Born at Rebecq, an illness prevented him from going to university. He worked in his uncle's chemical factory from the age of 21.
In 1861, he developed the ammonia process for the manufacture of anhydrous sodium carbonate from table salt.
He established his first factory at Couillet in 1863 and further perfected the process until 1872, when he patented it. Soon, Solvay process plants were established in the United Kingdom, the United States, Germany and Austria. Today, about 70 Solvay process plants are still operational worldwide.
The exploitation of his patents brought Solvay considerable wealth, which he used for philantropic purposes, including the establishment of the Institute for Sociology at the University of Brussels, as well as international Institutes for Physics and Chemistry.
He was two times elected to the Belgian Senate and appointed Minister of State at the end of his life.
Solvay died at Ixelles.