Product standard and quality inspection of chloroacetic acid

8.
Product Standard

9.
Quality inspection

1) Determination of dichloroacetic acid content

Weigh about 3g of the sample in a 250mL Erlenmeyer flask, and add 50mL of 30% sodium hydroxide
.
After installing the spherical condenser, place it on a water bath and heat to reflux for 3 hours

In the formula: c——molar concentration of potassium permanganate, mol/L;

V——Volume of potassium permanganate standard solution consumed in titration, mL;

G——The mass of the sample, g
.

2) Determination of chloroacetic acid content

(1) Determination of total chlorine: Weigh about 4g of the sample (accurate to 0.
0002g), dissolve it in a 250mL volumetric flask, and add water to the mark
.
Use the pipette to accurately draw 25mL into a 250mL Erlenmeyer flask, and add 10mL of 10% sodium hydroxide

(2) Free chlorine determination: accurately draw 50mL of the above sample solution, add 2mL of nitric acid, 10mL of 0.
1mol/L silver nitrate solution, 3mL of nitrobenzene and 2mL of ferric ammonium sulfate indicator, and use 0.

In the above two formulas: c ₁ —— molar concentration of silver nitrate solution, mol/L;

V ₁ ——Volume consumed by silver nitrate solution, mL;

c ₂ ——molar concentration of ammonium thiocyanide (or sodium thiocyanate) solution, molL;

V ₂ ——Volume consumed by ammonium thiocyanide (or sodium thiocyanate) solution, mL;

G——The mass of the sample, g
.

(3) Chloroacetic acid content:

Chloroacetic acid content (%)=(AB-0.
55×C)×2.

In the formula: A——Total chlorine content, %;

B——free chlorine content, %;

C——Chloroacetic acid content, %
.

10.
Security measures

(1) When using toxic or irritating raw materials such as chlorine and acetic acid in production, the chlorination equipment should be sealed, ventilation should be strengthened in the workshop, and the operators should wear labor protection equipment
.

(2) This product is a Class II organic acidic corrosive material.
It is packaged in acid-resistant jars or iron drums lined with plastic bags.
It should be stored in a cool, ventilated and dry warehouse, away from fire and heat sources, and should be mixed with oxidants and alkalis.
Store separately
.
This product is highly toxic, irritating and corrosive.

Related links: Product performance and production principles of chloroacetic acid