▎ 摘　　要

NOVELTY - For dehydration of product, graphene oxide membrane is used. The graphene oxide membrane comprises a layer of graphene oxide supported on a layer of porous membrane. USE - For dehydration of a product and separation of water from product by gas phase separation or pervaporation in detector system. The product is fermentation broth or has been extracted from a fermentation broth (claimed). ADVANTAGE - The membrane exhibits permeation characteristics that allow passage of water and, in some circumstances, other small polar solvents, such as methanol, ethanol and propanol whilst remaining completely impermeable to other fluids such as gases and liquids. The membrane is effective at wider range of conditions and more selective than existing technologies. The membrane uses a material that is cheaper and/or easier to prepare in bulk than existing technologies; is more efficient, in terms of yield or energy input than existing technologies; is durable and has good longevity, this allows material to be reused and/or recycled; and is particularly relevant for industrial uses. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) separating water from product involving contacting mixture of water and product with first surface of the graphene oxide membrane, and removing water from second surface of the composite material; and (2) composite semi-permeable membrane in the form of laminar structure, comprising at least a layer of graphene oxide and a layer of porous support.