(6bw) One-Step Synthesis of Oxide Catalysts Using Aerosol Reactors for Environmental Applications: Theoretical and Experimental Study

Research Interests: I am interested in the active phases of catalysts and catalytic performance on those active phases. During my PhD, I have been working on catalytic O₂ removal from oxy-coal combustion system by using metal oxide catalysts and noble metal doped metal oxide catalysts. Here is the detail of my PhD research:

CO₂ emission from fossil fuel combustion systems is one of the major contributors to global warming. Oxy-coal combustion has been developed as a promising technique to effectively capture CO₂ in power plants. Because pure O₂ is used to combust coal, a concentrated CO₂ stream (~63%) can be achieved in an exhaust. The concentrated CO₂ stream can be further utilized for enhanced oil recovery (EOR), however, the O₂ level in the stream (~ 3%) should be reduced to satisfy the requirement for EOR (~ 100 ppmv) [1]. To resolve this problem, catalytic O₂ removal with CH₄ has been recently applied with noble metal doped metal oxide catalysts and high O₂ conversions were reported [2, 3]. Although high O₂ conversions were obtained, there is still debate on the active phase of metal oxide catalysts and kinetics during O₂ removal reaction. For enhancing the catalytic performance, a fundamental understanding of the active phase of catalysts and kinetics during O₂ removal reaction is required.

Metal oxide catalysts and noble metal doped metal oxide catalysts are synthesized using aerosol reactors in which a continuous one-step process can be applied and so additional processes such as drying and calcination are not necessary. Active phases of the synthesized catalysts are investigated based on both analytical (catalytic properties) and experimental results (kinetic characteristics). A correlation between the active phase of catalyst and reaction rate constant is obtained. The catalytic properties are optimized by combining theoretical study and experiments. An autocatalytic effect of CO₂ (balance and product) on O₂ removal is also found, which is supported by density functional theory calculations and experimental results. These findings help me to fully understand both active sites of catalysts and kinetics during O₂ removal.

References:

[1] DOE/NETL, Quality guidelines for energy system studies: CO₂ impurity design parameters, (2013).

[2] Q. Zheng, S. Zhou, M. Lail, K. Amato, Oxygen removal from oxy-combustion flue gas for CO₂ purification via catalytic methane oxidation, Ind Eng Chem Res, 57 (2018) 1954-1960.

[3] A. N. Kuhn, Z. Chen, Y. Lu, H. Yang, Sequential oxygen reduction and adsorption for carbon dioxide purification for flue gas applications, Energy Technol-Ger, (2018).

Teaching Interests: I am interested in courses related with chemical kinetics and catalysis.