Industrial chemistry's reliance on fuel-fired furnaces is one of the harder decarbonisation problems, because the heat involved is both intense and diffuse. Researchers at NUS have borrowed the operating principle of the incandescent lightbulb instead. Electricity passes through a thin metal filament that rapidly exceeds 1,200 degrees Celsius while the surrounding reactor body stays comparatively cool, so only the reaction zone is heated and the vessel itself can be small.
The work was led from the NUS Centre for Hydrogen and Carbon Innovations within the Department of Chemical and Biomolecular Engineering. Because the heat source is electrical, the reactor couples directly to renewable generation, which is where most of the emissions benefit comes from. The compactness follows from the same design choice: there is no need to bring a large thermal mass up to temperature, so reactor volume shrinks relative to conventional fired equipment.
Three applications have been demonstrated across separate papers. Ammonia decomposition achieved near-complete conversion to hydrogen in a far smaller reactor than conventional systems, reported in Nature Chemical Engineering. Polyethylene and polypropylene were broken down into chemical building blocks for new plastics, reported in Nature Communications. Methane conversion using separate temperature zones yielded valuable chemicals along with hydrogen, reported in Nature Sustainability.
That a single platform spans hydrogen carriers, circular plastics and natural gas upgrading is the point of interest for chemical engineers. These are usually treated as distinct process challenges with distinct hardware. A filament-heated architecture suggests they share a common requirement, namely localised high temperature delivered electrically, and the team is now exploring how the concept scales towards industrial duty.