Arsenic dioxide salt detection device (first method Gucai method)

The device for detecting arsenic dioxide salts (first method Gu Cai's method) is designed and manufactured according to General Rule 0822 of the Pharmacopoeia of the People's Republic of China 2025 edition. It is mainly used in the food industry, as well as industrial and health inspection units for drug, food, food containers, etc. It is used for bromide test paper colorimetric method for arsenic salt inspection and determination. According to the requirements of the pharmacopoeia for the variety of silica, 20ml of heavy metal solution should be taken and 5ml of hydrochloric acid should be added. According to the first method of General Rule 0822, it should comply with the regulations (0.0003%).

1、 Main technical features

1. The design of this instrument complies with the requirements of the Pharmacopoeia of the People's Republic of China.

2. The instrument design is reasonable, the installation is simple, and the use is convenient.

3. The inner and outer test tubes are designed with a grinding mouth for easy operation.

4. This instrument is made of transparent high boron glass material, which can observe the sample well.

2、 Main principle of arsenic dioxide salt detection device (first method Gucai method)

The arsenic in the sample is precipitated with iron hydroxide and then dissolved in dilute acid. It is reduced to arsenic * by metal zinc, tin dioxide, and hydrochloric acid, and enters through the small hole of the arsenic measuring tube to react with the bromide * test paper to generate a color spot. The darker the color spot, the higher the arsenic content. Based on the standard arsenic spot with known content, the arsenic content in the sample can be measured.

The glass tube is 180mm in size, with a flat top disc and a hole in the middle. There are small hooks on both sides of the original piece for easy fastening of rubber bands as fixed caps. The caps are also polished into circular paddles and holes, and there are two semi-circular glass pieces with chicken shaped crowns on top, used to connect the upper and lower parts of the tube body. The bottom is equipped with a standard interface triangular bottle.

3、 Testing and preparation methods

During testing, 60mg of lead acetate cotton (with a height of 60-80mm) is loaded into the airway tube C. Then, a bromination test paper (the size of the test paper should cover the aperture without exposing the plane) is placed on the top surface of the plug D. The plug cover E is closed and tightened to obtain the result.

Preparation of standard arsenic spot: Accurately measure 2ml of standard arsenic solution, place it in bottle A, add 5ml of hydrochloric acid and 21ml of water, then add 5ml of iodine test solution and 5 drops of acidic stannous chloride test solution. Let it stand at room temperature for 10 minutes, then add 2g of zinc particles. Immediately plug the airway tube C, which was installed according to the above method, into bottle A, and place it in a 25-40 ° C water bath for 45 minutes. Take out the bromination test paper and obtain it.

If the test sample needs to be subjected to organic destruction before arsenic detection, a standard arsenic solution should be taken instead of the test sample, and the standard arsenic spot should be prepared according to the method specified under this variety.

Inspection method: Take the test sample solution prepared according to the prescribed methods for each variety item, place it in bottle A, and prepare it according to the standard arsenic spot. Starting from "adding 5ml of iodine * test solution", operate according to the law. Compare the generated arsenic spot with the standard arsenic spot and ensure that it is not deeper.