In this work, preparation, characterization and nitrate removal ability of a chemically modified cellulose nanocrystal (CPTMS/CNC) were investigated for the first time. The FTIR, FESEM, EDX, and TG analyses confirmed the successful modification of the cellulose nanocrystal (CNC) by 3-chloro propyl trimethoxysilane (CPTMS) and the thermal stability of CPTMS/CNC. The optimum removal efficiency (86.5%) occurred at initial pH of 7 and room temperature (~25 °C) with an initial nitrate concentration of 20 mg L-1, contact time of 10 min, and CPTMS/CNC dosage of 3 g L-1. The nitrate adsorption dropped noticeably in the presence of sulfate, followed by bicarbonate, chloride and phosphate, respectively. The kinetic adsorption data were fitted well with the pseudo-second-order kinetic model and the adsorption process involved two stages. The equilibrium adsorption data obeyed the Freundlich isotherm model. Thermodynamic analysis suggested a spontaneous and exothermic adsorption process with a decrease in random collisions at the solid-solution interface.
