Carbon dioxide adsorbents from flame-made diesel soot nanoparticles.
Gerardo D J Guerrero Peña, K Suresh Kumar Reddy, Anish Mathai Varghese, Azhagapillai Prabhu, Aasif A Dabbawala, Kyriaki Polychronopoulou, Mark A Baker, Dalaver Anjum, Gobind Das, Cyril Aubry, Mohamed I Hassan Ali, Georgios N Karanikolos, Abhijeet Raj, Mirella Elkadi
Author Information
Gerardo D J Guerrero Peña: Department of Chemistry, Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates. Electronic address: gerardo.pena@ku.ac.ae.
K Suresh Kumar Reddy: Department of Chemical Engineering, Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates; Center for Catalysis and Separation (CeCaS), Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates.
Anish Mathai Varghese: Department of Chemical Engineering, Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates; Center for Catalysis and Separation (CeCaS), Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates.
Azhagapillai Prabhu: Department of Chemistry, Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates.
Aasif A Dabbawala: Department of Mechanical Engineering, Khalifa University, P.O. Box 127788, Abu Dhabi 127788, United Arab Emirates.
Kyriaki Polychronopoulou: Center for Catalysis and Separation (CeCaS), Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates; Department of Mechanical Engineering, Khalifa University, P.O. Box 127788, Abu Dhabi 127788, United Arab Emirates.
Mark A Baker: The Surface Analysis Laboratory, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 4DL, UK.
Dalaver Anjum: Center for Catalysis and Separation (CeCaS), Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates; Department of Physics, Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates.
Gobind Das: Department of Physics, Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates.
Cyril Aubry: Electron Microscopy Core Labs, Khalifa University, P.O. Box 127788, Abu Dhabi 127788, United Arab Emirates.
Mohamed I Hassan Ali: Department of Mechanical Engineering, Khalifa University, P.O. Box 127788, Abu Dhabi 127788, United Arab Emirates.
Georgios N Karanikolos: Department of Chemical Engineering, Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates; Center for Catalysis and Separation (CeCaS), Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates; Research and Innovation Center on CO(2) and H(2) (RICH), Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates; Department of Chemical Engineering, University of Patras, 26500 Patras, Greece.
Abhijeet Raj: Department of Chemical Engineering, Indian Institute of Technology Delhi, Hauz Khas, Delhi, India.
Mirella Elkadi: Department of Chemistry, Khalifa University, P.O. Box 127788, Abu Dhabi, United Arab Emirates. Electronic address: mirella.elkadi@ku.ac.ae.
Carbon dioxide (CO) is the top contributor to global warming. On the other, soot particles formed during fuel combustion and released into the atmosphere are harmful and also contribute to global warming. It would therefore be highly advantageous to capture soot and make use of it as a feedstock to synthesize carbon-based materials for applications such as carbon dioxide adsorption. In this work, flame-made diesel soot nanoparticles were used to produce a variety of activated carbons by combined oxidative treatment with hydrogen peroxide (HO) and potassium hydroxide (KOH), and their performance towards CO adsorption was evaluated. The effect of the chemical activation of soot with HO for different reaction times and with KOH on the physicochemical properties of the activated carbons was investigated and compared to fresh soot. Interestingly, hollow aggregates of carbonaceous nanoparticles of a high interplanar distance, reduced polycyclic aromatic hydrocarbons (PAH) size, shorter PAH stacks, mesoporous structure, and a high content of oxygen functionalities along with other structural defects in PAHs were obtained in the synthesized activated carbons. Among the various analysis techniques employed, Raman spectroscopy indicated that the I/I ratio in soot decreased after simultaneous chemical treatment, though it did not indicate any enhancement in the graphitic character since the carbonyl and carboxylic containing PAHs and monovacancies (which cause defects in PAHs) also contribute to the increase in the intensity of the graphitic band. The activated carbons possessed promising CO adsorption capacities, adsorption kinetics and CO/N selectivity. For example, one of the activated carbons, following HO treatment for 9 h and a subsequent KOH activation, exhibited a CO adsorption capacity of 1.78 mmol/g at 1 bar and 25 °C, representing an increase of 161 % in capacity as compared to fresh soot. Hollow aggregates of carbonaceous nanoparticles consisting of shorter PAHs with a larger number of defects led to enhanced CO adsorption rate and CO/N selectivity on activated carbons.
