Why catalysts are sensitive to water
Thread Content
In high-temperature gas-solid catalytic reactions, the presence of water (steam) can easily lead to catalyst sintering. However, catalysts used in many gas-liquid phase reactions are also sensitive to water. What is the reason for this? Is it because water easily adsorbs in the micropores of the catalyst, preventing gases from entering the catalyst’s pore channels? This post was last edited by zxh6267 on 2009-3-25 13:18.]
1. Water vapor enters the catalyst pores, causing thermal degradation of the catalyst. 2. Hydrothermal aging of the catalyst leads to a decrease in its activity, and this effect is irreversible
When water comes into contact with a high-temperature catalyst and vaporizes rapidly, it causes the catalyst particles to break apart, a phenomenon known as catalyst thermal collapse.
A large temperature difference can cause the hot catalyst to burst
The effect of water on catalysts should be analyzed on a case-by-case basis; there are many reasons for this, including those mentioned above, as well as potential stability issues of the catalyst in the presence of water. It’s hard to say without specifying the particular reaction. :)
Not necessarily; ZSM-5 catalysts used in hydration reactions are not sensitive to water – it mainly depends on their application
There are various reasons for deactivation: 1. For metal catalysts, surface oxidation is an important cause of deactivation； 2. For some materials such as molecular sieves, catalytic materials tend to have their structure collapse in the presence of water and high temperatures ； 3. In reactions that take place at high temperatures in an acidic medium, the loss of active components is also a significant factor ；
What about the hydrogenation catalysts for carbon 2 and carbon 3? Is the fear of water related to concerns about palladium being oxidized? Is there such a thing as water blocking the channels?