Carl F. Dahl

Carl Friedrich Dahl (1849–1902) was a German chemist who first developed the kraft (sulfate) pulping process, the dominant method of chemical pulping used in modern papermaking.

Dahl worked in Danzig (then part of Prussia, now Gdańsk, Poland), an important Baltic port with a developing paper and cellulose industry. In 1884, he received U.S. Patent No. 296,935 for a process that used sodium sulfate in place of soda ash in the chemical recovery cycle of a soda pulping system. The resulting cooking liquor contained sodium sulfide along with caustic soda, producing significantly stronger pulp fibers than the soda process alone.