... Appearance: Clear, colorless to pale yellow aqueous soluti 2-Phosphonobutane -1,2,4-Tricarboxylic Acid(PBTCA)CAS No. 37971-36- ... °C) g/cm31.27 minpH(1% water solution)1.5~2.0Fe ppm10.0 maxChloride ppm10.0 maxTurbidity (NTU)10.0 ... 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 ...