Uptake of Air Pollutants by Paper
| Main Authors: | , , |
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| Format: | Article |
| Language: | English Slovak |
| ISSN: | ISSN 0034-5806 |
| Online Access: | http://www.viks.sk/chk/res_3_00_117_137.doc |
| Abstract: | Summaries. The objectives of the study have been to investigate the uptake of air pollutants (SO2, NO2 and OJ, especially synergistic effects when these pollutants are present together, and the effects of climate. The initial dry deposition of the pollutants onto a paper surface was studied using on-line gas analysis. The paper samples were exposed to synthetic atmospheres with careful control of pollutant concentrations, relative humidity and flow conditions. The depositions of NO2 and O2 were judged to be insignificant in the present study. The investigated papers showed a low tendency to pick up SO2 alone. The deposition of SO2 was however enhanced by the presence of the other pollutants, and also by a high relative humidity. The addition of NO2 increased the pick-up of SO2 at high relative humidities, while the addition of O3 , also increased the pick-up of SO2 at intermediate humidities. The presence of CaCO3 favoured a high pick-up of SO2 on the alkaline papers. However, it was found that the alkaline papers responded differently to SO2 . This may indicate that the alkali reserve under adverse conditions is either too rapidly consumed or passivated, probably due to the paper manufacturing process and the origin of the filler. Conclusions. The main conclusions from the present study of how air pollutants are deposited on and attack paper materials may be stated as follows: ˙ Investigated papers showed slow deposition rates of SO2 on exposure to SO2 alone. ˙ The addition of NO2 increased the uptake of SO2 at high relative humidities. ˙ The addition of O3 also increased the uptake of SO2 at intermediate humidities. ˙ The capacity of an alkaline buffer for neutralising acid pollutants in paper probably depends upon the paper manufacturing process and the origin of the filler. ˙ The relative humidity in repositories should be kept as low as possible in order to minimise the interaction of air pollutants in paper. |
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| ISSN: | ISSN 0034-5806 |
