摘要
研究了盐酸介质中(DOSO)萃取Pt(Ⅱ)的动力学及萃合物结构,推测其萃取反应机理为:①在[HCl]<2mol/L的体系中,Pt(Ⅱ)的萃取反应速率趋于零;而Pd(Ⅱ)却是配位机理,其速率比较高。②在[HCl]>2mol/L的溶液中,(DOSO)均以(?)盐化—配位机理萃取Pt(Ⅱ)和Pd(Ⅱ)。其萃合物分别为:顺式—[PtL_2Cl_2]·[H(H_2O)L]Cl,反式—[PdL_2Cl_2][H(H_2O)L]Cl(其中L=DOSO)。反应机理的异同符合“重铂族比轻铂族具有更稳定的热力学性质、而动力学反应惰性更大的规律。
The kinetics of extracting Pt (Ⅱ) and the structure of extractive compound were studied by DOSO in HC1 medium. The mechanisms of extraction reaction were deduced as follows. (1) in the system of [HCl]<2 mol/L, the rate of extraction of Pt (I ) was hardly equal to zero, but that of Pd (Ⅱ) was very fast; (2) in the solution of [HCl]>2mol/L, both Pd(Ⅱ) and Pt (Ⅱ) were extracted by DOSO with two mechanisms of oxonium formation and sulfer-atom coordination. Their extractive compounds were cis[PtL_2C1_2]·[H(H_2O)L]Cl and trans-[Pd L_2Cl_2]·[H(H_2O)L]Cl(L= DOSO) respectively The difference of extraction mechanisms for Pt (Ⅱ) and Pd (Ⅱ) was in accordance with the rule suggested by us, that is 'thermodynamic stability and kinetic inertness of heavy platinum group metals (Os, Ir, and Pt) are higher than that of light platinum group metals (Ru, Rh, and Pd)'
出处
《贵金属》
CAS
CSCD
北大核心
1991年第2期1-10,共10页
Precious Metals
关键词
铂
萃取
亚砜
反应机理
Platinum
Extraction
Sulfoxide
Reaction mechanisms
