Abstract: Introducing an additive into a crude oil may result in the crude oil having comparatively lower acid levels as compared to an otherwise identical crude oil absent the additive. The additive may include nanoparticles of metal oxides, oil soluble hydrogen donors, and/or heavy amines. The oil soluble hydrogen donors may be or include 1,2,3,4-tetrahydronaphthalene; 1,2,3,4-tetrahydrdroquinoline; 9,10-dihydroanthracene; 9,10-dihydrophenanthrene; and combinations thereof. The heavy amines may be or include alkyl amines, alkanolamines, polyethylene amines, polypropylene amines, and combinations thereof.