Preparation and Characterization of Char Carbon Obtained by Carbonization of Unused Cigarette Filter Rods: The Product Application Assessment

The development of carbonaceous materials such as biochar has triggered a hot spot in materials application. In this study, a new type of char carbon was developed from raw cigarette filter rods (CFRs) via a carbonization process under moderate conditions (<i>T</i> = 550 °C; <i>t_res</i> = 1 h) (CFR char carbon). The produced char was characterized by ATR-FTIR (Attenuated total reflectance-Fourier-transform infrared) spectroscopy, XRD (X-ray diffraction) analysis, GC-MS (Gas Chromatography-Mass Spectrometry), FESEM-EDS (Field-Emission Scanning Electron Microscopy-Energy-dispersive X-ray spectroscopy) technique, XPS (X-ray photoelectron spectroscopy), and N₂ adsorption/desorption (BET) measurements. The obtained carbon material is rich in oxygen-containing functional groups (i.e., C=O, C-O, -C(=O)-CH₃, C-O-C, C-OH, and O=C-O, with chemisorbed oxygen), containing significant amounts of calcium (that originates from CaCO₃) and silicon (Si), generated by reduction of SiO₂. It was found that the formation of char(C)/n-alkane composite material makes that CFR char have a high compressive strength improvement. Moderate carbonization has contributed to the creation of such material that has a fairly high specific surface area (320.93 m²/g), exhibiting a complex hierarchical structure that was characterized by composite Type I/IV(a) isotherm, associated with micro-/mesoporous carbon material. In addition, more directional extensions of this research for future work were proposed, including the implementation of electrochemical research.