(太原理工大學(xué) 化學(xué)化工學(xué)院,太原030024)
摘 要: 采用陰極電沉積方法制備電活性NiHCF薄膜,考察薄膜在含Pb2+溶液中的電控離子交換性能。在0.1 mol/L的Pb(NO3)2溶液中,通過(guò)循環(huán)伏安法調(diào)節(jié)膜電極的氧化還原電位考察其活性和可逆性,并結(jié)合電化學(xué)石英晶體微天平(EQCM)技術(shù)分析離子的交換機(jī)制,同時(shí)比較Co(NO3)2和Ni(NO3)2溶液中NiHCF膜電極的電化學(xué)行為;在0.1 mol/L [Pb(NO3)2+Co(NO3)2]和0.1 mol/L [Pb(NO3)2+Ni(NO3)2]兩組混合溶液中,通過(guò)循環(huán)伏安法分析薄膜對(duì)Pb2+/Co2+和Pb2+/Ni2+的選擇性;并通過(guò)X射線能譜儀(EDS)分別測(cè)定膜在氧化和還原狀態(tài)下的元素組成。結(jié)果表明,電活性NiHCF膜在含Pb2+、Co2+和Ni2+溶液中均具有可逆的離子交換行為,對(duì)Pb2+的選擇性高于對(duì)Co2+和Ni2+的,通過(guò)電控離子交換方法可以使Pb2+從廢水中得到有效分離。
關(guān)鍵字: NiHCF薄膜;鉛(II)分離;離子交換;電化學(xué)石英晶體微天平
thin films in aqueous solutions containing Pb2+
(College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, China)
Abstract:Electroactive nickel hexacyanoferrate (NiHCF) thin films were synthesized by cathodic deposition. The performance of electrochemically switched ion exchange (ESIX) of the NiHCF film for the separation of Pb2+ from aqueous solutions was investigated. In 0.1 mol/L Pb(NO3)2 solution, cyclic voltammetry (CV) combined with electrochemical quartz crystal microbalance (EQCM) technique was used to investigate the electroactive, reversibility of the film electrodes and the mechanism of ion exchange. The electrochemical behavior of NiHCF film electrodes was also compared with that in Co(NO3)2 and Ni(NO3)2 solutions. The ion selectivity of the film was investigated in 0.1 mol/L mixture solution containing [Pb(NO3)2+Co(NO3)2] and [Pb(NO3)2+Ni(NO3)2], respectively. The elementary composition of NiHCF films in reduced and oxidized form were also characterized by energy dispersive X-ray spectroscopy (EDS). The results show that the electroactive NiHCF films have reversible electrochemical behavior in aqueous solutions containing Pb2+, Co2+ and Ni2+, respectively. NiHCF film electrodes display a high Pb2+ selectivity in both Pb2+/Co2+ and Pb2+/Ni2+ binary mixtures and Pb2+ can be separated effectively from aqueous solutions by ESIX processes.
Key words: NiHCF film; Pb(Ⅱ) separation; ion exchange; electrochemical quartz crystal microbalance


