丁基苯并噻唑亚砜萃取钯(II)的性能研究

用丁基苯并噻唑亚砜(用M表示)作萃取剂,在盐酸介质中对钯萃取性能进行研究,结果表明:以无臭煤油作稀释剂、M的浓度20%、盐酸浓度1.0mol/L、相比O/A=0.6、萃取时间10min时,钯的萃取率高于96.0%。浓度为60%的M对钯的萃取容量大于11g/L,说明M对钯萃取性能良好。在室温下,用8.0mol/LNH3.H2O可有效地反萃取钯,反萃取率可达到94.6%。

PMBP萃取钯的机理及热力学研究

本文研究了PMBP-CHCl_3从高氯酸介质中萃取钯的机理和热力学性质。在pH=0—2的酸度下,采用等摩尔系列法、饱和法及斜率法测得萃合物组成为Pd(PMBP)_2。通过紫外-可见光谱法证实了PMBP萃取钯属螯合机理,其萃取反应方程式为:Pd_(a)^(2+)+2HPMBP_(o)(?)Pd(PMBP)_2_(o)+2H_(a)

废旧钯萃取剂再生并同时回收铂族金属的研究

应用蒸馏法再生废旧钯萃取剂,不仅实现了钯萃取剂的再生,还能有效回收其中残留的铂族金属。主要考察了蒸馏温度、蒸馏时间对于废旧钯萃取剂萃取性能及其铂族金属回收率的影响。结果表明：蒸馏回收废旧钯萃取剂效果明显,具有高效、经济、环保的特点。蒸馏温度控制在135~140℃,蒸馏时间为8 h时,废旧钯萃取剂再生率为92.94%;对再生后萃取剂与新萃取剂进行红外光谱（IR）分析和萃取性能分析,结果表明：再生后的萃取剂性能稳定,主要官能团与新萃取剂完全一致;再生后的萃取剂总萃取率在99.92%~99.96%,而新萃取剂总萃取率在99.47%~99.90%,完全满足铂族金属萃取分离工艺的要求。通过经济分析,蒸馏1 L废旧钯萃取剂可节约成本600元,并且其中的铂族金属总回收率可达94.86%。

Extraction of Palladium (Ⅱ) with p-Methylphenylalkylsulfide from Aqueous Chloride Media

p-Methylphenylalkylsulfide of various alkyl chain length as extractant were synthesized and the extraction of palladium was examined in terms of equilibrium and kinetics. Distribution ratio of Pd was independent of alkyl chain length. For aqueous chloride media, there was a significant difference in distribution ratios for the solution of NaCl and HCl. The results of loading test and the slope analysis suggest that the extractant and Pd (Ⅱ) form 2:1 complex. Furthermore, the extraction rate based on the volume of aqueous phase was obtained in a stirred vessel, and the rate equation was presented. Unfortunately, it was difficult to construct surfactant liquid membrane system by use of the present extractant.