Hydrogen peroxide

Hydrogen peroxide emerged in 1818 not because Louis Jacques Thénard was uniquely brilliant but because three prerequisites had converged in Paris: barium peroxide from oxygen chemistry experiments, concentrated mineral acids from industrial production, and scientific understanding that compounds could contain varying oxygen levels. On July 27, 1818, Thénard presented his findings to the Académie des Sciences: reacting barium peroxide with nitric acid produced a colorless liquid that decomposed into water and oxygen—H₂O₂. He named it 'eau oxygénée' (oxygenated water). The chemistry was knowable from existing oxygen theory. The reagents were available from industrial synthesis. What was new was recognizing this unstable intermediate as useful.

The molecule itself is ancient. Hydrogen peroxide appears naturally in rainwater, snow, and human cells. White blood cells produce it to kill bacteria. Plants synthesize it as defense against pathogens. Biology discovered it billions of years before Thénard. What Thénard contributed was industrial synthesis—producing H₂O₂ at scale from barium peroxide and hydrochloric acid, then adding sulfuric acid to precipitate barium sulfate, leaving pure hydrogen peroxide in solution. The method worked but required expensive barium compounds.

Commercial production emerged in the 1890s using electrolysis, then shifted to anthraquinone oxidation in the 1930s—the process still dominant in 2025. Air oxidizes anthraquinone to produce H₂O₂; the anthraquinone regenerates for reuse. The method is efficient: 95 percent of global hydrogen peroxide comes from anthraquinone processes. The molecule Thénard isolated in 1818 became a $3.68 billion industry in 2025, projected to reach $5.74 billion by 2033 at 5.7 percent CAGR.

What hydrogen peroxide enabled was unprecedented versatility. Bleaching accounts for 35.3 percent of the market—paper mills and textile factories use it instead of chlorine because it degrades into water and oxygen, not toxic chlorinated byproducts. A paper mill in Sweden switched from chlorine to hydrogen peroxide in the 1990s, eliminating dioxin discharge into rivers while maintaining whiteness standards. The chemical does the same job without environmental persistence.

Disinfection represents the fastest-growing segment, expanding at 6.7 percent CAGR from 2025 to 2030. Municipal water treatment plants add hydrogen peroxide to eliminate pathogens without residual chemicals. COVID-19 accelerated adoption—hospitals used vaporized H₂O₂ to sterilize N95 masks for reuse when supplies collapsed. The molecule kills bacteria, viruses, fungi by oxidizing their cellular components, then decomposes into harmless water and oxygen within hours.

Rocket propulsion uses concentrated grades above 90 percent. The German V-2 rocket in WWII used hydrogen peroxide to drive turbopumps feeding fuel to combustion chambers. Modern rockets still use it—SpaceX's early Falcon 1 used H₂O₂ in its first-stage turbopump. Submarines use it for air-independent propulsion: decomposing H₂O₂ releases oxygen for combustion without surfacing. The U-boat U-1407, captured in 1945, ran on hydrogen peroxide power—submarines could stay submerged for weeks.

Path dependence explains why the anthraquinone process persists despite newer methods. Once chemical plants invested billions in anthraquinone infrastructure—reactors, regeneration systems, distribution networks—switching to electrochemical production (which uses only water and electricity) requires scrapping existing capital. The incumbent process is mature, reliable, and profitable. Innovation happens at the margins: optimizing catalysts, improving energy efficiency. But the 1930s anthraquinone chemistry remains standard because replacement costs exceed benefits.

The conditions that created hydrogen peroxide's utility endure: industries require oxidizing agents that decompose cleanly, medicine needs disinfectants that don't persist in tissue, and propulsion demands concentrated energy in compact form. The molecule Thénard synthesized from barium peroxide in 1818 serves all three. It persists because chemistry persists: two oxygen atoms bonded to two hydrogen atoms decompose exothermically into water and oxygen. Biology evolved this molecule for cellular defense. Thénard learned to make it in bulk. The $3.68 billion market is biology's chemistry, industrialized.