Isobutyl acetate for industrial use (2)

4 Test method

4.

Carry out according to the method specified in 3.

4.

Carry out according to the method specified in 3.

In the range of the isobutyl ester content of 99.

4.

Carry out according to the method specified in 3.

4.

Carry out according to the method specified in 3.

When the water content is between 0.

4.

Carry out according to the method specified in 3.

When the acidity is between 0.

4.

4.

Use ethanol as a solution to promote the dissolution of the indicator solution in the sample, and use political red acid as the indicator solution to titrate with the sodium oxychloride standard titration solution .

4.
5.
2.
2 Reagents

4.
5.
2.
2.
1 Ethanol: 0=95%
.

4.
5.
2.
2.
2 Sodium hydroxide standard titration solution: c(NaOH)=0.
02 mol/L
.

4.
5.
2.
2.
3 Rose red acid indicator solution: 1g/L
.

4.
5.
2.
3 Instruments

Burette: 10mL, the sub-scale is 0.
05mL
.

4.
5.
2.
4 Test procedure

Measure 20 mL of ethanol in an Erlenmeyer flask, add 2 drops of rosonic acid indicator solution, shake well, and titrate with sodium hydroxide standard titration solution until the solution turns pink
.
Use a pipette to transfer 20 mL laboratory samples, shake well, and titrate with a standard titration solution of sodium hydroxide until the solution turns pink
.
Record the volume of sodium hydroxide standard titration solution consumed by the sample
.

4.
5.
2.
5 Result calculation

The acidity is calculated as the mass fraction w ₁ of acetic acid (CH ₃ COOH) , and the value is expressed in %, calculated according to formula (1):

Where:

V— The value of the volume of the standard titration solution (4.
5.
2.
2.
2) of sodium hydroxide consumed by the sample , in milliliters (ml);

c—The exact value of the concentration of sodium hydroxide standard titration solution, the unit is moles per liter (mol/L);

M—The value of the molar mass of acetic acid, in grams per mole (g/mol) (M=60.
1);

V ₁ —The value of the volume of the sample, the unit is milliliters (mL);

p _t —The value of the density of the laboratory sample when the temperature t is measured, in grams per milliliter (g/mL)
.

When the acidity is between 0.
0027% and 0.
013%, the estimated value s _r of the standard deviation of the repeatability test is 0.
0012%, and the repeatability limit r is 0.
0033%
.

4.
6 Determination of chromaticity

Carry out according to the method specified in 3.
1 of GB/T127172007
.