Theoretical reaction rate for water electrolysis

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The discussion focuses on designing a process to convert carbon dioxide into methane using the Sabatier reaction, which requires hydrogen produced via water electrolysis. The user seeks to calculate the reaction speed to determine the reactor size but faces challenges due to the need for an experimentally derived reaction rate constant. They clarify that the electrolysis rate is determined by current, referencing the equation for hydrogen production. The conversation also confirms that "I" stands for current and "F" represents the Faraday constant. Understanding these parameters is crucial for optimizing the reaction process.
Erwin123
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So I'm designing a proces where carbondioxide is converted into methane using the Sabatier reaction. For this reaction hydrogen is required which I'm planning on producing using the electrolysis of water. But I'm having a problem where I need the speed of this reaction to determine the size of the reactor needed. Does anyone know how I can calculate this reaction speed without using experiments? Because the normal equation for reaction rate gives me a value with a reaction rate constant which is obtained experimentally (see the figure on the right for my derived equation for the reaction rate).
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I hope I can get an answer soon
 
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For an electrolysis, the rate is determined by the current. For the reaction
2H+ + 2e- → H2
dnH2/dt = I/2F
The factor of 2 is because 2 moles of electrons are consumed per mole of hydrogen gas produced.
 
mjc123 said:
For an electrolysis, the rate is determined by the current. For the reaction
2H+ + 2e- → H2
dnH2/dt = I/2F
The factor of 2 is because 2 moles of electrons are consumed per mole of hydrogen gas produced.
Thank you one more question what do the I and F stand for? Faraday constant and current of electricity?
 
Yes. Or current and Faraday constant respectively.
 
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