Vol.:(0123456789) 1 3 Carbon Letters https://doi.org/10.1007/s42823-020-00187-1 ORIGINAL ARTICLE DFT and experimental study on adsorption of dyes on activated carbon prepared from apple leaves Mohamed Helmy Abdel‑Aziz 1,2  · Elsayed Zakaria El‑Ashtoukhy 2  · Mohamed Bassyouni 3,4  · Ahmed Farouk Al‑Hossainy 5,6  · Eman M. Fawzy 7,8  · Shereen M. S. Abdel‑Hamid 9  · Mohamed Shafck Zoromba 1,10 Received: 30 March 2020 / Revised: 25 July 2020 / Accepted: 7 September 2020 © Korean Carbon Society 2020 Abstract This work reports utilization of apple leaves as a source of activated carbon. Activated carbon from apple leaves is prepared by two diferent methods, thermal activation where AC1 is obtained and chemical activation using H 3 PO 4 and ZnCl 2 where AC2 and AC3 are obtained, respectively. XRD analysis revealed that all types of prepared ACs have a semi-crystalline nature with a mean crystallite size of 13, 21.02, and 39.47 nm for AC1, AC2, and AC3, respectively. To identify the most suitable desorption temperature, the exothermic behavior was discovered for the three types of ACs by DSC. The exothermic onset temperatures are 340 °C, 200 °C, 400 °C, or AC1, AC2, and AC3, respectively. The point of zero charge for the three types of ACs is 8.6, 7.3, and 2.5 for AC1, AC2, and AC3, respectively. The BET surface area analysis data demonstrated that mesoporous structure was developed in AC1 and AC2, while a microporous structure was developed in AC3. Quantum chemical calculations for ACs is carried out using Density Functional Theory (DFT). Application of the prepared ACs in adsorption of basic dye C.I. base blue 47 is studied. The maximum removal efciency was 65.1%, 96% and 99% for AC1, AC2, and AC3, respectively under the infuence of diferent operating aspects. Adsorption data are modeled by Langmuir, Freundlich, and Temkin isotherms. The data revealed that adsorption of basic dye C.I. base blue 47 on AC1 follows Langmuir isotherm and adsorption on AC2 and AC3 follows Freundlich isotherm. Keywords Activated carbon · Apple leaves · Adsorption · BET · DFT · Basic dye List of symbols A T Temkin isotherm equilibrium binding constant, L g −1 B T Constant related to heat of sorption, J mol −1 b T Temkin isotherm constant C o Initial concentrations of the dye in solution, mg L −1 C e Final concentrations of the dye in solution, mg L −1 D Crystal size Online ISSN 2233-4998 Print ISSN 1976-4251 * Mohamed Helmy Abdel-Aziz mhmossa@kau.edu.sa; mhmousa@alexu.edu.eg; helmy2002@gmail.com 1 Chemical and Materials Engineering Department, King Abdulaziz University, Rabigh 21911, Saudi Arabia 2 Chemical Engineering Department, Faculty of Engineering, Alexandria University, Alexandria, Egypt 3 Department of Chemical Engineering, Faculty of Engineering, Port Said University, Port Fouad, Egypt 4 Materials Science Program, Zewail City of Science and Technology, University of Science and Technology, October Gardens, 6th of October, Giza 12578, Egypt 5 Chemistry Department, Faculty of Science, New Valley University, 72511 Al-Wadi Al-Gadid, Al-Kharga, Egypt 6 Chemistry Department, Faculty of Science, Northern Border University, Arar 1321, Saudi Arabia 7 Faculty of Science and Arts at Al-Rass, Al-Rass 51921, Qassim University, Qassim, Saudi Arabia 8 Chemistry Department, Faculty of Science, Aswan University, Aswan, Egypt 9 Department of Chemical Engineering, The Egyptian Academy for Engineering and Advanced Technology, Ministry of Military Production, Cairo, Egypt 10 Chemistry Department, Faculty of Science, Port Said University, Port-Said 42521, Egypt