SINAINT® Chromotropic acid disodium salt dihydrate

Synonym Name:Chromotropic acid disodium salt dihydrate; CHROMOTROPIC ACID DISODIUM SALT;disodium chromotropic acid;sodium 1,8-dihydroxynaphthalene-3,6-disulfonate; sodium 4,5-dihydroxynaphthalene-2,7-disulfonate dihydrate

Cas No. ：5808-22-0

Melting point: 300 ℃

Boiling point: 176-177 ℃

Flash point: 164 ℃

Molecular structure:

Spec:

Items	Standard
Appearance	Light grey to light brown powder
Assay %	≥98.5
Water soluble state	Pass
Water content %	8%一10%
Suitability of formaldehyde analysis	Pass

Application:

Biochemical research and organic synthesis. Spectrophotometric Determination of chromium, titanium and formaldehyde. Determination of chromium, mercury, silver, titanium, chlorate, formaldehyde, nitrate and nitrite. Determination of methylene dioxy by TLC. Determination of ethylene glycol in biomaterials.

Detection method

1. Purity

Potentiometric titration

Weigh 0.6g (to 0.0001g) of the dried sample, put it into a 100ml beaker, add 50ml of pure water to dissolve the sample, and titrate it with 0.1mol/l sodium hydroxide standard solution by potentiometric titrator (for determination of titration method and end point, refer to GB / T 9725)

The consumption of 0.1mol/l NaOH is 1ml, which is equivalent to 0.04003g c10h6na2o8s2 · 2H2O

2. Solubility

Weigh 5.0g of disodium chromotropic acid sample, put it in a 250ml flask, add 100ml deionized water, and stir it in a water bath at 25 ℃ for 15min. The solution is uniform and transparent by visual inspection.

3. Water content

Karl Fischer titration

4. Formaldehyde analysis

Solution A: transfer 1ml of 35% formaldehyde aqueous solution, place it in 2000ml volumetric flask, and dilute it with deionized water.

Solution B: weigh 0.0500g of disodium chromotropic acid with analytical balance, put it in a 100ml volumetric flask, and dissolve it with 70% sulfuric acid.

Turn on the constant temperature water bath, set the water temperature at 65 ℃, after preheating, transfer 2ml of solution a and 50ml of solution B into a 250ml conical flask, and heat it in the water bath. After 10-15 minutes, the solution in the conical flask turns purple.

Packaging and Shipping:

25kgs/BAG.

Storage:

Stored in a cool dry place out of direct sunlight.