| 摘要 |
A method of raising the concentration of a liquid mixture utilizes osmotic distillation to transfer a volatile component from the mixture in contact with one side of a nonporous, preferably high free volumes, gas permeable membrane to a strip solution in contact with the other side of the membrane. Due to its nonporous nature the gas permeable membrane resists penetration and wetting by oily components that may be present in the feed mixture. Similarly, occlusion of the membrane by solids to resisted. Preferably, an amorphous copolymer of perfluoro-2,2-dimethyl-1,3-dioxole is useful for the gas permeable membrane. Osmotic distillation utilizing such high free volume, nonporous gas permeable membranes can concentrate difficult liquid mixtures such as pulpy fruit juices and especially, limonene-containing juices, for example, orange juice. The process can be operated at high flux for long durations between membrane cleanings. Additionally, less contamination of the strip solution into the feed mixture occurs to provide a high quality concentrate. |
