The Collaborative International Dictionary of English v.0.48:

Beneficiate \Ben`e*fi"ci*ate\, v. t. [Sp. beneficiar to benefit,
   to work mines.] (Mining)
   To reduce (ores). -- Ben`e*fi`ci*a"tion (?), n.
   [1913 Webster]

WordNet (r) 3.0 (2006):

beneficiate
    v 1: process (ores or other raw materials), as by reduction