Air quality—Determination of formaldehyde—
Acetylacetone spectrophotometric method
1 Subject content and applicable scope
1.1 Subject content
This standard specifies acetylacetone spectrophotometric method for determination of formaldehyde in industrial waste gas and ambient air.
1.2 Application scope
1.2.1 This method is applicable to the determination of the exhaust gas discharged from resin manufacturing, coating, artificial fiber, plastic, rubber, dyestuff, pharmaceutical, paint, leather and other industries, as well as the formaldehyde vapor produced during medical disinfection, corrosion prevention and fumigation.
1.2.2 When the sampling volume is 0.5–10.0L, the determination range is 0.5–800 mg/m3.
1.2.3 When the formaldehyde concentration is 20 μg/10 ml, 8 mg phenol (400 times), 10 mg acetaldehyde (500 times) and 600 mg ammonium ion (30,000 times) coexisted without interference; SO2 coexisted is less than 20 μg, NOx coexisted is less than 50 μg, and the recovery rate of formaldehyde is not less than 95%.
2 Principle
After the formaldehyde gas is absorbed by water, it reacts with acetylacetone in the acetic acid-ammonium acetate buffer solution with pH = 6. Under the boiling water bath condition, a stable yellow compound is rapidly formed and measured at the wavelength of 413 nm. The reaction formula is as follows:
Foreword i
1 Subject content and applicable scope
2 Principle
3 Reagents
4 Instruments
5 Sample
6 Procedure
7 Expression of results
8 Precautions
Additional Explanation
