有机单硫代磷酸-三辛胺反协同萃取镉锌

Anti-Synergetic Extraction of Cadmium and Zinc with Organic Monothiophosphoric Acid-Trioctylamine

研究了二 (2 乙基己基 )单硫代磷酸 (D2EHMTPA) 三辛胺 (TOA)混合萃取剂萃取镉锌的机理。电导滴定、红外和核磁共振谱以及等摩尔系列法等实验表明 ,D2EHMTPA与TOA混合形成离子缔合体 ,其萃取镉锌为反协同萃取 ,萃合物为CdA2 ·BHA和ZnA2 。萃取机理如下 :M2 ++ (2 +m)BHA(o) =MA2 ·mBHA(o) + 2B(o) + 2H+ (M2 + =Zn2 + 时 ,m =0 ;M2 + =Cd2 + 时 ,m =1)。

The extraction of cadmium and zinc with di (2 ethylhexyl) monothiophosphoric acid(D2EHMTPA or MTPA) trioctylamine(TOA) in toluene was investigated. Conductance titration, infrared spectrum and nuclear magnetic resonance spectrum etc. confirmed that by mixing DZEH MTPA with TOA is formed an electrolyte of ionic pairs(BH +A -), its extraction for cadmium and zinc is of antisynergistic nature and the extracted complexes are CdA 2·BHA and ZnA 2. The mechanism is proved as follows: M 2+ +(2+ m )BHA (O) =MA 2· m BHA (O) +2B (O) +2H +;(M 2+ =Zn 2+ : m =0 ; M 2+ =Cd 2+ : m =1).