ΔΗΜΟΣΙΕΥΣΗ - INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
Title: Chemical looping glycerol reforming for hydrogen production by Ni@ZrO2 nanocomposite oxygen carriers [view paper]
Journal: International Journal of Hydrogen Energy 43 (2018) 13200-13211.
Authors: B. Jiang1,2, L. Li1, Z. Bian2, Z. Li2, Y. Sun1, Z. Sun1, D. Tang1,*, S. Kawi2,**, B. Dou3, M.A. Goula4
1Key Laboratory of Ocean Engineering Utilization and Energy Conservation of Ministry of Education, Dalian University of Technology, Dalian 116023, China
2Department of Chemical & Biomolecular Engineering, National University of Singapore, Singapore 117585, Republic of Singapore
3Scholl of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
4Laboratory of Alternative Fuels and Environmental Catalysis (LAFEC), Department of Environmental and Pollution Control Engineering, Western Macedonia University of Applied Sciences, GR-50100, Greece
Abstract
The research describes the synthesis of nanocomposite Ni@ZrO2 oxygen carriers (OCs) and lanthanide doping effect on maintaining the platelet-structure of the nanocomposite OCs. The prepared OCs were tested in chemical looping reforming of glycerol (CLR) process and sorption enhanced chemical looping reforming of glycerol (SE-CLR) process. A series of characterization techniques including N2 adsorption-desorption, X-ray diffraction (XRD), inductively coupled plasma optical emission spectrometry (ICP-OES), high resolution transmission electron microscopy (HRTEM), H2 temperature-programmed reduction (H2-TPR), H2 pulse chemisorption and O2 temperature-programmed desorption (O2-TPD) were used to investigate the physical properties of the fresh and used OCs. The results show that the platelet-stack structure of nanocomposite OCs could significantly improve the metal support interaction (MSI), thus enhancing the sintering resistance. The effect of lanthanide promotion on maintaining this platelet-stack structure increased with the lanthanide radius, namely, La3+ > Ce3+ > Pr3+ > Yb3+. Additionally, the oxygen mobility was also enhanced because of the coordination of oxygen transfer channel size by doping small radius lanthanide ions. The CeNi@ZrO<sub< a="">>2 showed a moderate ‘dead time’ of 220 s, a high H2 selectivity of 94% and a nearly complete glycerol conversion throughout a 50-cycle CLR test. In a 50-cycle SE-CLR stability test, the CeNi@ZrO2-CaO showed high H2 purity of 96.3%, and an average CaCO3 decomposition percentage of 53% without external heating was achieved.