A mechanochemical method was used to treat a used evaporation tape, aiming at recovering the contained cobalt (Co) metal and achieving dechlorination non-thermally by dry grinding the tape only or cogrinding with calcium oxide (CaO), respectively. The induced mechanochemical reaction between Co and chlorine in the tape leads to the formation of cobalt chloride, which is water-soluble, offering a novel process to recover the metal from the tape. On the other hand, cogrinding with CaO allows the complete transformation of chlorine in the tape into water-soluble inorganic chloride. The mechanochernical dechlorination process was characterized by an XRD analysis, TG-DTA analysis, SEM photography, Raman analysis and quantitative measurement of the soluble compositions.