catalyst
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Let’s talk about why CO2 levels cannot be too high when the catalyst is reduced again :)
I heard that CO2 seems to cause redox reactions that result in the formation of copper carbonate or something similar, which affects activity. This requirement exists in all cases; I just heard about it once during a lecture given by a catalyst manufacturer before starting the vehicle 4 years ago. I haven’t heard any information on it.
I heard that CO2 seems to cause redox reactions that result in the formation of copper carbonate or something similar, which affects activity. This requirement exists in all cases; I just heard about it once during a lecture given by a catalyst manufacturer before starting the vehicle 4 years ago. I haven’t heard any information on it.
Reply to 3# lizhaoye: During reduction, it is generally required that the CO2 partial pressure above the catalyst not exceed 0.12 MP (absolute pressure), meaning that the volume fraction of CO2 must not be more than 20%, in a reduction system with a pressure of 0.5 MP (gauge pressure)； Additionally, CO2 levels should not be lowered too much to avoid excessive reduction of the catalyst, which would result in a reduction of the active interface between CuO and Cu. Generally, the volume fraction of CO2 should be kept at around 5.0%–12%. An excess amount can lead to incomplete reduction of the catalyst. As for what CO2 reacts with, it should be impossible. Because during normal production, both the CO2 partial pressure and the reaction temperature are more suitable than those during reduction.
What is pure hydrogen reduction? I’ve used C302 XNC-98 as well as products from Southern; in all cases it was recommended to use pure hydrogen for reduction. In theory, if it’s not pure, wouldn’t that result in CO2? How does CO2 affect it? Is there any relevant information?
Reply to 5# lizhaoye: That is caused by carbonates. When manufacturing the catalyst, precipitation pressing is required. During co-firing, it’s impossible for it to cause a complete delay.
It’s mainly this question: why restrict CO2? What is the mechanism of action?