Hydrocarbon Separations in a Metal-Organic Framework with Open Iron(II) Coordination Sites

TLDR

Petroleum processing yields a mixture of saturated and unsaturated hydrocarbons, which are currently separated mainly by distillation. The study proposes a sorbent or membrane-based separation to achieve significant energy savings. Neutron diffraction identified iron center binding motifs that selectively capture olefins while allowing saturated hydrocarbons to pass. The iron‑based MOF demonstrated efficient sorption‑based separation of ethane/ethylene, propane/propylene, and other light hydrocarbons. Bloch et al.

Abstract

An Iron Separator Petroleum processing initially yields a mixture of saturated and unsaturated hydrocarbons—the feedstocks for fuels, plastics, pharmaceuticals, and a wide range of other commercial products. At present, distillation is the primary means of separating the components of this mixture. A sorbent or membrane-based approach to separation could reap substantial energy savings. Bloch et al. (p. 1606 ) found that an iron-based metal organic framework material shows promise for very efficient sorption-based separation of ethane and ethylene, propane and propylene, and several other light hydrocarbon mixtures. Neutron diffraction directly revealed the binding motifs at the iron centers that selectively pinned down the olefins while the saturated hydrocarbons passed by.