Aluminium anodizing pore membrane

[Stormer]

TL;DR Summary

Using Aluminium anodizing pores as filter membrane.

When anodizing aluminium (or Titanium) a dense hexagonal pattern of microscopic pores is formed, and you can get a pretty high aspect ratio with them. But the illustrations always show the oxide layer with pores on top of a pure aluminium layer. But can you oxidize a thin sheet of material so that the pores go all the way trough so you can use this as a sort of filtering membrane? And if so how thin of a sheet do you need to use? Or can you use a enchant that etch the pure aluminium away, but don't etch the oxide layer?

 

[TeethWhitener]

Summary:: Using Aluminium anodizing pores as filter membrane.

But can you oxidize a thin sheet of material so that the pores go all the way trough so you can use this as a sort of filtering membrane?

Yes:
https://www.sigmaaldrich.com/labware/labware-products.html?TablePage=109501875

 

[Stormer]

Yes:
https://www.sigmaaldrich.com/labware/labware-products.html?TablePage=109501875

But how is it made? With etching after the anodizing , or just anodizing all the way trough a thin sheet?