US Patent 7767192 - Molecular sieve nanocrystals

http://ip.com/patent/US7767192

Purification of petroleum products often require sieves which filter gases on a molecular level. This patent from ExxonMobile teaches a nanocrystalline sieve for improved molecular separation. Claim 1 reads:

1. A molecular sieve comprising single crystals or agglomerates, the crystals or agglomerates having an average largest dimension of 100 nm or less which molecular sieve has a crystal or agglomerate size distribution such that the variance in the longest dimension is less than 15% of the average longest dimension, and is capable of forming a stable colloidal suspension.