Is the terminal Si-OH in the framework of zeolite?
Si Al zeolite or molecular sieves.
Yes, usually it is located on the surface or defect site of the zeolite. It gives Bronsted acidity to the zeolite
Hello,
yes there are silanol groups in zeolites (see the answers above). But in most of the zeolites these are negligible. Because they only occur at the (outer) surface and at defects. But the outer surface do not dominate the properties of zeolites, they are mostly determined by the huge inner surface.
As it has been written before the acidity of Si-OH (terminal silanol) is clearly lower than the classical zeolitic Brønsted site Al-OH-Si (briding hydroxyl group).
Attached few papers regarding this topic.
Article A Study on the Surface Silanol Groups Developed by Hydrother...
Article State of the Art and Future Challenges of Zeolites as Catalysts
Article Reactivity of silanol groups on zeolite surfaces
Article Reactivity Theory of Zeolitic Br??nsted Acidic Sites
Article The Nature of Silanol Groups on the Surfaces of Silica, Modi...
- Badges
- Science topic