Predictions of Gibbs Free Energies for the Adsorption of Polyaromatic and Nitroaromatic Environmental Contaminants on Carbonaceous Materials: Efficient Computational Approach

摘要

The adsorption of benzene, polycyclic aromaticnhydrocarbons (PAHs), and nitroaromatic compounds (NACs)non the carbonaceous surfaces from the gas phase and waternsolution was investigated. Several different levels of theorynwere applied, including DFT-, MP2-, and CCSD(T)-basednmethods, to find an approach that is computationallyninexpensive and can provide accurate thermodynamicnparameters for studied adsorption phenomena. The methodsnand techniques used (including cluster and periodicnapproximations) were evaluated on the basis of comparisonnwith available experimental data. The optimized structures ofncalculated complexes are obtained, and the interaction energiesnand Gibbs free energies are predicted. Good agreement wasnrevealed for the theoretical and experimental adsorption energies of benzene and PAHs adsorbed on the carbon surfaces. Thenadsorption of benzene, PAHs, and NACs on carbon is suggested to be effective from the gas phase for all studied compounds andnfor PAHs and NACs also from water solution at room temperature.