Colorimetric detection of triacetin levels in cigarette filters
Triacetin is widely used as a plasticizer and one of the most important materials in cellulose acetate filter production. It is essential to check quantity of triacetin in filters because uncontrolled concentrations cause formation of melt holes or too soft filters that subsequently would lead to hot collapse effect while smoking. Traditionally triacetin levels in cigarette filter production are determined by weight comparison method but it is not very accurate, can be used only on the working production line and has other drawbacks. Our proposed method lets us determine triacetin levels in non-cured as well as fully cured filters and align the results with weight comparison method. Fast and accurate colorimetric method of triacetin determination is based on esters conversion to hydroxamic acid which forms purple-red complexes with ferric ion. This reaction is widely used in various esters determination long time. Method was specialized for triacetin detection in cigarette filters with concentrations as low as 3 x 10-4M. The experimental data showed linear relationship of calibration curve from solution concentrations in the range from 3 x 10-4M to 10-3M. We believe this practical method has the key advantages of allowing accurate determination of triacetin levels during and after the production of filters without a need for expensive equipment.