Adsorption and Diffusion Properties of Tobacco Composition and Additive: A Multiscale Theoretical Study

Abstract

Abstract Unveiling the influence effects of H2O and others (propylene glycol, glycerol and nicotine) on adsorption and diffusion in tobacco is of great importance in cigarette industry while being a challenge issue under three different factors (temperature, concentration and aperture size). Herein, via first-principles density functional theory ( DFT ) simulations, it is found that H2O tends to be adsorbed on O-top sites rather than H-top sites due to the stronger H-bond attraction, on which existed H2O is also easy to desorb because of the weak physical adsorption. Moreover, via molecular dynamics ( MC ) calculations, under 300 K − 500 K range, the diffusion of H2O and other components increases as increasing temperature due to the intensified thermal exercise. Regarding effect of concentration (4% − 14%), with upgrading the concentration, the diffusion property elevates and then decreases for H2O and others, which may be related to the stability of the system caused by H-bonds and the free accommodation space of cellulose structure. Focused on influence of aperture size, as the pore size increases, the diffusion of H2O and others increases significantly due to the expansion of the free space and the diffusivity of H2O is higher than that of others on account of smaller structural form.