Process for concentrating small organic molecules from liquid or gaseous mixtures using a composite membrane comprising a fluoropolymer and hydrophobic siliceous particles

摘要

Process for concentrating at least one chemical from a liquid or gaseous feed mixture comprising the steps(a) contacting a liquid or gaseous feed mixture with a first surface of a composite membrane having two surfaces, wherein said feed mixture comprises- at least one gaseous or liquid diluent and- at least one chemical having a vapour pressure in pure form of 0.8 mbar or more at 20 °C,and wherein said composite membrane consists of(i) a matrix of a fluoropolymer in the form of fibrils, wherein said fluoropolymer has a content of tetrafluoroethylene repeating units of at least 90 mol-% relative to the total amount of repeating units,(ii) hydrophobic siliceous particles enmeshed into said matrix,(b) applying reduced pressure to the second surface of the composite membrane which is opposite to the first surface in contact with the feed mixture such that a permeate mixture is obtained on said second surface of the composite membrane, wherein said permeate mixture has a higher content of said at least one organic component and/or hydrogen than said feed mixture;(c) collecting said permeate mixture.