Method for detecting arsenic content in water body

Abstract

The invention provides a method for detecting an arsenic content in a water body. The method comprises the following steps of: a) providing a sample to be detected, and mixing protonic acid with the sample to be detected containing hydrogen sulfide, so that the protonic acid and sulfide in the sample to be detected are reacted to generate the hydrogen sulfide; b) introducing air into the sample to be detected containing hydrogen sulfide, and removing hydrogen sulfide; c) mixing a reducing agent with the sample to be detected, so that an arsenious compound is reduced to be arsenic hydride; and d) absorbing arsenic hydride by using an absorbent and carrying out chromogenic reaction, detecting developed liquid through a spectrophotometry, and obtaining content of an arsenic element in the water body through calculation. The detection method provided by the invention not only can be used for effectively removing sulfide interference but also is environmentally-friendly and easy to operate. The invention further provides a device for detecting the arsenic content in the water body.

Description

technical field [0001] The invention relates to the field of chemical detection and specifically designs a method for detecting arsenic content in water bodies. Background technique [0002] Arsenic is a ubiquitous pollutant in water bodies, and the World Health Organization believes that long-term drinking of water containing more than 10 milligrams of arsenic per liter can lead to arsenic poisoning, a chronic disease that causes skin disorders, gangrene and cancer of the kidney and bladder . Arsenic in water is usually present in the form of arsenate and arsenite. Since arsenic and phosphorus are in the same family and have similar properties, the direct analysis of arsenic is greatly interfered by phosphorus. The most effective method is to reduce arsenic to arsine hydrogen (AsH 3 ) to be separated, generally using potassium borohydride or zinc as reducing agent, taking trivalent arsenic as an example, the reaction is as follows: [0003] As 3+ +3Zn+6H + →2AsH 3 +3Z...

AI Technical Summary

Problems solved by technology

This method has two main disadvantages: ① not only the unobstructed air, but also the full contact of hydrogen sulfide air and lead acetate cotton must be considered, and the tightness of the lead acetate cotton is difficult to adjust; ② the lead sulfide waste produced in the experiment contains certain environmental toxicity, which is difficult to deal with

US 2002 / 0000414A1 uses a strengthened oxidant to oxidize sulfide to sulfate, and then adds organic amines to eliminate excess strong oxidant. This method has a complicated process and the reagents used are highly toxic.

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