The largest emitter of non-energy process emissions is OPC which is responsible for 5.5% of global greenhouse gas emissions. OPC is produced by thermally decomposing limestone into waste carbon dioxide and lime. The lime is further heated with a source of alumina, silica, and iron oxides to form OPC. This process requires temperatures of at least 1450 C.

Hydrogen which is responsible for ~2% of global greenhouse gas emissions is currently made by reacting water with natural gas at elevated temperatures to form waste carbon dioxide and hydrogen gas.

Responsible for ~6% of global greenhouse gas emissions, steel is made by burning petroleum coke in an oxygen deficient environment to make carbon monoxide which is then reacted with molten iron ore to make carbon dioxide and pig iron (carbon-rich iron). Forced air is then used to oxidize most of the remaining carbon in the pig iron to carbon dioxide to make the final steel product.

Aluminum production is responsible for about 1% of global greenhouse gas emissions. Aluminum ore (alumina) is extracted from the mineral bauxite via a heated pressure reactor. It is then put into a molten salt electrolyzer where aluminum metal and reactive oxygen species are produced at the cathode. The oxygen reacts with the graphite anode to produce carbon dioxide.