Biomass carbonaceous aerogels (BCA) have shown wide applications for environment and energy. Herein, we present a facile method toward Th(octyl-decyl) amine-modified BCA (BCA@N235) by using a hydrothermal synthesis and impregnating process. The synthesized BCA@N235 exhibits an excellent adsorption performance for I- ions, and the adsorption equilibrium requires only 2 h, which is faster than most of materials reported previously. In addition, the adsorption process is more consistent with the classic Langmuir and pseudo second-order models. The maximal adsorption capacity for I- ions is 0.85 mmol/g at the initial pH of 2.0. The adsorption mechanism is further explored by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy analysis, and corresponding control experiments, and it is proposed that the fast removal of I- ions by BCA@N235 is ascribed to the protonation-induced electrostatic interaction between I- ions and aerogel materials, in addition, a large number of macroporous structure on the surface and internal of BCA@N235 are beneficial to adsorb iodine ions. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.