Zinc oxide for medical use; zinc oxide in medical protective clothing

2020-03-12

Zinc oxide for medical use; zinc oxide in medical protective clothing

Zinc Oxide Yanghuaxin

      Medical Zinc Oxide Calculated after ignition to constant weight, the content of ZnO shall not be less than 99.0%.

Properties: Zinc Oxide White to very slightly yellowish white, fine, sand-free powder; odorless; absorbs carbon dioxide slowly in air.

Insoluble in water or ethanol, soluble in dilute acids.

Identification:
(1) When the product is strongly heated, it will turn yellow. Upon cooling, the yellow color will disappear.
 
(2) Identification reaction of zinc salts in dilute hydrochloric acid solution of the product (General Rule 0301).
 
Test: Alkalinity Take 1.0 g of this product, add 10 ml of freshly boiled water, shake for 5 minutes, cool and filter. Add 2 drops of phenolphthalein indicator solution to the filtrate. 0.10 ml of hydrochloric acid titrant (0.1 mol/L), the pink color should disappear.
 
Sulfate Take 1.0 g of this product, add a suitable amount of dilute hydrochloric acid to dissolve it, and perform the test according to the method (General Rule 0802). Compared with the control solution prepared by dissolving 0.5 ml of standard potassium sulfate, it should not be deeper (0.005%).
 
Carbonate and acid-insoluble substances: Take 2.0 g Medical Zinc Oxide , mix with 10 ml of water, add 30 ml of dilute sulfuric acid, heat on a water bath, it should not foam. After stirring, the solution should be clear.
 
Loss on ignition: Take about 1.0 g of this product, weigh accurately, burn at 800 °C to constant weight. The weight loss should not exceed 1.0%.
 
Iron salts: Take Medical Zinc Oxide 0.40 g, add 8 ml of dilute hydrochloric acid, 15 ml of water and 2 drops of nitric acid, boil for 5 minutes to dissolve, cool, add a suitable amount of water to 50 ml, shake well, then take 25 ml, add 10 ml of water, check according to the method (General Rule 0807), compared with the control solution prepared from 1.0 ml of standard iron solution, it should not be deeper (0.005%).
Take 5.0 g of this product, add 24% 50% nitric acid, boil for 1 minute, cool, dilute to 100 ml, and determine by atomic absorption spectrophotometry (General Rule 2321), it should not exceed 50 ppm.
 
Arsenic salts Take 1.0 g of this product, add 5 ml of hydrochloric acid and 23 ml of water to dissolve, check according to the method (General method 0822, the first method), it should meet the requirements (0.0002%).
 

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Precautions for the use of zinc oxide in medical masks

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Rubber-grade zinc oxide