Industrial Isobutanol (2)

4 Test method

The reagents and water used in this standard, unless other requirements are specified, are analytical reagents and tertiary water that meets the requirements of GB/T6682

The standard solutions, preparations and products used in this standard shall be prepared in accordance with GB/T601 and GB/T603 when other requirements are not specified

4.

Carry out according to the method specified in GB/T3143

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

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Carry out according to the regulations in 2.

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

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Use capillary column or packed column gas chromatography to separate the components in the sample under selected working conditions, detect with flame ionization detector, and calculate the content of isobutanol with calibration area normalization method

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6 Auxiliary gas: nitrogen, with a purity of not less than 99.
9%
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7 Combustion gas: air, after purification treatment
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3 Apparatus and equipment

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1 Gas chromatograph: All gas chromatographs that can meet the operating conditions of capillary column or packed column listed in Table A1 can be used
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2 Detector: flame ionization detector
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3 Chromatographic column:

a) The recommended chromatographic columns, chromatographic operating conditions, relative retention time, relative correction factors and typical chromatograms of this standard are shown in Appendix A (standard appendix)
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Among them, capillary column gas chromatography is the arbitration method
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Chromatographic columns and chromatographic operating conditions that can achieve the same degree of separation can be used
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b) The aging of the packed column is to load the packed chromatographic column into the column box of the chromatograph.
After checking the air-tightness, start from the column temperature of 60°C and increase the temperature at a rate of 3°C/min.
The final temperature reaches 150°C.
Nitrogen staged aging, aging at 150°C for more than 10 hours, until the baseline is stable
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4 Recorder, integrator or chromatographic data processor
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5 Micro sampler: 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-injector to inject the sample, measure the peak area of ​​each component, and calculate it with the corrected area normalization method
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5 Expression of analysis results

The isobutanol content X ₁ expressed in mass percentage is calculated according to formula (1):

In the formula: A—the peak area of ​​isobutanol;

f — The relative correction factor of isobutanol ;

A _i —the peak area of ​​component i;

f _i — relative correction factor of component i;

∑(A _i f _i )—the sum of the corrected bee area of ​​all components;

X ₃ —The moisture measured by 4.
6
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Take the arithmetic mean of the two parallel determination results as the determination result
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The difference between the two parallel determination results shall not exceed 0.
1%
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4 Determination of acidity

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1 Method summary

Using phenolphthalein as an indicator, use sodium hydroxide standard titration solution to determine the acidity of the sample
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2 Reagents and materials

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1 Ethanol : 95%
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2 Phenolphthalein indicator: 10g/L
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3 Sodium hydroxide standard titration solution: c(NaOH)=0.
05mol/L
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Related Links: Isobutanol for Industrial Use (1)