Richard Willstätter built a gas mask filter in five weeks

Person: Richard Willstätter
Lived: 1872–1942
Field: Organic chemistry
From: German

The story

In 1912 Richard Willstätter moved to Berlin to direct the new Kaiser Wilhelm Institute for Chemistry in Dahlem. Next door stood the institute for physical chemistry run by Fritz Haber, and the two directors became close friends. When the First World War began, the Dahlem institutes were pressed into war-related work, and Haber took charge of Germany's chemical warfare programme.

In 1915 Haber asked Willstätter to join in the development of poison gases. Willstätter would not work on poisons, but he agreed to work on protection. Haber needed a chemical absorption unit for gas masks that would protect soldiers against chlorine and phosgene, a severe respiratory poison.

In about five weeks Willstätter came up with a canister containing activated charcoal and hexamethylenetetramine, also known as urotropin. Charcoal had been used before, but hexamethylenetetramine was a new idea. When asked after the war how he had thought of so unusual a compound, he said that the idea had simply popped into his head. He and his co-workers developed a three-layer filter that absorbed the enemy's gases, and thirty million were manufactured by 1917. He received the Iron Cross, Second Class, for the work.

The months were among the hardest of his life. In the spring of 1915 his ten-year-old son, Ludwig, died suddenly, and Willstätter later wrote that his memory of the following months was blurred. In November, while he was still working on gas masks, he learned that he had been awarded the 1915 Nobel Prize in Chemistry for his research on plant pigments. He also worked with Friedrich Bergius on breaking down cellulose into sugar, the basis of what became known as the Bergius-Willstätter process.

The design showed how quickly a chemist with deep practical skill could solve an urgent problem. It was also an example of a scientist drawing a moral line in wartime: he would apply his chemistry to defending people, but not to harming them. He showed similar resolve in 1924, when he gave up his Munich chair to protest antisemitism.

Why it matters

Willstätter chose to save lives rather than take them, and his filter protected soldiers from some of the most feared weapons of the war.

About Richard Willstätter

Nobel-winning chemist who unravelled chlorophyll and the colours of flowers, refused to convert, resigned his chair in protest at antisemitism and died a refugee in Switzerland.

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Richard Willstätter

1872–1942 · Organic chemistry

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