Ernest Solvay was born in Rebecq-Rognon, near Brussels, Belgium, to a family of industrial chemists. Although his only formal education was at local schools, young Solvay read and experimented widely in chemistry and electricity. He joined his father's salt-making business, and then, at age twenty-one, went to work with his uncle at a gasworks factory near Brussels.

Solvay began experimenting with the ammonia-soda reaction as a means of producing soda ash, which was then in great demand by the glass and soap industries. Most soda ash at the time was produced by the Leblanc process of converting common salt, a method which was expensive and created unusable byproducts. Solvay solved the practical problems of conducting the ammonia-soda process on a large scale, unaware that many chemists had tried and failed to do this over the past fifty years. He devised carbonating towers, which allowed large amounts of ammonia, salt solution, and carbon dioxide to be mixed; his process also allowed the recovery of expensive ammonia, which could then be reused.

Solvay patented his process in 1801 and founded a company with his brother, Alfred. They built a factory in 1863 and began commercial production of soda ash, using the Solvay process in l865. Solvay protected his process with many patents, but offered other manufacturers licensing rights to use his technology. By 1890 he had established plants in many foreign countries.

By the end of the 1800s the Solvay process produced most of the world's soda ash. Solvay became very wealthy as a result, and he used his money to endow schools and, in particular, to found he Solvay International Institutes of Chemistry, of Physics, and of Sociology. These institutes held well respected international conferences; those on physics were particularly noted for their inquiries into atomic structure and quantum mechanics. Solvay died in Brussels in 1922.