365: Chemistry for Life
DAY 122

Commercial Processes for Making Calcium Carbide and Acetylene

In 1892, Canadian Thomas L. Willson accidentally discovered the electric-arc process for preparing calcium carbide.

Credit: iStock

May 2, 1998, marked the 106th anniversary of an unexpected discovery in the village of Spray (now Eden), North Carolina, that proved to be a milestone in the history of the chemical industry. On that date, Thomas L. Willson, a struggling young Canadian inventor, accidentally discovered the processes for making calcium carbide and acetylene in commercial quantities.

Acetylene, when burned in air, gave a light far brighter than any in use at the time for home lighting. When burned with oxygen, it gave a flame that was 1000° C hotter than any other, leading to the development of commercial oxyacetylene welding and cutting. Most importantly, acetylene later became the starting material in the synthesis of hundreds of aliphatic organic chemicals used worldwide, particularly solvents, plastics, and synthetic rubber.

Thomas Leopold Willson (1860-1915), discoverer of these processes, was born in Princeton, Ontario, the grandson of John Willson, speaker of the United Canadian Assembly. He attended Hamilton Collegiate Institute; but after his father died, he withdrew from school to develop an arc-lighting system, the first seen at Hamilton. At age 22, he moved to the United States where he held various jobs in the mechanical and electrical trades before settling in Brooklyn, New York, in 1887. His work over the next three years resulted in six patents, which secured for him the rights in the United States for use of the electric-arc furnace in ore smelting. Aluminum metal was a primary target.

Visit National Historic Chemical Landmarks to read more about the discovery of processes for preparing calcium carbide and acetylene.

Excerpted with permission, National Historic Chemical Landmarks Program
www.acs.org/landmarks