Use of the double elution technique to estimate desorption efficiencies

In this preliminary work, the authors propose the use of the double elution in order to estimate the desorption efficiency of solvents collected on an active charcoal tube. An estimate of the desorption efficiency may be carried out directly on samples collected in the field by carrying out, on each of these, two successive elutions with the same CS2 volume. The technique suggested is excellent when assuming desorption efficiency rates ranging from 0.65 to 0.85; but with carbon adsorbent under study, the relationship between desorption efficiency an S₂/S₁is linear in the range 0.3 ÷ 0.9.