chromatographic column. Through the device and the method, the non-methane total hydrocarbon content and the fractional hydrocarbon content of a sample canbe simultaneously analyzed under the conditions that an additional analytical instrument is not used and the chromatographic columns are not replaced, the operation is simple and convenient, the analysis speed is high and the analysis precision is high.

Description

technical field [0001] The invention relates to the technical field of detection of impurities in gas, in particular to a device and method for detecting the content of non-methane total hydrocarbons and sub-item hydrocarbons in carbon dioxide. Background technique [0002] Carbon dioxide gas is widely used as an indispensable resource in welding, foundry industry, fire extinguishing agent and cooling material, especially in the application field of high-purity carbon dioxide, inertness of oxidation, diffusion, chemical vapor deposition and certain reactions in semiconductor manufacturing Medium, and as raw materials such as food additives and dry ice preservation, it is also common in daily life. [0003] The method of tail gas recovery and purification purifies carbon dioxide to high-purity grade and food grade. The determination of its impurity content should be comprehensive. According to the regulations on food additive carbon dioxide in the current national food safet...

AI Technical Summary

Problems solved by technology

The determination of total hydrocarbons and the determination of sub-category hydrocarbons are relatively mature, mainly by gas chromatography. However, the qualitative and quantitative results are quickly obtained in the same chromatogram, but there is no relatively mature analysis method

At present, after analyzing non-methane total hydrocarbons, it is often necessary to manually replace the appropriate chromatographic column, while the chromatographic column for analyzing sub-category hydrocarbons is often a capillary column, and the interface is difficult to match

The other is manual sampling. The traditional six-way valve is manually performed, which is difficult to adapt to in terms of air tightness and operability.

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