Abstract: Membranes of the invention comprise a hybrid silica film on a organic polymer support. The silica comprises organic bridging groups bound to two or more silicon atoms, in particular at least 1 of said organic bridging groups per 10 silicon atoms. The membranes can be produced by dry chemistry processes, in particular plasma-enhanced vapour deposition of bridged silane precursors, or by wet chemistry involving hydrolysis of the bridged silane precursors. The membranes are inexpensive and efficient for separation of small molecules and filtration processes.

Abstract: Selective retaining a relatively hydrophilic molecule from a mixture of a relatively hydrophobic molecule and the relatively hydrophilic molecule can be achieved using a hydrophobic, microporous hybrid membrane based on silica, wherein at least 25% of the silicon atoms is bound to a bridging C1-C12-hyrdocarbylene group. The average number of carbon atoms of the bridging groups and any additional monovalent organic groups, taken together, is at least 3.5. The membrane can be part of a production facility for separating alcohol/water mixtures.