Use
Sublime it, then crystallise it from nitromethane or ethanol. If phenylmercuric halides are present, they can be converted to phenylmercuric hydroxide which, being much more soluble, remain in the alcohol or *benzene used for crystallisation. Thus, crude material (10g) is dissolved in warm ethanol (ca 150mL) and shaken with moist Ag2O (ca 10g) for 30minutes, then heated under reflux for 30minutes and filtered hot. Concentrating the filtrate by evaporation gives diphenylmercury, which is then recrystallised from *benzene [Blair et al. J Chem Soc 3174 1959]. [Beilstein 16 IV 1702.] TOXIC.