Patent ID: 7601203

Claim:
A fuel stabilization unit comprising: a first vacuum stage for generating a first oxygen partial pressure differential across an oxygen permeable membrane; a second vacuum stage for generating a second oxygen partial pressure differential across the oxygen permeable membrane; said first vacuum stage comprising a first component, and said second vacuum stage comprising a second component, with said first and second components being different types of vacuum-creating components; a fuel passage defined through the first vacuum stage and the second vacuum stage; a first vacuum outlet connected to the first vacuum stage to remove oxygen from the first vacuum stage; a second vacuum outlet connected to the second vacuum stage to remove oxygen from the second vacuum stage, wherein the first vacuum outlet and the second vacuum outlet are separate; the second oxygen partial pressure differential is greater than the first oxygen partial pressure differential; the first vacuum stage and the second vacuum stage are separated from each other within the fuel stabilization unit; and said oxygen permeable membrane permits permeation of oxygen and nitrogen, but does not permit permeation of heavier fuel molecules.