Steam Reforming

Summary: Steam reforming is the industrial process that produces hydrogen (H₂) from methane (CH₄) and steam. It is the primary source of hydrogen for the Haber process. Tags: igcse chemistry hydrogen industrial keyword Created: 2026-07-14 Last Updated: 2026-07-14

Steam reforming is the principal industrial method for producing hydrogen gas, in which methane (natural gas, CH₄) reacts with steam (H₂O) at high temperature (700-1000 degrees Celsius) and moderate pressure over a nickel catalyst to yield carbon monoxide and hydrogen gas: CH₄ + H₂O → CO + 3H₂. A secondary water-gas shift reaction then converts the carbon monoxide with additional steam into carbon dioxide and more hydrogen (CO + H₂O → CO₂ + H₂), giving an overall stoichiometry of CH₄ + 2H₂O → CO₂ + 4H₂ — four moles of hydrogen for every mole of methane consumed. The hydrogen produced by steam reforming serves as the primary feedstock for the Haber process (N₂ + 3H₂ ⇌ 2NH₃), which manufactures ammonia essential for fertiliser production and underpins global food supply. While steam reforming is efficient and economically viable, it generates significant carbon dioxide as a by-product, meaning that most hydrogen currently manufactured is classified as “grey hydrogen” due to its carbon footprint unless carbon capture and storage (CCS) technology is employed, in which case it is termed “blue hydrogen.” For IGCSE, students should know the overall reaction equation, the reaction conditions (high temperature, nickel catalyst), and the crucial connection between steam reforming and the Haber process for ammonia synthesis.

Key term — IGCSE Chemistry (0620/0971) glossary.