BACKGROUND: This study investigates the adsorption of methylene blue (MB) and malachite green (MG) onto a novel biosorbent. Rapid industrialization pollutes water resources, causing serious environmental problems. Physical and chemical treatments were performed for biosorbent modification.RESULTS: In the present work, nano (n)TiO 2 was inserted into chitosan (Cts)-epichlorohydrin (ECH)-plum kernel shell (PKS) and the final product was characterized by various modern techniques such as Fourier transform infrared, X-ray diffraction, scanning and transmission electron microscopy and thermogravimetric analysis. Under optimized conditions, the maximum adsorption capacities of MB and MG by Cht/PKS/nTiO 2 -ECH (termed nTiO 2 -Composite) determined by the Langmuir model were 86.96 and 108.70 mg g −1 , respectively. Thermodynamic parameters such as ΔG°, ΔH°, ΔS°and E a were calculated, confirming the interaction of dyes with nTiO 2 -Composite as exothermic and spontaneous.CONCLUSIONS: This study shows that the newly synthesized nTiO 2 -Composite has a very high performance in dye removal.