Modification of biomass-derived activated carbon with magnetic $\alpha $-Fe$_{2}$O$_{3}$ nanoparticles for CO$_{2}$ and CH$_{4}$ adsorption

Authors : Çisem KIRBIYIK

Pages : 687-704

View : 15 | Download : 11

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :Magnetic and nonmagnetic activated carbons insert ignore into journalissuearticles values(ACs); were successfully prepared by using AC obtained from spent coffee grounds insert ignore into journalissuearticles values(SCGs); for use in CO$_{2}$ and CH$_{4}$ capture. SCGs were activated by chemical activation to produce ACs and a magnetic $\alpha $-Fe$_{2}$O$_{3}$/AC composite was prepared by coprecipitation method from the ACs produced. Magnetic and nonmagnetic samples were characterized by X-ray diffraction insert ignore into journalissuearticles values(XRD);, Fourier transform infrared spectroscopy insert ignore into journalissuearticles values(FT-IR);, scanning electron microscopy insert ignore into journalissuearticles values(SEM);, and energy dispersive X-ray spectrometry insert ignore into journalissuearticles values(EDX); techniques. The textural properties of samples were determined by nitrogen adsorption-desorption using the Brunauer--Emmett--Teller insert ignore into journalissuearticles values(BET); and Barrett--Joyner--Halenda insert ignore into journalissuearticles values(BJH); methods. The results showed that the porosity of AC was not blocked by $\alpha $-Fe$_{2}$O$_{3}$ particles. According to adsorption-desorption experiments, the best results were obtained with the magnetic $\alpha $-Fe$_{2}$O$_{3}$/AC sample insert ignore into journalissuearticles values(1.68 mmol g$^{-1}$ for CO$_{2}$ and 0.65 mmol g$^{-1}$ for CH$_{4});$ at 0 \textdegree C and 120 kPa. Adsorption performances were evaluated using four isotherm models. The isosteric heats of adsorption calculated for both adsorbents were smaller than 80 kJ/mol and it revealed that CO$_{2}$ and CH$_{4}$ adsorption is dominated by the physical adsorption. The $\alpha $-Fe$_{2}$O$_{3}$/AC multicycle CO$_{2}$ adsorption tests showed that it can be successfully regenerated with high sorption capacity. The $\alpha $-Fe$_{2}$O$_{3}$/AC composite is a promising adsorbent for potential application.
Keywords : Magnetic composite, activated carbon, CO 2 adsorption, CH 4 adsorption