US Patent 7488876 - Nitronium ion separation of carbon nanotubes

http://www.freepatentsonline.com/7488876.html

This patent from Samsung Corning Precision Glass teaches a method of semiconductor/metallic carbon nanotube separation based on nitronium ions. Claim 1 reads:

1. A method of separating semiconducting type carbon nanotubes from a mixture of semiconducting and metallic carbon nanotubes, comprising the steps of:

1) treating the carbon nanotube mixture with an organic solution containing nitronium ions,

2) filtering the resulting mixture to recover remaining solids, and

3) heat-treating the solids.