Why is it necessary to keep carbon monoxide and carbon dioxide levels below 20 ppm in the hydrogen mixture? What is the underlying principle behind this? and the hazards, thank you
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What is the specific principle behind controlling carbon monoxide and carbon dioxide levels at less than 20 ppm in the hydrogen mixture? and the hazards, thank you
What kind of process do you use? It’s probably to protect the subsequent catalysts
1. At temperatures of 200–350°C, CO, CO2 react with hydrogen to produce methane; this process not only consumes hydrogen but also results in an increase in temperature； 2. During startup and shutdown phases, at low temperatures, CO reacts with the nickel components in the catalyst to form nickel carbonyl, resulting in catalyst deactivation ； 3. CO2 also reacts with the reaction products to form calcium bicarbonate, which blocks high-pressure heat exchange equipment and affects heat exchange efficiency ； 4. Additionally, the new hydrogen contains CO and CO2, which reduces the purity of the recycled hydrogen.
This is mainly because CO and CO2 readily undergo methanation reactions with hydrogen in the first bed; these methanation reactions are exothermic, which can easily lead to a rise in temperature in the bed
This post was last edited by sdwfsgyykai on 2019-5-20 11:40. There is something called the methanation reaction
Prevent overheating during normal operation due to methanation, and prevent the formation of highly toxic nickel carbonyl with the catalyst Ni during shutdown
At approximately what temperature does the reaction between CO and nickel to form nickel carbonyl occur?