Illites,　modified　with　cetyltrimethyl　ammonium　bromide　(CTMAB),　were　used　as　adsorbents　for　characterization　by　infrared　spectroscopy　(FTIR),　a　scanning　electron　microscope　(SEM),　X-ray　diffraction　(XRD),　and　thermogravimetric　analysis　(TG).　The　adsorption　properties　of　reactive　brilliant　blue　K-GR　were　investigated,　and　showed　that　the　optimal　adsorption　condition　was　with　a　pH　of　3,　0.3　g　dosage　of　adsorbents,　and　a　0.125　mass　ratio　of　CTMAB　to　illites.　The　adsorption　process　conformed　to　a　pseudo-second-order　reaction　kinetics　equation,　and　the　equilibrium　isotherm　was　well　described　by　the　Langmuir　adsorption　model.　In　thermodynamic　studies,　the　parameters　of　ΔG0<0,　ΔH0>0,　and　ΔS0>0　indicated　that　the　adsorption　process　was　spontaneous　and　endothermic　with　an　increase　in　entropy.　©　2016,　Science　Press.　All　right　reserved.