Atmospheric Environment 40 (2006) 2929–2934 QSPR prediction of the Dubinin–Radushkevich’s k parameter for the adsorption of organic vapors on BPL carbon Pablo R. Duchowicz à , Heriberto Castan˜eta, Eduardo A. Castro, Francisco M. Ferna´ndez, Jose´ Luis Vicente INIFTA, Divisio´n Quı´mica Teo´rica, Departamento de Quı´mica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Diag. 113 y 64, Suc. 4, C.C. 16, (1900) La Plata, Argentina Received 14 September 2005; received in revised form 3 January 2006; accepted 3 January 2006 Abstract We propose a QSPR treatment to model a diverse set of pure organic vapors including 36 k parameters from the Dubinin–Radushkevich adsorption isotherm equation. From 814 molecular descriptors provided by the Dragon 5 software and the Replacement Method, we obtain an appropriate four-variables model with R ¼ 0.9334 and R l–10%–o ¼ 0.8047. By means of this relationship, we predict 33 unknown values of k for structurally related vapors, enabling now to build their isotherms on BPL adsorbent at any desired temperature. r 2006 Elsevier Ltd. All rights reserved. Keywords: QSPR theory; Physical adsorption; Isotherm; Carbon adsorbent; Modeling 1. Introduction During the last decades, the adsorption of vapors on microporous carbons has become an appropriate industrial-scale technology for the control of air emissions of organic vapors because of its known advantages with respect to other methodologies: possibility of pure product recovery for reuse, high removal efficiency at low inlet concentrations, and low fuel/energy costs. Usually, one faces experimental difficulties in measuring adsorption capacities for different combinations of adsorba- te–adsorbent systems, such as, for example, that the time required to reach equilibrium at a given gas- phase concentration could exceed 400 h to yield just one data point on the isotherm (Rasmuson, 1984). Such difficulties motivated researchers to develop predictive methods to model the adsorption capa- cities and isotherms. The popular and simple Dubinin–Radushkevich isotherm equation (D–R), deduced from the Poten- tial Theory of Physical Adsorption proposed by Polanyi (1914), has proved to be an adequate predictive tool (Noll et al., 1992; Reucroft et al., 1971; Urano et al., 1982). Its linear form reads ln W ¼ ln W 0  k R gas T ln p sat p     2 , k ¼ 1 bE 0   2 , ð1Þ ARTICLE IN PRESS www.elsevier.com/locate/atmosenv 1352-2310/$ - see front matter r 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.atmosenv.2006.01.022 à Corresponding author. Tel.: +54 221 425 7430; fax: +54 221 425 4642. E-mail address: pabloducho@yahoo.com.ar (P.R. Duchowicz).