Solvay is a Belgian multinational chemical company established in 1863, with its headquarters located in Neder-Over-Heembeek, Brussels, Belgium.

Since the end of 2023, following its demerger with the creation of the new Syensqo entity, Solvay has specialized in essential chemistry and employs over 9,000 people in 40 countries.

[12][needs independent confirmation] It was formerly also active in pharmaceuticals, but agreed to sell that entire division to Abbott Labs for €4.5 billion in September 2009,[13] a deal completed in February 2010.

In April 2011, the firm agreed to the €3.4 billion acquisition of French-based chemicals company Rhodia[14] which was completed in September 2011.

[29] New generation lithium batteries for hybrid vehicles components make use of Solvay fluorinated polymers in order to reduce carbon dioxide emissions.

[32] Solvay Specialty Polymers USA, LLC is currently under litigation for its per- and polyfluoroalkyl substances (PFAS) contamination of water sources and soil.

PFAS, a group of more than 4,000 compounds used in nonstick cookware, stain-resistant fabrics, firefighting foam and a range of other products,[33] do not break down in the environment, and therefore accumulate in the body.