STEP polymer degradation: Solar thermo-coupled electrochemical depolymerization of plastics to generate useful fuel plus abundant hydrogen

Electrochemical methods for materials recycling

“…126 As discussed in previous examples, pyrolysis, which is the most employed method of breaking down plastics, is extremely high energy, endothermic, requires temperatures up to 500 1C, and often requires a catalyst. [126][127][128][129] STEP uses solar energy to reduce that energy barrier and obtain higher yields with less harsh conditions. The process works by coupling oxidative carboncarbon bond breaking at the anode with hydrogen evolution at the cathode.…”

“…Jiang et al found that, by linking a solar panel to a photovoltaic (PV) module, they could use STEP to break down PP waste into hydrogen gas and light hydrocarbons. 129 A nickel wire electrode was used, and a mixture of NaOH and KOH was used as the electrolyte. A voltage of 1.5 V was applied for 4 hours, at a temperature of 350 1C, via a solar to thermal unit (heat concentrator).…”

“…Fig.11Solar-thermal-electrochemical process STEP (top) and pyrolysis (bottom) on waste polypropylene 129. …”

Rational Design of Chemical Catalysis for Plastic Recycling

“…Expanding the use of advanced recycling technologies is a promising approach to tackle the immense and urgent challenge of plastic wastes. 127,136,137 The meaning of the design and optimization of catalysis is not only to promote plastic degradation efficiency but also to provide more suitable and low-cost catalytic system for industry. In addition to the already industrialized thermocatalytic technology, the emerging photothermal, electro-and photocatalysis are expected to degrade plastic efficiently under mild conditions with lower energy consumptions and CO 2 emissions.…”

“…Expanding the use of advanced recycling technologies is a promising approach to tackle the immense and urgent challenge of plastic wastes. ,, The meaning of the design and optimization of catalysis is not only to promote plastic degradation efficiency but also to provide more suitable and low-cost catalytic system for industry. In addition to the already industrialized thermocatalytic technology, the emerging photothermal, electro- and photocatalysis are expected to degrade plastic efficiently under mild conditions with lower energy consumptions and CO 2 emissions. − However, the tandem catalytic system is also an efficient strategy to boost the degradation efficiency by another catalytic reaction. ,, The tandem systems can upcycle the waste plastic into various value-added products according to different reactions, which are an important future direction for plastic recycling.…”