an interesting way to generate energy without producing greenhouse gas by burning iron(https://spectrum.ieee.org/energywise/energy/renewables/iron-powder-passes-first-industrial-test-as-renewable-co2free-fuel). The article seems to suggest that a process can be developed to strip iron out of rust to burn it again, creating a green cycle that does not generate greenhouse gas. You want to compare the energy required to oxidize the metal vs. the energy required to de-rust from different methods to see if there is a net positive (meaning the energy we get from oxidizing the metal is more than the energy we need to de-rust and get back the metal). You also find the equation below to calculate the enthalpy for a reaction aA + bB → cC + dD: \Delta H_{T 2}=\Delta H_{T 1}+\int_{T 1}^{T 2} C p d T+\sum_{i} \Delta H_{p c i}
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