共搜索到32条信息,每页显示10条信息,共4页。用时:0小时0分0秒427毫秒
) phosphoric acid (HDEHP, HA) as extractant was investigated. The results indicated that the maximum synergistic enhancement coefficients were obtained at the mole fraction of HEH/EHP=0.6, and cerium(IV... such as △G, △H, and △S were determined in the extraction of Ce(IV) from sulfuric medium using mixture of HEH/EHP and HDEHP. Key words:synergistic extraction; cerium; HEH/EHP; HDEHP; sulfuric acid......
从混合酸性磷类负载有机相中反萃稀土的研究 龙志奇1,张永奇1,朱兆武1,张国成1,王春梅1,黄小卫1 (1.北京有色金属研究总院稀土材料国家工程研究中心,有研稀土新材料股份有限公司,北京,100088) 摘要:对负载Sm,Gd,Y的HDEHP和HEH/EHP混合萃取体系进行了反萃性能研究,测定了不同酸度下的累积反萃率,表明反萃率随混合体系中HEH/EHP摩尔比的增加而增大,对于Sm,Gd,Y来说,Sm在有机相中最易反萃,Y最难反萃.同时比较了相同酸度的HCl,HNO3及H2SO4对同一负载有机相的反萃性能,反萃能力为HCl>HNO3>H2SO4.采用HCl对负载Y的HDEHP和HEH/EHP及HDEHP和Cyanex272两种混合萃取体系的反萃性能进行了比较,表明后者具有更优异的反萃性能. 关键词:HDEHP; HEH/EHP; Cyanex272; 稀土; 反萃; [全文内......
酸性磷类萃取剂在硫酸介质中对Y(Ⅲ)的协萃机制研究 龙志奇1,张永奇1,张国成1,王春梅1,黄小卫1 (1.北京有色金属研究总院稀土材料国家工程研究中心,有研稀土新材料股份有限公司,北京,100088) 摘要:对HDEHP(H2A2),HEH/EHP(H2B2),Cyanex272(H2L2)萃取剂在硫酸介质中单独以及HDEHP-HEH/EHP和HDEHP-Cyanex272混合萃取剂萃取稀土元素Y(Ⅲ)的机制进行了研究. 研究发现,单独采用HDEHP和HEH/EHP萃取Y(Ⅲ)时,SO2-4参与了反应,造成反应过程中放出的H+个数随萃取剂浓度的变化而变化,对于单独采用Cyanex272萃取Y(Ⅲ)的过程中则是OH-参与了反应. 计算了混合萃取剂萃取Y(Ⅲ)的协萃系数(R),当水相平衡pH=1.2时,HDEHP和HEH/EHP混合萃取体系与HDEHP和Cyanex272混合萃取体系......
二(2-乙基己基)磷酸在锌电积过程中的行为沈湘黔,姚吉升,周忠华摘 要:用循环伏安法,X-光衍射,扫描电镜和X-射线能谱研究了HDEHP在锌电积过程中的行为.随电解液中HDEHP含量的增加,锌电积电流效率降低,活化超电位增大,晶面取向呈一定顺序(11.2)→(10.1)→(11.0).活化超电位与晶面取向之间存在一定的关系.当HDEHP<10mgl-1,不会产生有机烧板,电锌具有较大的六方片状晶.有机烧板由萃取剂HDEHP引起而不是由稀释剂煤油引起的.烧板物由锌和HDEHP组成.根据电极过程动力学和晶体成长理论解释了实验结果.关键词:......
叔碳酸类对稀土元素的萃取杨燕生,李沅英,邹东,梁远明中山大学广东有色金属研究院华南师范学院摘 要:<正> 稀土元素的溶剂萃取工艺,应用较早的是TBP体系,但是,它的分离效率不高.目前,国内外较多的采用HDEHP体系,用它进行稀土元素的萃取分组和个别稀土元素的萃取纯化,但是,它对重稀土的萃取分离较困难,且难于反萃取.近年来,国内外学者对羧关键词:......
)phosphoric acid(HDEHP)in kerosene.Equilibrium and kinetics studies for Ti(Ⅳ)were carried out in the presence of impurities that were leached with Ti(Ⅳ).Parameters affecting extraction rate of Ti(Ⅳ)from... of the experimental results suggests that TiO2+extraction rate by HDEHP is the first with respect to hydrogen ion concentration and HDEHP concentration.The results are interpreted by a reaction mechanism......
Extraction of Metal(Ti,V,Mo)-oxyl Cations by Monoacidic Phosphates and Phosphonates傅洵,傅有君,牛增元,胡正水,辛惠蓁,张雅萍摘 要:<正> The extraction of TiO2+,VO2+,VO2+ and MoO22+by HDEHP,HEHEHP and HDTMPP was studiedrespectively.The orders of extraction ability for the three extractant systems are as follows:for TiO2+,VO2+:HDEHP>HEHEHP>HDTMPP;for VO2+, MoO22......
, by mixtures of di-(2-ethylhexyl) phosphoric acid (HDEHP, H2A2(0)) and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (HEH/EHP, H2L2(0)) were studied. The distribution ratios and synergistic coefficients of Nd3+ and Sm3+ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm3+ or Nd3+. The chemical......
液膜法提取氯化钴李玉萍,王献科摘 要:用HDEHP[=( 2 -乙基己基 )磷酸 ]液膜体系对钴进行提取.该体系包括流动载体(HDEHP),表面活性剂 (L113B),膜增加剂 (液体石蜡 ),溶剂 (磺化煤油 )和内相 ( 2 .5mol/LHCl).研究了液膜的稳定性,温度,Co2 +浓度,HCl浓度,外相pH值,乳水比和油内比等因素对提取钴的影响.实验结果表明 ,在适当条件下 ,CoCl2 的提取率可达 91%以上.在此情况下 ,许多共存离子都不迁移,透过此液膜.只有Co2 +可以从这些离子中得到满意的分离.此法已用于提取黄铁矿,烟灰,炉渣和含有钴废催化剂中的钴 ,CoCl2 的纯度大于 99.5 %.关键词:钴;提取;液膜法;含有钴废催化剂;......
-(2-ethyl hexyl) phosphoric acid(HDEHP, HA) as extractant was investigated.The results indicated that the maximum synergistic enhancement coefficients were obtained at the mole fraction of HEH/EHP=0.6... and thermodynamic functions such as △G, △H, and △S were determined in the extraction of Ce(IV) from sulfuric medium using mixture of HEH/EHP and HDEHP关键词:......