HPMBP与N_(1923)协萃钯(Ⅱ)的机理研究

STUDY OF THE MECHANISM OF SYNERGISTIC EXTRACTION OF Pd(Ⅱ) WITH HPMBP AND N_(1923)

本文研究了 HPMBP 与 N_(1923)的氯仿溶液从硝酸介质中协同萃取钯(Ⅱ)的机理.用斜率法、等摩尔系列法确定协萃配合物的组成为 RNH_3Pd(PMBP)_3,反应式为:Pd_((a))^(2+)+3HPMBP_((o))+RNH_3NO_(3(o))RNH_3Pd(PMBP)_(3(o))+3H_((a))^++NO_(3(a))^-求得该协萃反应的平衡常数及协萃配合物的生成常数分别为:1gK_(12)=1.77,1gβ_(12)=2.63.

In this paper,the mechanism of synergistic extraction of pal- ladium(Ⅱ)from nitric acid solution with HPMBP(1-pheny1-3-methy1-4- benzoy1-pyrazole-5-one)and primary amine N_(1923)in CHCl_2 at 25±1℃ is studied.Results show that the synergistic effect is noticeable in this system,with the synergistic constant R equal to 53.43.The influence of concentration of HPMBP,N_(1923),NO_3^-and the values of pH on the distribution ratio D_(12)are investigated.The composition of the synergistic extraction complex is RNH_3Pd(PMBP)_3 as determined by the methods of slope and constant mole.The synergistic extraction reaction and addition reaction of palladium (Ⅱ)can be formulated as follows: Pd_((a))^(+2)+3HPMBP_((o))+RHN_3NO_(3(o))RNH_3Pd(PMBP)_3(0)+3h_((a))^++NO_(3(a)) Pd(PMBP)_(2(o))+ HPMBP_((o))+RNH_3NO_(3(o)) RNH_3Pd(PMBP)_(3(o))+H-((a))^++NO_(3(a))^- In addition,the equilibrium constants of synergistic extraction reaction and addition reaction of palladium(Ⅱ)at 25±℃ are calculated to be 1gK_(12)= 1.77,1gβ_(12)= 2.63.