TY - GEN
T1 - Behavior of uranium(VI) during HEDPA leaching for aluminum dissolution in tank waste sludges
AU - Powell, Brian A.
AU - Rao, Linfeng
AU - Nash, Kenneth L.
AU - Martin, Leigh
PY - 2006
Y1 - 2006
N2 - Batch adsorption/dissolution experiments were conducted to examine the interactions between 233U(VI) and a synthetic aluminum oxyhydroxidc (boehmitc, γ-AlOOH) in 1.0M NaCl suspensions containing l-hydroxyethane-l,l-diphosphonic acid (HEDPA). In the pH range 4 to 9, complexation of Al(III) by HEDPA significantly enhanced dissolution of boehmite. This phenomenon was especially pronounced in the neutral pl-l region where the solubility of aluminum, in the absence of complexants, is limited by the formation of sparsely soluble aluminum hydroxides. At high pH levels, dissolution of synthetic hoehmitc was inhibited by HEDPA, likely due to sorption of A1(III)/HEDPA complexes. Addition of HEDPA to equilibrated U(VI)-synthetic boehmite suspensions yielded an increase in the aqueous phase uranium concentration. The concentration of uranium continually increased over 59 days. Partitioning of uranium between the solid and aqueous phase was found to correlate well with HEDPA partitioning.
AB - Batch adsorption/dissolution experiments were conducted to examine the interactions between 233U(VI) and a synthetic aluminum oxyhydroxidc (boehmitc, γ-AlOOH) in 1.0M NaCl suspensions containing l-hydroxyethane-l,l-diphosphonic acid (HEDPA). In the pH range 4 to 9, complexation of Al(III) by HEDPA significantly enhanced dissolution of boehmite. This phenomenon was especially pronounced in the neutral pl-l region where the solubility of aluminum, in the absence of complexants, is limited by the formation of sparsely soluble aluminum hydroxides. At high pH levels, dissolution of synthetic hoehmitc was inhibited by HEDPA, likely due to sorption of A1(III)/HEDPA complexes. Addition of HEDPA to equilibrated U(VI)-synthetic boehmite suspensions yielded an increase in the aqueous phase uranium concentration. The concentration of uranium continually increased over 59 days. Partitioning of uranium between the solid and aqueous phase was found to correlate well with HEDPA partitioning.
UR - http://www.scopus.com/inward/record.url?scp=33646402619&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:33646402619
SN - 1558998470
SN - 9781558998476
T3 - Materials Research Society Symposium Proceedings
SP - 337
EP - 342
BT - Materials Research Society Symposium Proceedings
T2 - 2005 Materials Research Society Fall Meeting
Y2 - 28 November 2005 through 1 December 2005
ER -