A study on CO and CO2 methanation over Co/CeO2 and Co/ZrO2 catalysts
- 주제(키워드) Co–based catalyst , CO methantion , CO2 methanation
- 발행기관 아주대학교
- 지도교수 Eun Duck Park
- 발행년도 2021
- 학위수여년월 2021. 2
- 학위명 석사
- 학과 및 전공 일반대학원 에너지시스템학과
- 실제URI http://www.dcollection.net/handler/ajou/000000030803
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
The high increase of atmospheric CO2 concentration has been received a great deal of public attention in recent decades. In order to reduce the atmospheric carbon footprint, several feasible promising processes have been developing. One of them is the CO2 utilization concept in which CO2 is likely to play a role as the initial carbon source. The power-to-gas (P2G) in which CO2 is converted into methane through methanation is the representative concept. Cobalt metal has been known as the most active component not only for Fischer – Tropsch reaction but also for methanation. Therefore, cobalt was chosen as an active component and the two preparation methods such as co–precipitation and wet impregnation were compared in this study to develop the active cobalt–based catalysts for both CO and CO2 methanation. Furthermore, the effect of the pretreatment conditions especially calcination temperature on the catalytic activity was also examined. In the case of Co-CeO2 catalyst prepared with a co-precipitation method, the catalyst calcined at 500 ℃ showed the better catalytic performance than those calcined at 300 or 700 ℃. In the case of Co-ZrO2 catalyst prepared with a co-precipitation method, the catalyst calcined at 700 ℃ exhibited the better catalytic activity than those calcined at 500 or 800 ℃. Among the tested supports such as CeO2, ZrO2 and SiO2, ceria was proven as the best support. The co-precipitated method appears to be better than the wet impregnation one for ceria- and zirconia-supported cobalt catalysts. The catalytic activity appears to be closely related to the catalytically active surface area (CASA), surface basicity of the support and interaction between the cobalt metal and the support.
more목차
CHAPTER 1 INTRODUCTION 1
1.1 Objective 1
1.2 Methanation catalysts 4
1.2.1 Active components 4
1.2.2 Supports 6
1.2.3 Promoters 8
1.3 Preparation methods 9
1.4 Reaction mechanism 12
1.4.1 CO2 methanation mechanism 12
1.4.2 CO methanation mechanism 12
1.5 Catalyst deactivation 15
1.5.1 Poisoning 15
1.5.2 Fouling 15
1.5.3 Sintering 16
CHAPTER 2 EXPERIMENTAL 21
2.1 Catalysts preparation 21
2.1.1 Co0.1M0.9Ox catalysts preparation 21
2.1.2 Co0.9M0.1Ox catalysts preparation 21
2.1.3 Co/MO2 (M = Ce, Si, Zr) catalysts preparation 21
2.2 Catalyst characterization 22
2.3 Catalyst performance evaluation 24
CHAPTER 3 RESULTS AND DISCUSSION 26
3.1 Cobalt – based catalysts by co – precipitation method 26
3.1.1 Characterization 26
3.1.2 CO methanation 34
3.1.3 CO2 methantion 39
3.2 Cobalt – based catalysts prepared by wet impregnation (WI) method 44
3.2.1 Characterization 44
3.2.2 CO methanation 52
3.2.3 CO2 methanation 56
CHAPTER 4 CONCLUSION 59
REFERENCES 60
