Carbon nanotubes as adsorbents for uranyl ions from aqueous solutions: A molecular dynamics study

Functionalized carbon nanotubes are probed as adsorbents for uranyls in aqueous solutions. Protonated (-COOH) and deprotonated (-COO −) carboxyl groups and the factor of their geometrical placement are studied. The nanotube adsorption efficiency is estimated in terms of corresponding radial distribution functions and fractions of uranyls bound to adsorbate. The simulations show that the charged -COO − groups readily associate with uranyls, contrary to the -COOH case. The results also indicate that the split distribution of the functional groups is more efficient, rather than a dense placement, when the groups form a common attractive domain.