Catalytic Air Freshening Diffusers Based on Isopropyl Alcohol-A Major Source of Acetone Indoors

10.4209/aaqr.2013.02.0051

Otmar Geiss；Carmen Del Cacho；Josefa Barrero-Moreno

Catalytic diffuser ； Air freshener ； Acetone,2-Methylpropanal ； IAQ

Aerosol and Air Quality Research

14卷1期（2014 / 02 / 01）

177 - 184

英文

Air fresheners are used in indoor environments for perfuming the ambience and/or masking unpleasant smells. There are several types of air fresheners on the market including those belonging to the family of catalytic diffusers. The fuel of these devices is frequently 2-methylpropanol, which, while operating, is oxidised to acetone. The acetone emission of a catalytic diffuser was measured for two fragrances under controlled laboratory conditions as well as in a private household. Emission rates were 530 mg/h and 660 mg/h respectively. Acetone concentrations of approximately 700 μg/m^3 were measured in a private household three hours after the diffuser was extinguished. Besides isopropyl alcohol, one of the two fragrances contained 2-methylpropanol as a fuel component, which is oxidised to 2-methylpropanal. The emission rate for 2-methylpropanal was 11 mg/h. Catalytic diffusers containing isopropyl alcohol as fuel were identified as being a major indoor source of acetone. Although not a legal requirement, the secondary formation of acetone should be included in product information along with a list of product constituents. As an alternative, a less easily oxidisable solvent could be used.