Gibson, Lorraine and Littlejohn, David (1997) Determination of experimental diffusion coefficients of acetic acid and formic acid vapours in air using a passive sampler. Analytica Chimica Acta, 341. pp. 1-10. ISSN 0003-2670Full text not available in this repository. (Request a copy from the Strathclyde author)
Apassive sampling method has been developed for aceticacid and formicacidvapours in ambient air. The procedure involves collection of the vapours in a Palmes diffusion tube (7.1 cm long and 1.1 cm i.d.) and analysis by ion chromatography. Application of Fick's first law of diffusionallows calculation of the acidvapour concentrations. To validate the procedure, the tubes have been exposed to calculated or known concentrations of aceticacid and formicacidvapours, so that the diffusioncoefficients of each acid can be calculated for comparison with theoretical values. Two procedures were used to generate acidvapour concentrations in the range 6–26 mg m−3. Solutions containing calcium chloride and aceticacid or formicacid were placed in desiccators in which replicate diffusion tubes were exposed. The derived diffusioncoefficients of aceticacidand formicacid were 0.110 ± 0.003 and 0.127 ± 0.005 cm2s−1, respectively. An alternative procedure used a 43 dm3 exposure chamber and acidpermeation devices to produce the acidvapour concentrations. The experimentally derived diffusioncoefficients obtained with this system were 0.133 ± 0.007 and 0.120 ± 0.008 cm2s−1 for aceticacid and formicacidvapours, respectively. The theoretical diffusioncoefficients for aceticacid and formic acid vapours are 0.105 and 0.129 cm2 s−1, respectively.
|Keywords:||passive sampling; , ion chromatography, acetic acid, ambient monitoring, formic acid , diffusion coefficients , palmes tube, Chemistry, Biochemistry, Spectroscopy, Environmental Chemistry, Analytical Chemistry|
|Subjects:||Science > Chemistry|
|Department:||Faculty of Science > Pure and Applied Chemistry|
|Depositing user:||Pure Administrator|
|Date Deposited:||09 Nov 2011 11:36|
|Last modified:||02 Sep 2016 02:49|