... , colorless to pale yellow aqueous soluti 2-Phosphonobutane -1,2,4-Tricarboxylic Acid(PBTCA)CAS No. 37971-36 ... and metal detergent.PBTCA is usually used together with zinc salt, copolymer, organophosphine, imidazole and ... with water.Synonyms:PBTCA;PBTC;PHOSPHONOBUTANE TRICARBOXYLIC ACID;2-Phosphonobutane -1,2,4-Tricarboxylic Acid;2-Phosphonobutane-1,2,4-tricarboxylic acid PBTC; 2-Phosphonobutane -1,2,4 ...