Adsorptive Removal of Rhodamine B with Activated Carbon Obtained from Okra Wastes
Chemical Engineering Communications, cilt.204, sa.7, ss.772-783, 2017 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 204 Sayı: 7
- Basım Tarihi: 2017
- Doi Numarası: 10.1080/00986445.2017.1319361
- Dergi Adı: Chemical Engineering Communications
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.772-783
- Anahtar Kelimeler: Activated carbon, Adsorption, Isotherms, Okra waste, Rhodamine B
- Kırklareli Üniversitesi Adresli: Evet
Özet
This study aimed at preparing and optimizing an activated carbon (OAC) obtained from dry okra wastes by chemical activation with zinc chloride. Also, Rhodamine B removal performance from aqueous solution was analyzed by using this optimized activated carbon. The characterization of the resultant activated carbon, with a high surface area of 1044 m2/g, was carried out using thermogravimetric analysis, Brunauer–Emmett–Teller model, t-plot, N2 adsorption/desorption isotherms, density functional theory, elemental analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and the point of zero charge. Furthermore, the effects of operating conditions (contact time, initial concentration, adsorbent dosage, temperature, and pH) on Rhodamine B adsorption onto OAC were investigated. Langmuir model was determined to be the best adsorption process, and the maximum adsorption capacity was calculated to be 321.50 mg/g at 25°C. Also, the intraparticle diffusion and boundary layer diffusion were involved in RhB adsorption onto OAC. Moreover, OAC adsorption curves of Rhodamine B followed pseudo second-order model. At 25°C, Gibbs free energy, enthalpy, and entropy obtained from thermodynamic studies were determined to be −27.87 kJ/mol, 13.03 kJ/mol, and 0.15 kJ/mol K, respectively. These thermodynamic values revealed that Rhodamine B adsorption onto OAC was feasible, endothermic, physical, and spontaneous.