Homogeneous catalysis boosted by electrochemical recovery of precious metal complexes

A new, more efficient process to electrochemically recycle some homogeneous catalysts has been demonstrated by scientists in the US. The technique, which reversibly binds the metal complexes to a polymer, can recover several industrially important and precious metal catalysts.

In homogeneous catalysis the active sites of the catalyst are fully dispersed into the reaction mixture. This gives homogeneous catalysts a kinetic advantage over heterogeneous catalysts as they are readily available to the reactants, and a selectivity advantage as they can manipulate reaction pathways with more sophistication. Homogeneity is a double-edged sword, however. The more intimately the catalyst disperses into a mixture, the harder it is to separate. As homogeneous catalysts are often precious metal complexes, effective recovery is often vital if a reaction is to be economically viable. This is one reason about three-quarters of processes in the chemical and petrochemical industries rely on heterogeneous catalysts instead of homogeneous ones, despite their advantages.