Kazak, OmerEker, Yasin RamazanAkin, IlkerBingol, HalukTor, Ali2024-02-232024-02-2320170944-13441614-7499https://doi.org/10.1007/s11356-017-9937-xhttps://hdl.handle.net/20.500.12452/11231This study reports the eco-friendly preparation of a novel composite material consisting of red mud and carbon spheres, denoted as red mud@C composite, and its application for the removal of 2,4-dichlorophenoxyacetic acid herbicide (2,4-D) from aqueous solution. The preparation route has a green approach because it follows the low-energy consuming one-step hydrothermal process by using starch as a renewable carbon precursor and red mud as a waste from aluminum production industry. Characterization of the red mud@C composite was performed by FT-IR, TGA, SEM, TEM, BET, XRD, and Raman microscopy analyses. The batch adsorption studies revealed that the red mud@C composite has higher 2,4-D adsorption efficiency than those of the red mud and the naked carbon spheres. The maximum removal at initial pH of 3.0 is explained by considering the pKa of 2,4-D and pH of point of zero charge (pH(pzc)) of the composite material. The adsorption equilibrium time was 60 min, which followed the pseudo-second-order kinetic model together with intra-particle diffusion model. The isotherm analysis indicated that Freundlich isotherm model better represented the adsorption data, with isotherm parameters of k [15.849 (mg/g) (mg/L)(-1/n) ] and n (2.985). The prepared composite is reusable at least 5 cycles of adsorption-desorption with no significant decrease in the adsorption capacity.eninfo:eu-repo/semantics/closedAccessRed MudCarbon SpheresHydrothermal ProcessComposite AdsorbentHerbicide AdsorptionArticle24292305723068288251752-s2.0-85027696306Q1WOS:000412453500026Q210.1007/s11356-017-9937-x