1- Hydroxyethane-1,1-diphosphonic acid

A typical compound of the first class is 1-hydroxyethane-1,1-diphosphonic acid (HEDP, DEQUEST 2010), which is often employed in practical applications. As shown in Fig. 3-97, this compound may be analyzed in the same run with other aminopolyphosphonic acids. 

HEDP 1 hydroxyethane-( 1,1 -diphosphonic acid) or i-hydroxyethane-( 1,2-diphosphonic acid) 156, 2... 

Chiarizia et al. [136] studied the application of the SLM for the removal of U(VI) from synthetic and industrial wastewaters. Bis(2,4,4-trimethylpentyl) phosphinic acid (Cyanex(TM) 272) was used as the carrier, w-dodecane was used as the diluent, and hollow polypropylene fibers were used as the support for the hoUow-fiber SLM. This setup was chosen based on the selectivity for U(VI) over Ca2+ and Mg-. 1-hydroxyethane-1, 1-diphosphonic acid was added into the stripping phase as a masking agent that can increase the permeation rate by keeping the activity of LJ(VI) in that phase close to zero [130]. 

The relationships described above have been used to expand the number of known phase-forming salts. Salts whose anions have large — AGhyd values should salt out PEG-2000. This information was used to predict the ability of new salts to form ABSs, such as those formed with vanadate, chromate, molybdate, tungstate, citrate, and HEDPA (1-hydroxyethane-1,1-diphosphonic acid) tetraanion (Fig. 5 [8,43 ). This led directly to the MoO /TcO/r separation process discussed in Sec. VI. A. 

Fig. 1 A) Separation of phosphates and phosphonic acids B) absorption plots of track 5 and track 8. PjOl (1), PjOio (2), P20t (3), POl (4), mixture 1 (5), aminotrimethylene-phosphonic acid (6), l-hydroxyethane-l,l-diphosphonic acid (7), mixture II (8).

Fig. 3-104. Separation of polyphosphonic acids upon application of phosphorus-specific detection. - Separator column IonPac AS7 eluent 0.17 mol/L KC1 + 0.0032 mol/L EDTA, pH 5.1 flow rate 0.5 mL/min detection photometry at 410 nm after hydrolysis and derivatization with vana-date/molybdate injection 50 pL, l-hydroxyethane-l,l-diphosphonic acid (HEDP), aminotris-(methylenephosphonic acid) (ATMP), ethylenediamine-tetramethylenephosphonic acid (EDTP), l,l-diphosphonopropane-2,3-dicarboxylic acid (DPD), and 2-phosphonobutane-l,2,4-tricarboxylic add (PBTC) (taken from [84]).

Leroux, Y, El Manouni, D., Safsaf, A., Neuman, A., Gillier, H., and Burgada, R., Structural smdy of l-hydroxyethane-l,l -diphosphonic acid tetramethyl ester and of l-hydroxy-l-phenyhnethane-l, -diphosphonic acid tetramethyl ester. Phosphorus, Sulfur Silicon Relat. Elem., 56, 95, 1991. 

Additional examples of functionalized magnetic materials described in the literature for specific appHcations are summarized in this section. Magnetic microparticles with embedded silicotitanate have shown excellent adsorption ability for radioactive cesium isotope ( Cs) from HEDPA (l-hydroxyethane-l,l-diphosphonic acid), although dissolution of magnetite in acidic solutions in the regeneration step leads to a decrease in magnetic susceptibility (Kaminski and Nunez, 2002). 

The chelating agents used by researchers to enhance electrochemical remediation include EDTA, citric acid, oxalic acid, ammonia, iodide/iodine, potassium iodide solution, sodium chloride solution, l-hydroxyethane-l,l-diphosphonic acid (HEDPA), HPCD, and so on. EDTA is the most frequently used chelating agent in electrochemical remediation. The complexation chemistry of EDTA is briefly outlined as an illustration. 

This is illustrated in Fig. 5, in which the data of Felhosi and coworkers on the effect of Zn + ions on the corrosion inhibition of steel by 1-hydroxyethane-l, 1-diphosphonic acid (HEDP) are shown [9). 

CAS 3794-83-0 EINECS/ELINCS 223-267-7 Synonyms Ethane-1-hydroxy-1,1-diphosphonic acid, tetrasodium salt (1-Flydroxyethylidene) bisphosphonic acid, tetrasodium salt (1-Fly-droxyethylidene) diphosphonic acid, tetrasodium salt 1-Flydroxyeth-ylidene-1,1 -diphosphonic acid, tetrasodium salt NaiFIEDP Phosphonic acid, (1-hydroxyethylidene) bis-, tetrasodium salt Tetrasodium 1-hydroxyethane-1,1 -diphosphonate Tetrasodium (1 -hydroxyethylidene) bisphosphonate Tetrasodium 1 -hydroxyethylidene-1,1 -diphosphonate Classification Diphosphonic acid deriv. 

Hydroxyethane-1,1-diyl) diphosphonic acid disodium salt (1-Hydrxyethylidene) diphosphonic acid disodium salt Phosponic acid, (1-hydroxyethylidene) di-, disodium salt Sodium ethidronate Sodium ethydronate Sodium etidronate Empirical C2H6O7P2 2Na Properties M.w. 250.00... 

Hydroxyethane-1,1-diyl) diphosphonic acid disodium salt. See,Disodium etidronate... 

Phosphonic acid, (1-hydroxyethylidene) bis-, tetrasodium salt Tetrasodium 1-hydroxyethane-1,1-diphosphonate Tetrasodium (1-hydroxyethylidene) bisphosphonate Tetrasodium 1-hydroxyethylidene-1,1-diphosphonate Ciassification Diphosphonic acid deriv. 

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