The pore diameter
Molecular sieves are usually obtained with sodium as counterions after production. The pore diameter is then 4 angstroms. In order to make the adsorption even more selective compared to water, the molecular sieve is converted into the potassium form via an ion exchange. The pore diameter drops to 3 angstroms. The remaining portion of sodium zeolite should remain minimal.
The wetting properties
Depending on the washing process and the ion concentration on the surface of the molecular sieves, the dispersing properties, the influence of viscosity and the settling behavior can fluctuate greatly. Reproducibility can only be ensured by optimal process control.
A high number of foreign ions such as iron (III) has a negative effect on the storage stability of polyols. Through catalytic processes they age faster and the pot life decreases.
Finma-Sorb 430 PR does not show this problem. We only use products with a high degree of purity.