... . In lavation fields, it is used as chelating agent and metal detergent.PBTCA is usually used together with zinc salt, copolymer ... .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-Tricarboxylic Acid (PBTCA)