The Role of Plasmas in the Electrification and Decarbonization of Chemical Manufacturing

Chemical manufacturing is the foundation of supply chains that provide society with more than 96% of all goods. It consumes 10% of global energy production, nearly all in thermochemical processes fueled by fossil fuel combustion, contributing 5.5% of the global CO₂ emissions and thus accelerating anthropogenic climate change. Chemical manufacturing plants comprise a network of reactors to synthesize mixtures of chemicals and separation units such as distillation to obtain purified products. Any energy needed but not produced by exothermic chemical reactors is supplied by fossil fuel combustion (86%) or brown electricity (14%). Recent decarbonization goals are driving the rethinking of this chemical manufacturing paradigm and its potential replacement with decarbonized production schemes powered directly by clean electricity. One of the options is to replace thermochemical reactors with electrically driven non-thermal plasma processes. We critically assessed technical, economic, and environmental factors to evaluate the prospects of this impending paradigm shift. Among bulk organic chemicals, we focused on ethylene, BTX (Benzene, Toluene, Xylene), and propylene as the highest volume chemicals by the energy consumed and CO₂ emitted: they account for >50% of the energy consumed (and thus CO₂ emitted) in the manufacture of basic organic chemical commodities. Specifically, we review the state-of-the-art production method, its economics and CO₂ emission, potential options for electrifying its manufacturing, including plasmas, the impacts of carbon pricing on their deployment, and the technological gaps holding back the deployment of these options. We aim at trying to answer the questions of (1) whether plasma reactors can replace thermochemical reactors in the economical manufacture of chemicals, (2) what chemicals should be targeted, and (3) what basic and applied plasma research is needed to make plasma production of bulk organic chemicals possible.