Removal of Surfactant
The traditional method is calcination. The inorganic – surfactant complex is heated to high temperatures for extended periods under a flow of air, oxygen or nitrogen, to "burn off" the surfactant molecules. Forceful conditions are required to break the strong electrostatic bonds between the micelles and the inorganic species.
The non-ionic templating approach allows the removal of the surfactant by solvent extraction, as the hydrogen bonding involves is more easily broken. The surfactant is recovered and therefore can be recycled.
Other methods include plasma and super-critical fluid extraction.
A recent journal published a paper detailing surfactant removal by ozone. This involves a highly exothermic process, which cannot currently be controlled. Treatment with ozone forms larger pores, with a decreased size distribution and increased order.
Large size distribution, low order Small size distribution, high order.