Industrial n-butanol (2)

4 Test method

The reagents and water used in this standard, unless other requirements are specified, use analytical reagents and distilled water or water of the same purity

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Measure according to the method specified in GB/T3143

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

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

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Measure according to the regulations of GB/T7534

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Calculate according to Chapter 6 of GB/T7534-1987, and the K value in the formula is listed in Table 2

Table 2 The rate of change of the boiling point of n-butanol with pressure (K value)

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The sample passes through the chromatographic column, and the components are separated, detected by a flame ionization detector, and quantified by area normalization
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2 Reagents and materials

a) Acetone ;

b) Polyethylene glycol 20000;

c) 101 white carrier, 0.
18～0.
25mm (80～60 mesh);

d) Nitrogen: the purity is not less than 99.
99%;

e) Hydrogen: the purity is not less than 99.
9%;

f) Air: After purification treatment
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3 Apparatus and equipment

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1 Gas chromatograph: any type of gas chromatograph whose sensitivity and stability meet the relevant regulations in GB/T9722
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2 Column

a) Column tube: stainless steel tube or glass tube with an inner diameter of 3mm and a length of 2～3m;

b) Stationary phase: polyethylene glycol 20000+101 white support = 1+10;

c) Aging of the chromatographic column: Put the filled chromatographic column into the column box of the chromatograph, and after checking the air tightness, start from the column temperature of 60°C and increase the temperature at a rate of 3°C/min, and the final temperature will reach 150°C.
Nitrogen gas is used for segmental aging, and aging at 150°C for more than 10 hours until the baseline is stable
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3 Detector: flame ionization detector
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4 Chromatographic data processor or recorder
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5 Injector: Micro syringe, 10uL
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4 Analysis steps

Adjust the instrument according to the chromatographic operating conditions.
After the baseline is stable, use a micro syringe to inject the sample, measure the peak area of ​​each component, and use the area normalization method or a data processor to calculate
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Chromatographic operating conditions, relative retention time of each component and typical chromatogram are shown in Appendix A (standard appendix)
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5 Expression of analysis results

The content of n-butanol expressed in mass percentage x _{1 is} calculated according to formula (1):

Wherein: A- sample butanol peak area;

∑A _i — the sum of the peak area of ​​each impurity in the sample;

X ₃ —The moisture content in the sample,

Take the arithmetic average of the two parallel determination results as the determination result
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The difference between the two parallel determination results shall not be greater than 0.
1%
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