Technical improvement research and development method of extracting agent for measuring phosgene in air

Abstract

The invention discloses a technical improvement research and development method of an extracting agent for measuring phosgene in air, the method is used for researching different extracting agents capable of dissolving 1, 3-diphenylurea and the absorbance value of the extracting agent at the wavelength of 257nm by using various ultraviolet spectrophotometers on the basis of precise measurement of phosgene. The invention aims to realize the universality of an extracting agent which does not need to be subjected to acid pickling and distillation in phosgene determination under a domestic ultraviolet spectrophotometer. The invention relates to the technical field of environment. According to the technical improvement research and development method of the extracting agent for measuring phosgene in air, the extracting agent without acid pickling and distillation processes is adopted for measuring phosgene in air through an ultraviolet spectrophotometric method, and domestic ultraviolet spectrophotometers produced by different manufacturers are adopted for measuring a calibration curve; and the complexity and danger of extracting agent preparation and the harsh requirement on an ultraviolet spectrophotometer in the traditional method for measuring phosgene by aniline ultraviolet spectrophotometry are avoided.

Description

technical field [0001] The invention relates to the field of environmental technology, in particular to a research and development method for technical improvement of an extractant for measuring phosgene in air. Background technique [0002] Phosgene, also known as carbonyl chloride, is highly toxic and is one of the high-temperature pyrolysis products of chloroplastics. It is used as an intermediate in organic synthesis, pesticides, drugs, dyes and other chemical products. Aliphatic chlorocarbons (such as chloroform, trichloroethylene etc.) can produce phosgene when burning. Currently, commonly used phosgene determination methods in the air include "Determination of Phosgene in Stationary Pollution Source Exhaust by Aniline Ultraviolet Spectrophotometry", "Determination of Toxic Substances in Workplace Air Acid Halide Compounds", The determination principles of the two methods are the same, phosgene is absorbed by aniline solution to generate 1,3-diphenylurea, extracted wit...

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Problems solved by technology

[0002] Phosgene, also known as carbonyl chloride, is highly toxic and is one of the high-temperature pyrolysis products of chloroplastics. It is used as an intermediate in organic synthesis, pesticides, drugs, dyes and other chemical products. Aliphatic chlorocarbons (such as chloroform, trichloroethylene etc.) can produce phosgene when burning. Currently, commonly used phosgene determination methods in the air include "Determination of Phosgene in Stationary Pollution Source Exhaust by Aniline Ultraviolet Spectrophotometry", "Determination of Toxic Substances in Workplace Air Acid Halide Compounds", The determination principles of the two methods are the same, phosgene is absorbed by aniline solution to generate 1,3-diphenylurea, extracted with a solvent under acidic conditions, and the absorbance is measured at a wavelength of 257nm, and its value is proportional to the phosgene content. The n-hexane, dichloromethane, and isopropanol in the extractant used (n-hexane, methylene chloride, and isopropanol are mixed in a volume ratio of 1+1+0.2) must be pickled and distilled. The process is complicated and dangerous, and Many analysts have responded that the two methods cannot pass through the light at a wavelength of 257nm when measured by some domestic ultraviolet spectrophotometers.

[0003] In the prior art, when phosgene is measured by aniline ultraviolet spectrophotometry, it is a purification extractant, and a large amount of sulfuric acid pickling and distillation are used to determine the high cost and high risk of phosgene samples brought by electricity.

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