The application of ostrich bone waste-loaded a cationic surfactant (OBW-OH-CTABr) bioadsorbent for benzene, toluene, ethylbenzene and p-xylene (BTEX) removal from the synthetic and real waters have been studied, and the prepared biomaterials were studied by Fourier transform infrared (FTIR), X-ray diffraction (XRD), surface area measurements (BET), scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX) and point of zero (pH(PZC)). The immobilization of CTABr molecules on the framework of modified OBW showed good tendency to adsorb BTEX from aqueous solution. The exposure time to obtain equilibrium for maximum removal of BTEX was observed to be 60 min. The removal kinetics of BTEX has been evaluated in terms of pseudo-first- and-second-order kinetics, and the Freundlich and Langmuir isotherm models have also been utilized to the equilibrium removal data. The removal process was spontaneous and endothermic in nature and followed pseudo-second-order kinetic model. The immobilized CTABr showed high reusability because of its high adsorption efficiency after 12th cycles. The proposed low-cost bioadsorbent could also be utilized to adsorb BTEX from the real water (Anzali lagoon water). The OBW-OH-CTABr composite is indeed an attractive biomaterial for drinking water-based pollutants and act as an adsorbent for BTEX and oil spills especially in third world due to its low-cost preparation and regeneration and clean processing of the biomaterial with no byproducts after utilize. (C) 2015 Elsevier Inc. All rights reserved.