Instrument and method for detecting soluble organic nitrogen

Abstract

The invention relates to an instrument and method for detecting soluble organic nitrogen. The instrument comprises an end injection valve, a chromatographic column, a decompression valve, an acid injection valve, an oxygen injection valve, an acid-oxygen reaction spiral pipe, a UV digester, a buffering solution injection valve, a buffering solution reaction spiral pipe, a cadmium column, a color developing agent injection valve, a color developing agent reaction spiral pipe and a UV detector which are successively connected with one another by virtue of a pipeline, wherein the end injection valve is used for receiving a flowing phase and a sample, and the UV detector is connected with a computer for processing data. A dimensional exclusion chromatographic column is used for separating different molecular weight components in a water sample, then the ultraviolet rays and oxygen fluid are used for oxidation, the DON of components in different molecular weight intervals is oxidized into nitrate nitrogen. The content of nitrite nitrogen obtained in a reduction manner in the outlet water is detected by using a N-ethylenediamine spectrophotometric method, and then the DON concentration in the water sample is obtained in a calculation manner. Compared with the prior art, the instrument and method provided by the invention can realize the automatic operation in the whole course, and isfewer in errors and short in analysis time.

Description

technical field [0001] The invention relates to the technical field of environmental detection, in particular to an instrument and method for detecting dissolved organic nitrogen. Background technique [0002] Nitrogen exists in the atmosphere mainly in the form of simple nitrogen in nature, and the content in the crustal soil is very small. Nitrogen in the atmosphere enters the soil mainly through two forms of "nitrogen fixation". One is through lightning and other actions to convert nitrogen in the atmosphere into nitrogen-containing compounds, and enter the soil with rainfall; the other is through microorganisms. "Nitrogen fixation", that is, to fix nitrogen in the atmosphere in plants to form nutrients, which facilitate the absorption and growth of plants. Consumers directly or indirectly feed on plants and convert organic nitrogen in plants into organic nitrogen in animals. Nitrogen, and finally nitrogen enters the soil in the form of remains or excretions of plants an...

AI Technical Summary

Problems solved by technology

This method does improve the accuracy of DON concentration detection, but it takes a long time to detect DON concentration, the detection efficiency is low, and the operation in the detection process is complicated. These shortcomings are also the common problems of most methods for detecting DON concentration at home and abroad.

The difference method is usually used to detect the concentration of DON in the laboratory. There are two kinds of total nitrogen minus inorganic nitrogen and total Kjeldahl nitrogen minus ammonia nitrogen. , has a greater impact on the results

These methods for detecting DON concentration can no longer meet the requirements for rapid and accurate detection of DON concentration

Similarly, most of the instruments currently on the market can only detect the concentration of TN and ammonia nitrogen, and the detection of DON concentration is also based on the difference method similar to laboratory detection, for example: the TN analyzer of WTW in Germany. The detection of DON concentration is also carried out by using the above-menti

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