| Abstract
| - Considering that phenanthrene (Phe) is one of the main pollutants in the waste flue gasesfrom organic material combustion, the aim of this paper is to examine the use of carbon materialsto remove low concentrations of Phe from a hot exhaust gas stream as a function of its moisturecontent. Adsorption isotherms were measured with steam and Phe concentrations in the rangesof 0−20% and 0.02−3.2 ppmv, respectively. Three classic models [Langmuir, Freundlich, andDubinin−Radushkevich (DR)] were applied and their parameters were then determined byregression analysis. It was found that all isotherms fitted the DR model. The determinedparameters showed that, for a carbonaceous material, the higher the steam percentage (in volume)in the gas stream, the lower its Phe adsorption capacity. Results also showed that within theexperimental conditions the Phe adsorption capacities of the carbonaceous materials in humidgas streams could be related to Phe concentration by the Langmuir model. The Freundlich modelproved to be the most successful in describing the Phe adsorption behavior in dry gas streams.The effect of adsorbent characteristics on Phe adsorption from humid gas streams was determinedfrom correlation coefficients between the adsorption capacities of sixteen carbonaceous materialsand their textural parameters. The total micropore volume (pore size diameter < 2 nm) was theparameter that controlled the Phe adsorption both in humid and dry gas streams. Moreover, thedifference, in percentage between adsorption capacities in dry and humid gas streams (10% steampercentage) was positively correlated with the narrow micropore volume (pore size diameter <0.7 nm) with a statistical significance level higher than 99%.
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