Patent ID: 8016125

Claim:
A chemical filter for filtering oil within an internal combustion engine lubrication system to immobilize combustion acids, the chemical filter comprising: filtration media including: (a) a fibrous web; (b) particles disposed within the fibrous web, said particles including internal pores formed within individual particles and interstitial pores formed between adjacent particles, the internal pores and the interstitial pores collectively defining filtration media pores; and (c) a strong base material associated with at least some of the internal pores and exposed to oil flowing through the chemical filter, wherein the strong base material associated with the filtration media pores has a surface area greater than or equal to 25 m 2 /gm that is derived from filtration media pores having a median pore diameter between 60 Angstroms and 3,000 Angstroms as measured by mercury intrusion porosimetry and the strong base material is situated so as to interact with the oil within said engine lubrication system during use of said chemical filter such that said strong base material interacts with combustion acid-weak base complexes in said oil to immobilize said combustion acids and remove said combustion acids from the oil.