Phosphoric acid dibutyl

Acidic alkyl esters of phosphoric acid, of which dibutyl-phosphoric acid (HDBP) and di(2-ethylhexyl) phosphoric acid (HDEHP) are typical,... 

DCTA 1,2-diaminocyclohexane tetraacetic acid DBP dibutyl phosphoric acid DTP A diethylenetriamine pentaacetic acid DEHPA di-2-ethylhexyl phosphoric acid... 

The ZEALEX Process Researchers from KRI have shown that the zirconium salt of dibutyl phosphoric acid (ZS-HDBP) was soluble in Isopar-L in the presence of 30% TBP. This super PUREX solvent, known as ZEALEX, extracts actinides (Np-Am) together with lanthanides and other fission products, such as Ba, Cs, Fe, Mo, and Sr from nitric acid solutions. The extraction yields depend on both the molar ratio between Zr and HDBP in the 30% TBP/Isopar-L mixture and the concentration of HN03 (232). Trivalent transplutonium and lanthanide elements can be stripped together from the loaded ZEALEX solvent by a complexing solution, mixing ammonium carbonate, (NH4)2C03, and ethylenediamine-N.N.N. N -tetraacetic acid (EDTA). An optimized version of the process should allow the separation of... 

Zilberman, B.Y., Fedorov, Y.S., Shmidt, O.V., Goletskiy, N.D., Shiskin, D.N., Esymantovskiy, V.M., Rodionov, S.A., Egorova, O.N., Palenik, Y.V. 2007. Usage of dibutyl phosphoric acid and its zirconium salt for extraction of transplutonium elements and rare earths with their partitioning. Global 2007 Advanced Nuclear Fuel Cycles and Systems, September, Boise, ID. 

Hahn, H.T., Vander Wall, E.M. 1964. Complex formation in the dilute uranyl nitrate-nitric acid-dibutyl phosphoric acid-tributyl phosphate-amsco system. J. Inorg. Nucl. Chem. 26 191-192. 

For technical applications, knowledge of the irradiation behaviour of the Levextrel-TBP resin is important. A detailed study carried out at the Radiochemistry Institute of the Technical University, Munich(21,22), showed that with gamma irradiation the formation rate of dibutyl phosphoric acid (HDBP) and of "non-removable" acidic radiolysis products ("do-bads") is 2 to 5 times lower with Levextrel-TBP resin than with pure TBP the effect is attributed to the "scavanger" action of the aromatic groups in the matrix material. In summary, a high radiation resistance of the resin has become evident. 

Dibutyl phosphoric acid (HDBP) also dimerizes in nonpolar solvents and solutions of HDBP in kerosene contacting aqueous nitric acid equilibrate to produce (HDBP)2, HDBP-H2 0 and HDBP-HNOs in both phases. In addition, the organic phase contains (HDBP)2-H20 and the aqueous phase (Bu"0)2P02 (DBP ) in equilibrium with HOBR " Such equilibria complicate the stoichiometry of extraction from aqueous sulfuric acid solutions. Thus the extraction of... 

The alkyl phosphoric acids were first recognized as excellent actinide extractants because dibutyl phosphoric acid existed as an impurity in TBP (8). They extract well from unsalted solutions and from systems such as sulfate in which TBP is ineffective. Organo-phosphorus acids are thus suitable for uranium hydr metallurgical applications where ore is leached with sulfuric acid. The Dapex process is an example in which bis(2-ethylhexyl) phosphoric acid (HDEHP) is used alone or in synergistic combination with neutral organophosphorus compounds for uranium and vanadium recovery (9,10). 

Figure 3. Distribution ratios of dibutyl phosphoric acid (HDBP), monobutyl phosphoric acid (H2MBP), phosphoric acid (HsPOk), dodecyl sulfuric acid (DSA), and diethylenetriaminetetraacetic acid (H5DTPA) vs. aqueous HN03 concentration organic phase = 2-ethyl-l-hexanol T = 25° and 50°C.

Hydrolysis of TBP. Hydrolysis of TBP occurs stepwise via dibutyl and monobutyl phosphoric acid ([C4H9O] jPOjH and C4H9OPO3H2) and leads eventually to phosphoric acid. Dibutyl phosphoric acid is the most abundant degradation product. Its rate of formation is influenced by temperature, the nitric acid concentration, the uranium content, and the presence of a diluent, beside the radiation dose. The acidic nature of these hydrolysis products allows in principle cleanup by an alkaline wash. 

The effect of TBP degradation products, particularly of dibutyl phosphoric acid, is the formation of strong complexes with uranium(VI), plutonium(IV), zirconium, and niobium. The sequence of complexing strength is Zr > Pu(IV) > U(VI) > Nb. 

DIBUTYL PHOSPHORIC ACID (107-66-4) Reacts with moisture in air, forming hydrogen phosphate. Reacts with water, steam, forming phosphoric acid. Reacts violently with antimony(V) pentafluoride. Incompatible with lead diacetate, magnesium, nitrates, silver nitrate. Incompatible with strong oxidizers. Aqueous solution incompatible with sulfuric acid, alkalis, ammonia, aliphatic amines, alkanolamines, alkylene oxides, amides, epichlorohydrin, organic anhydrides, isocyanates, vinyl acetate. Attacks some plastics, rubber, and coatings. 

Tc(fV), obtained by reduction of TcO with hydrazine in 0.5 to 3 M IINO3, was extracted with a solution of 15 vol% of dibutyl phosphoric acid. Distribution coefficients only between 2 and 3 were observed for 1-2 M HNO3. Somewhat higher coefficients (Dvc=8.5) could be achieved when rc(TV) was extracted with thcnoyltrifluoro-acelonc from aqueous solutions of pH 6.5 to 9. Under these conditions more than 90% of Tc(lV) was extracted in a single equilibration step [156]. Some systematic studies on the extraction of Tc(lV) with several complexing extractants have been reported ] 157]. 

SYNONYMS dibutyl acid o-phosphate, dibuytl hydrogen phosphate, dibutyl phosphoric acid, phosphoric acid dibutyl ester. 

Synonyms/Trade Names Dibutyl acid o-phosphate, Di-n-butyl hydrogen phosphate, Dibutyl phosphoric acid... 

On the other hand, Dyrssen and Liem (1960) report (table 7) greater variation in both distribution ratios [for americium and europium extraction by dibutyl phosphoric acid (HDBP)] and in separation factors as a function of diluent. The separation factors and distribution coefficients are correlated (more or less consistently) inversely with the distribution ratio of the extractant between the phases. In this system, the largest separation factors are observed in n-hexane, chloroform, and carbon tetrachloride. Diluents capable of direct coordination (i.e., those possessing potential oxygen-donor atoms) are correlated with reduced distribution ratios and separation factors. The observations of greater separation factors in non-complexing diluents suggest that more effective separation is observed when the inner-coordination sphere of the hydrophobic complex is not disturbed. 

DIBUTYL PHOSPHATE (c,H/)).(omPO Dibuiyl acid < phosphatCi Dini-buCyl hydrogen phosphate, Dibutyl phosphoric acid Strong oxidizers y 9 ... 

Zilberman, B. Y, Fedorov, Y. S., Shmidt, O. V. et al. 2009. Dibutyl phosphoric acid and its acid zirconium salt as an extractant for the separation of transplutonium elements and rare earths and for their partitioning. J. Radioanal. Nucl. Chem. 279 193-208. 

Dibutyl phosphoric acid, see D-00237 0,0-Dibutyl phosphorodithioate, D-00241 0,0-Dibutyl phosphorothioate, D-00242 0,0-Dibutylphosphorothioic acid, see... 

---