C1 chemistry

Methanol is the precursor to acetic acid, dimethyl ether, formaldehyde, and many methyl compounds (esters, amines, halides).

A larger scale application is methanol to olefins, which produces ethylene and propylene.

Methane is often partially converted to carbon monoxide for utilization in Fischer-Tropsch processes.

Of interest for upgrading methane is its oxidative coupling: Conversion of carbon dioxide to unsaturated hydrocarbons via electrochemical reduction is a hopeful avenue of research, but no stable and economic technology yet has been developed.

[4] In photosynthesis, carbon dioxide and water is converted to sugars (and O2), the energy for this (thermally) uphill reaction being provided by sunlight.