Use of zinc diphenyl as alkylation inhibitor in ligand-complexing process

In processes in which liquid sorbents that are solutions in an aromatic hydrocarbon or halogenated aromatic hydrocarbon of a bimetallic salt complex having the generic formula MIMIIXn.Aromatic, wherein MI is Group I-B metal, MII is a Group III-A metal, X is halogen, n is the sum of the valences of MI and MII, and Aromatic is a monocyclic aromatic hydrocarbon or halogenated aromatic hydrocarbon are used to separate complexible ligands from a gas feedstream that comprises an olefin having 2 or 3 carbon atoms, alkylation of the aromatic hydrocarbon or halogenated aromatic hydrocarbon is inhibited by incorporating in the liquid sorbent a small amount of zinc diphenyl.