Industrial methyl chloride (5)

4.

Reagents for power moisture analyzer (commercially available reagents)

4.

4.

Add the reagents of the electricity moisture meter to adjust the electricity moisture meter to make the titration cell reach an anhydrous state

4.

Connect the injection needle with a (1～2) mm stainless steel (or suitable material) tube size connector to the sampler outlet valve of the existing sample, and insert the injection needle into the sample injection plug of the electricity moisture meter to the bottom of the titration cell , The injected sample is about 10g or adjust the sample amount according to the water content (accurate to 0.

4.

The water content X ₂ expressed in mass percentage is calculated according to formula (3):

In the formula: m ₁ -the mass of water, g;

m—the mass of the sample, g

4.

Take the arithmetic mean of the two parallel determination results as the determination result

4.

4.

Let the sample evaporate naturally, and weigh the mass of the residue

4.

4.
5.
2.
1 Evaporator: It is composed of hard glass evaporating tube, weighing tube and water bath.
The installation is shown in Figure 8
.

Figure 8 Evaporator

4.
5.
2.
2 Constant temperature drying oven: the temperature is (105±2)℃
.

4.
5.
3 Analysis steps

Dry the weighing tube in a constant temperature drying oven at (105±2)°C for about 30 minutes, move it into a desiccator to cool, weigh its mass (accurate to 0.
0002g), and connect it to the evaporation tube
.
Weigh about 500g (accurate to 1g) of the cooled non-boiling sample into the evaporation tube
.

Partially immerse the evaporator weighing tube in the water bath to evaporate the sample
.
Adjust the temperature of the water bath until the sample can evaporate for about 2 hours
.
After evaporation, wash the inner wall of the weighing tube with about 10 mL of dichloromethane , adjust the temperature of the water bath to about 90°C, and evaporate the dichloromethane
.

Remove the weighing tube from the evaporating tube, dry it in a constant temperature drying oven at (105±2)°C for about 30 minutes, put it in a desiccator to cool, and weigh its mass (accurate to 0.
0002g)
.

4.
5.
4 Expression of analysis results

The evaporation residue content X ₃ expressed in mass percentage is calculated according to formula (4):

Where: m ₀ -the mass of the weighing tube, g;

m ₁ —The mass of the weighing tube after the sample has evaporated, g;

m—the mass of the sample, g
.

4.
5.
5 Tolerance

Take the arithmetic mean of the two parallel determination results as the determination result
.
The difference between the two parallel determination results shall not exceed 0.
0003%
.

5 Inspection rules

5.
1 All items specified in this standard are type inspection items, of which purity and moisture are ex-factory inspection items
.
Under normal circumstances, type inspection shall be carried out at least once every three months
.

5.
2 The product should be inspected by the quality inspection department of the manufacturer
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The manufacturer shall ensure that all manufactured products meet the requirements of this standard, and shall be accompanied by a quality certificate in a certain format
.
The content includes: the name of the manufacturer, site, product name, grade, net content, batch number or production date and the number of this standard
.

5.
3 The user has the right to inspect the quality of the delivered products in accordance with the provisions of this standard
.

5.
4 Take products of the same quality as a batch, and the volume of each batch shall not exceed the maximum capacity of the storage tank
.

5.
5 Determine the number of sampling units and sampling volume in accordance with the provisions of 6.
6 in GB/T6678-1986
.

5.
6 The judgment of the test result shall be carried out in accordance with the comparison method of rounding value in GB/T1250
.
If one of the inspection results does not meet the requirements of this standard, samples should be taken from twice the volume of the packaging unit for re-inspection.
Even if only one indicator does not meet the requirements of this standard, the batch of products shall be judged as Unqualified
.

5.
7 The final expression of the analysis result should be consistent with the number of digits required by the technical requirements
.

6 Marking, packaging, transportation and storage

6.
1 Industrial methyl chloride products should be sealed in dry and clean liquefied gas cylinders
.

6.
2 The packaging volume of industrial methyl chloride shall be carried out in accordance with the filling standard GB14193 for liquefied gas cylinders
.

6.
3 The packaging container should be printed with a clear logo, its content includes: trademark, product name, standard number, manufacturer name, net content, in accordance with the provisions of GB190 coated with "drug" logo, in accordance with the provisions of GB/T191 coated with "Caution" Handle with care" and "Fear of heat" signs
.

6.
4 Industrial chloromethane products should be placed in a dry and ventilated place, avoid sunlight and rain
.

6.
5 The storage and transportation of industrial methyl chloride products shall comply with the relevant regulations of the People's Republic of China on the storage and transportation of dangerous goods on railways, highways and waterways
.

6.
6 Industrial methyl chloride products should not be hit during transportation and loading and unloading, and should be handled with care to avoid damage to the packaging container and product leakage
.

7 Security

Industrial methyl chloride is a toxic gas, and inhalation can cause dizziness and nausea
.
If it mixes with air or encounters high heat, the pressure in the container increases, and there is a danger of burning and explosion
.
The maximum allowable concentration of methyl chloride in the workplace is 80mg/m3
.
Operators should wear protective equipment to avoid human contact
.

In case of skin contact, rinse immediately with plenty of water; in case of inhalation, immediately leave the scene to a place with fresh air and seek medical attention
.