Crude oil turns cheap porous membrane into a sieve to refine itself without heat

Nature, Published online: 24 June 2026; doi:10.1038/d41586-026-01896-9

An inexpensive, porous polymer membrane helps to separate raw crude oil, without heat or selective coating. Heavy hydrocarbons self-assemble inside the pores to create channels that are likely to be less than 2 nanometres wide, enriching the resulting permeate mix into light, ‘naphtha range’ hydrocarbons with 30% less energy cost and carbon dioxide emissions than conventional distillation.