The microstructure and stability of a Ni-nano-CaO/Al2O3 reforming catalyst under carbonation–calcination cycling conditions. (4th May 2015)

• Record Type: Journal Article
• Authors: Xue, Xiaochong; Wu, Sufang
• Is Part Of: International journal of hydrogen energy. Volume 40:Number 16(2015)
• Page Start: 5617
• Page End: 5623
• Publication Date: 2015-05-04
• Subjects: Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2015.02.032
• Languages: English
• ISSNs: 0360-3199

Abstract

<abstract xml:lang="en" abstract-type="author" id="abs0010"> <title id="sectitle0010">Abstract</title> <sec> <p id="abspara0010">The paper investigated the effect of carbonation–calcination cycling conditions on the microstructure and CO<sub>2</sub> sorption property of a sorption complex catalyst. The carbonation operation condition consisted of temperature of 600 °C with 20% CO<sub>2</sub>–80% N<sub>2</sub> and 20% CO<sub>2</sub>–80% steam atmosphere to simulate the methane reforming reaction conditions; the calcination condition was 800 °C with 100% N<sub>2</sub>. The Brunauer–Emmer–Teller (BET) surface area and thermogravimetric analysis (TGA) were measured to investigate the microstructure and variation in sorption property of the catalyst after multiple cycles under each condition. Results showed that the microstructure and CO<sub>2</sub> sorption capacity of the sorption complex catalyst decayed significantly in the initial carbonation–calcination cycles, especially under a steam atmosphere. X-ray diffraction analysis revealed that a stable compound Ca<sub>12</sub>Al<sub>14</sub>O<sub>33</sub> formed gradually during the initial carbonation–calcination cycle seven at a temperature of 800 °C. A model is proposed to explain the observed effect of carbonation–calcination cycling on Ca<sub>12</sub>Al<sub>14</sub>O<sub>33</sub> formation. Furthermore, based on our findings, a new sorption complex catalyst was prepared by pretreating at a high temperature of 900 °C. Evaluation of the catalyst prepared by the ReSER hydrogen production process through 10 circulations revealed significant improvement instability.</p> </sec> </abstract>