Khataee, AlirezaKayan, BerkantKalderis, DimitriosKarimi, AtefehAkay, SemaKonsolakis, Michalis13.07.20192019-07-2913.07.20192019-07-2920171350-41771873-2828https://doi.org/10.1016/j.ultsonch.2016.09.004https://hdl.handle.net/20.500.12451/5692The Fe3O4-loaded coffee waste hydrochar (Fe3O4-CHC) was synthesized using a simple precipitation method. The as-prepared adsorbent was characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and Fourier transform infrared spectroscopy (FT-IR). The EDX analysis indicated the presence of Fe in the structure of Fe3O4-CHC. The specific surface area of hydrochar increased from 17.2 to 34.7 m(2)/g after loading of Fe3O4 nanoparticles onto it. The prepared Fe3O4-CHC was used for removal of Acid Red 17 (AR17) through ultrasound-assisted process. The decolorization efficiency decreased from 100 to 74% with the increase in initial dye concentration and from 100 to 91 and 85% in the presence of NaCl and Na2SO4, respectively. The synthesized Fe3O4-CHC exhibited good stability in the repeated adsorption-desorption cycles. The high correlation coefficient (R-2 = 0.997) obtained from Langmuir model indicated that physical and monolayer adsorption of dye molecules occurred on the Fe3O4-CHC surface. Furthermore, the by-products generated through the degradation of AR17 was identified by gas chromatography mass spectrometry analysis.eninfo:eu-repo/semantics/closedAccessFe3O4 NanoparticlesHydrocharMagnetiteUltrasoundSonolysisDye removalArticle35728010.1016/j.ultsonch.2016.09.00427637143Q1WOS:000390494300007N/A