Adsorptive Elimination of Methyl Orange Dye over the Activated Carbon Derived from Bitter Almond Shells. An Isothermal, Thermodynamic, and Kinetic Study

Authors : Rana H. AL-HYALİ, Wael ALKAZZAZ, Duaa H. ALTAMER

Pages : 339-358

Doi:10.18596/jotcsa.1177543

View : 60 | Download : 103

Publication Date : 2023-05-31

Article Type : Research Paper

Abstract :Abstract: Bitter almond shells insert ignore into journalissuearticles values(BAS); were inspected as a low-cost precursor in producing activated carbon insert ignore into journalissuearticles values(AC); through the optimized ZnCl2 activation route. The raw BAS were impregnated with ZnCl2 at multiple ratios insert ignore into journalissuearticles values(1:1 - 3:1 ZnCl2:BAS);, followed by carbonization at various temperatures insert ignore into journalissuearticles values(400 – 800 °C); for different durations insert ignore into journalissuearticles values(30 – 120 minutes); in a tubular reactor. The typical AC sample was prepared using a 1:1 ZnCl2:BAS impregnation ratio and activated at 500 °C for 60 minutes. The AC yield under those conditions was 23.46%. The BET surface area insert ignore into journalissuearticles values(SABET);, Boehm titration method, point of zero charge insert ignore into journalissuearticles values(pHPZC);, Field Emission-Scanning Electron Microscopy insert ignore into journalissuearticles values(FE-SEM);, X-ray diffraction insert ignore into journalissuearticles values(XRD);, Fourier Transform Infra-Red spectroscopy insert ignore into journalissuearticles values(FTIR);, and Energy Dispersive X-ray insert ignore into journalissuearticles values(EDX); of the optimal AC sample were determined. The identification outcomes disclosed that this AC sample is mesoporous with SABET, iodine number, total pore volume, and average pore width of 1221.60 m2/g, 1444.23 mg/g,1.50 cm3/g, and 4.98 nm, respectively. The adsorptive removal of methyl orange insert ignore into journalissuearticles values(MO); dye from its aqueous phase by this AC was accomplished at various solution pH insert ignore into journalissuearticles values(2–10);, different amounts of the AC insert ignore into journalissuearticles values(0.05-0.4 g);, multiple initial concentrations insert ignore into journalissuearticles values(50–400 mg/L);, variable temperature insert ignore into journalissuearticles values(10-50 °C); and varied contact time insert ignore into journalissuearticles values(0–420 min); in a batch- mode operation. The maximum monolayer adsorption capacity of 224.71 mg/g was obtained at 323 K, pH= 2.0, initial insert ignore into journalissuearticles values(MO); concentration of 400 mg/L, 0.25 g AC dose, and 420 minutes contact time. The kinetic outcomes best fitted to the pseudo-2nd -order kinetics model, while the MO equilibrium capacity obeyed the Langmuir model rather than other models. Thermodynamic studies of the MO adsorption by the BAS-derived AC disclosed that the adsorption was spontaneous and endothermic. The adsorption mechanism of MO by the declared AC mostly involved electrostatic attractions and hydrogen bonding interaction. This work demonstrates that BAS is an advantageous raw material for producing low-cost and effectual mesoporous AC carbon with substantive surface area.
Keywords : Activated carbon, Bitter almond shells, Methyl Orange Dye