Cas 7733-02-0 ZnSO4 Zinc Salt Dyeing Mordant 161relative Molecular Mass

Product Description

The chemical formula of zinc sulfate is ZnSO4 is the most important zinc salt

Industrial use
It is the main raw material for the production of zinc barium white and zinc salts. It can also be used as a printing and dyeing mordant, a preservation agent for wood and leather, and an important auxiliary raw material for the production of viscose fibers and vinylon fibers. In addition, it has applications in the electroplating and electrolytic industries and can also be used to make cables.

Cooling water is the largest amount of water used in industry. The cooling water in the closed circulation cooling system can not corrode and scale the metal, so it must be treated. This process is called water quality stabilization, and zinc sulfate is used as a water quality stabilizer here.

Test methods
Refer to the chemical industry recommendation HG / T2326-92 Section 5.1 for the determination of the main content.

The summary of the method is as follows: ammonium chloride and potassium iodide are added to the zinc sulfate solution to eliminate the interference of impurities such as iron, and xylenol orange is used as an indicator at a pH of about 5.5, and the solution is titrated with ethylenediamine tetraacetic acid disodium standard solution.

The detailed steps are as follows:

Method name: Determination of zinc sulfate-zinc sulfate-complex titration.

Application range: This method uses complex titration to determine the content of zinc sulfate (ZnSO4 · 7H2O).

This method is suitable for the determination of zinc sulfate.

Principle of the method: Take an appropriate amount of the test sample, dissolve it in water, and use chrome black T as an indicator. Titrate with sodium diamine tetraacetic acid titration solution (0.05mol / L) until the solution changes from purple to pure blue. Each 1mL of ethylenediamine tetraacetic acid sodium titration solution (0.05mol / L) is equivalent to 14.38mg of ZnSO4 · 7H2O, which is calculated.

Reagent: 1. Water (fresh to room temperature)

2. Disodium ethylenediamine tetraacetate titration solution (0.05mol / L)

3. Reference zinc oxide

Dilute hydrochloric acid

5. Methyl red in ethanol (0.025%)

6. Ammonia test solution

7. Chrome black T indicator

8. Ammonia-ammonium chloride buffer (pH 10.0)

equipment:

Sample preparation: 1. Disodium ethylenediamine tetraacetate (0.05mol / L)

Preparation: Take 19g of disodium ethylenediamine tetraacetate, add freshly boiled cold water to 1000mL, and shake well.

Calibration: Take 0.12g of standard zinc oxide that is burned to constant weight at 800 ℃, accurately weigh, add 3mL of dilute hydrochloric acid to dissolve, add 25mL of water, add 1 drop of 0.025% methyl red ethanol solution, and dropwise add ammonia test solution to The solution is yellowish, add 25mL of water and 10mL of ammonia-ammonium chloride buffer (pH10.0), add a small amount of chrome black T indicator, titrate with this solution until the solution changes from purple to pure blue, and use the titration result with Blank test correction. Each 1 mL of ethylenediamine tetraacetic acid disodium titration (0.05 mol / L) is equivalent to 4.069 mg of zinc oxide. Calculate the concentration of this solution based on the consumption of this solution and the amount of zinc oxide taken.

Storage: Place in glass stopper bottle, avoid contact with rubber stopper, rubber tube, etc.

Dilute hydrochloric acid

Take 234mL of hydrochloric acid and dilute to 1000mL with water. This solution should contain HCl at 9.5-10.5%.

3. Ammonia test solution

Take 400mL of concentrated ammonia solution and add water to make it into 1000mL.

4. Chrome black T indicator

Take 0.1 g of chrome black T, add 10 g of sodium chloride, and grind evenly to obtain.

5. Ammonia-ammonium chloride buffer (pH 10.0)

Take 5.4 g of ammonium chloride, add 20 mL of water to dissolve it, add 35 mL of concentrated ammonia solution, and then dilute to 100 mL with water to obtain.

Operation steps: Take about 0.3g of this product, weigh it accurately, add 30mL of water to dissolve, add 10mL of ammonia-ammonium chloride buffer solution (pH10.0) and chrome black T indicator, and use ethylenediamine tetraacetic acid sodium titration solution (0.05 mol / L) Titrate until the solution changes from fuchsia to pure blue.

Note 1: "Precision Weighing" means that the weighed weight should be accurate to one thousandth of the weighed weight. "Precision Weighing" means that the accuracy of the measured volume should meet the accuracy of the volume pipette in national standards. Claim.

Note 2: "Determination of moisture" uses the drying method to take 2 to 5 g of the test sample, and spread it in a flat weighing bottle that is dry to constant weight, the thickness does not exceed 5 mm, and the loose test sample does not exceed 10 mm. Open the bottle cap and dry at 100 ~ 105 ° C for 5 hours. Cover the bottle cap, place in a desiccator, cool for 30 minutes, accurately weigh, then dry at the above temperature for 1 hour, cool, and weigh until two consecutive times. The difference in weighing does not exceed 5 mg. Calculate the moisture content (%) in the test product based on the weight lost.