2-Phosphonobutane-1,2,4-tricarboxylic acid

2-Phosphonobutane-1,2,4-tricarboxylic acid (CAS 37971-36-1) is an organophosphonic acid supplied as a clear aqueous solution and registered under EC 253-733-5. It is commercially available under trade names including PBTCA, Bayhibit AM, Cublen P 50, and Dequest 7000. No E-code designation applies.

In cooling water and boiler systems, PBTCA inhibits scale formation by chelating calcium and magnesium ions while simultaneously stabilising zinc-based corrosion inhibitors across a broad pH range. In textile processing, it sequesters metal ions that would otherwise catalyse dye degradation, improving colour consistency and fabric quality.

PBTCA is supplied as an aqueous solution, typically at 50% active content, and falls under REACH registration requirements for EU supply. It is not listed under FCC or Ph.Eur. monographs. Standard packaging includes IBC containers and bulk tankers; buyers should confirm concentration grade and regional REACH compliance documentation prior to procurement.