Adsorbent structures for removal of water and fuel contaminants in engine oil

摘要

Devices and methods for removal of condensed, blow-by contaminants with small molecular dimensions from the circulating lubricating engine oil of internal combustion engines, including automotive engines, with a positive crankcase ventilation system are disclosed. These condensable blow-by contaminants include water, alcohols and hydrocarbons with preponderantly seven or fewer carbon atoms. A macroporous structure comprising alumino-silicate particles with micro-pores is at least partially immersed in the circulating oil. The micro-pores are sized to adsorb the small, condensed, blow-by, contaminant molecules but not the larger oil molecules. The particles may be multi-layered, with an inner layer adapted for adsorption of polar molecules. Adsorption is most extensive at lower oil temperatures and decreases as the oil temperature increases. Thus at low temperatures the contaminant molecules may be adsorbed, removed from the oil and temporarily stored in the micropores. At high temperatures some of the contaminants will desorb and be re-incorporated in the oil. The desorbed contaminants will be carried with the higher temperature oil into the engine crankcase where they may vaporize and be removed by the engine positive crankcase ventilation system.