Tobacco Documents Online

Copy for Dr. S. J. Greeff - for M. P. D. Cj • HGH/JP/46B-II NITRIC OXIDE FILTRATION PROJECT 7th J.une, 1975 . i .......... 19LE ...... The current project on the filtration of nitric oxide is aimed at discovering filter ~dditives which will reduce the delivery of nitric oxide from cigarettes. The materials evaluated so far fall into two groups - those which are commer- cially available at present and those which can be made in the laboratory from commercially available substances. So far, some 50 materials have been evaluated, some of them at several different levels. Commercially Available Materials All materials in this classification which have been evaluated are activated carbons. We have evaluated i0 such materials in filters containing 100mg of carbon. The most effective carbons found so far are: HCN-NO selective (ex Pittsburgh Carbon Co. Ltd~ - 24% reduction) MSC-V .. (ex Pittsburgh Carbon Co. Ltd. - 21% reducti6n) Actibon X (ex Hooker,.Mexico - 17%. reduction) The other carbons removed less than 15% of the nitric oxide. Obviously, if more carbon is used, higher reductions can be obtained. For example, one gramme of the. HCN-NO carbon will remove 70% of the nitric oxide. BAT Industries document for Province of British Columbia 14 November 2000 BAT I~US~FRIES ........ 00290484

- 2 - Laboratory Prepared Materials The most effective material found so far is sodium chlorite supported on porous alumina at a level of 20%. A filter containing 100mg of this material removed 80% of the nitric oxide. Sodium chlorite has been patented ~y Eastman and may be considered to be an unacceptable additive as chlorine dioxide is released during smoking the cigarette. The next most effective material is.powdered cobalt oxide, C0304, which removes 55% for 50mg of material. Other CO304 catalysts have been prepared, some supported on alumina, and remove 30-40% of nitric oxide (100mg). Many. other materials have been evaluated, but are not considered to be potentially useful. A sample of Alumina-PEI has been requested from Brown & Williamson. This project is being vigorously persued, and other materials will be investigated. Finally, it should be noted that, so far, the potential usefulness of ventilation has not been studied deliberately. However, during the evaluation of competition brands such as Flint and Clint the results indicated that ventilation would be a f~rther means of reducing nitric oxide. Very recently it has been shown that filters wrapped in porous wrappers r~duce the deliveries of nitric oxide. This approach will be.studied further as part of this project. BAT Industries document for Province of British Columbia 14 November 2000 BAT ~USTRIES ....... 00290485