Production of synthesis gas by steam reforming

This dossier concerns only the production of hydrogen from light feedstocks by steam reforming, and does not cover production by partial oxidation ( – POX) of heavy feedstocks, or by coal gasification [J 5 200] .

The term synthesis gas can be interpreted very broadly. In fact, it is generally considered to apply to gas mixtures that can be combined to synthesize organic compounds or ammonia.

Syngas systematically contains two or more of nature's four most common elements: carbon, oxygen, hydrogen and nitrogen. Oxygen is almost always combined with carbon in the form of carbon monoxide or carbon dioxide.

Hydrogen is the essential component of syngas. Nitrogen is essential for ammonia synthesis, but would be inert in the case of organic product synthesis.

Hydrocarbons (natural gas or, more rarely, oil cuts) are the main source of synthesis gas.

The lightest raw materials undergo catalytic conversion, using steam as the oxidizing agent, known as steam reforming. Heavier feedstocks (oil residues, coal, biomass, etc.) are converted using oxygen, known as partial oxidation or gasification.

After starting up in the 1980s, these conversion processes became marginal, but have seen renewed interest in recent years, either in specific geographical contexts (China, India in the coming years), or because of the scarcity of future outlets for oil residues (fuels with very high sulfur content, petroleum coke...).

Syngas production by partial oxidation of heavy fuels and coal gasification is the subject of [J 5 440] and [J 5 200] .