活性炭吸附Au(CN)_2~-和Ag(CN)_2~-时氧的作用研究

Au(CN)_(2~-)、Ag(CN)_(2~-)和Hg(CN)_2在活性炭(Norit R 2020)上的吸附对比研究指出:氧和含氧表面官能团在炭吸附Au(CN)_(2~-)和Ag(CN)_(2~-)的过程中起了一定作用,但对Hg(CN)_(2)的吸附过程不起作用。在950℃和10~(-5)C(?)(1.33×10~(-3)F)的真空度下,脱氧的活性炭对Au(CN)_(2~-)和Ag(CN)_(2~-)的吸附量与未脱氧的活性炭相比,降低50％。然而,如果在溶液中有氧存在时,脱氧炭吸附Au(CN)_(2~-)的容量与未脱氧炭的相等,还研究了有机溶剂的影响和这两种类型炭对Au(CN)_(2~-)吸附电位的变化。研究结果指出,活性炭具有离子交换树脂的特性,但是活性炭可由化学吸附氧把氰化物和络合氰化物氧化。因此提出了活性炭吸附Au(CN)_(2~-)和Ag(CN)_(2~-)的双机理,该机理认为络合氰化物通过与OH-的阴离子交换而吸附在炭上,继而由于Au(CN)_(2~-)或Ag(CN)_(2~-)的部分氧化分解而成为不溶的AuCN或AgCN。     

Au(CN)_2~-和Ag(CN)_2~-吸附在活性炭上时的电位研究

Au(CN)_2~-和Ag(CN)_2~-在活性炭上的吸附,与炭的电位大小有关。本文提出Au(CN)_2-、Ag(CN)_2-和CN-是通过离子交换机理和导致炭电位降低的氧化作用而吸附在炭上的。炭电位按照其对阴离子吸附的能力,以下列顺序递减:Au(CN)_2->Ag(CN)_2->CN>I->C1-。炭吸附阴离子时,伴随有OH-的释出,从而增高了溶液的pH值,降低了炭的电位。炭与含KAu(CN)_2、KAg(CN)_2或KCN溶液接触时的电位,比在相同pH值下它与氯化物溶液接触时的电位低得多。研究结果表明,在炭表面上氰离子被氧或可还原的宫能团(如苯醌)所氧化。     

碳吸附金(I)氰化物的XPS研究

研究表明金以Au(I)络合物形式从KAu(CN)_2溶液中被吸附到NoritR-2020活性炭上.这类络合物的特性随条件而变.同先前的观测一样,当从除氧的溶液中吸附KAu(CN)_2时,Au∶K=1∶1.在充氧溶液中,吸附的Au∶K之比值随负载增至31∶1.Au∶CN∶N化学配比的研究表明,金以KAu(CN)_2和AuCN的混合物被均匀地吸附在整个炭上面,     

氰化金和氰化银在活性炭上的吸附行为和特征

本文重点讨论Au(CN)_2~-和Ag(CN)_2~-在活性炭上吸附的行为和特征。 当矿浆中只有Au(CN)_2~-或Ag(CN)_2~-时,它们在活性炭上的吸附过程和特征相同;当矿浆中既有Au(CN)_2~-又有Ag(CN)_2~-时,它们的吸附过程和行为又不相同。 Ag(CN)_2~-对Au(CN)_2~-在活性炭上吸附的连续性没有影响,但对吸附容量有影响。无Ag(CN)_2~-时金在活性炭上的吸附容量为q=40.71C~(0.717),有Ag(CN)_2~-时(本文叙及条件),金在活性炭上的吸附容量为q=4.4368C~(0.4701)。 q——吸附平衡时金容量,mg/g.c; C——吸附平衡时液相金品位,mg/L。 受Au(CN)_2~-的影响,Ag(CN)_2`-在活性炭上的吸附行为变化很大,可由吸附变为解吸。因此,当Au(CN)_2~-和Ag(CN)_2~-存在于同一体系时,它们在活性炭上的吸附不能同时完成,金、银必须进行分段吸附才能获得满意的吸附效果。     

A-21S和201×7树脂吸附处理氰化提金废水研究

采用两步沉淀对某黄金冶炼厂含高铜、铁氰化提金废水进行降铜除铁预处理后,对滤液分别进行A-21S树脂和201×7树脂吸附对比试验。结果表明,A-21S树脂对废水中各离子的吸附率均高于201×7树脂,对金和锌络合离子的吸附率高达96%以上。A-21S树脂吸附过程中,Au(CN)2-对CNT-、Cu(CN)32-和Zn(CN)42-的分离系数SA/B平均值分别为56.69、25和0.051,选择性系数KA/B平均值分别为56.69、487.63和1.015。A-21S树脂吸附Au(CN)2-的选择性比CNT-和Cu(CN)32-强,而吸附Au(CN)2-和Zn(CN)42-的亲和力接近。体系中Zn(CN)42-的存在对A-21S吸附Au(CN)2-有竞争。     

酸性硫脲溶液中金银分离的研究 (Ⅳ)离子交换树脂法

从H_2SO_4—CS(NH_2)—H_2O体系中分离金银的离子交换树脂法,是又一个较好的分离方法.上海744苯乙烯型树脂,对〔Au(SCN_2H_4)~2Ⅰ~+和〔Ag(SCN_2H_4)_3〕~+有很好的吸附性能,其大孔结构特性,更适合对大型配离子团的吸附.论文给出了HCl—Br_2(水)溶液为金的洗提剂;HCl溶液为银的洗提剂.单因素和多因素正交试验研究给出了吸附富集和解吸分离的最优工艺条件.     

离子交换树脂在金湿法冶金中的应用

金矿石中铜的存在给矿冶工业带来许多新问题。由于氰化物可溶解矿石中的铜矿物及天然铜形成了 [Cu(CN) 3 ] 2 -配合离子 ,且铜的溶解速度比金快得多 ,使得氰化物的消耗大大增加。因此从经济和环保角度出发 ,氰化物的再生令人关注。 Versiane A.Leao等人研究了金属氰化配合物在不同化学结构的离子交换树脂上的吸附与解吸性能。用 Cu SO4· 5 H2 O、Ni SO4· 6H2 O和 K4Fe(CN) 6· 3 H2 O配制 p H=10 .5的溶液 ,加入氰化钠使Cu2 、Ni2 转化成 [Ni(CN) 4 ] 2 -及 [Cu(CN) 3 ] 2 -和 [Cu(CN) 4 ] 3 -。最终的氰化配合物溶液中 ,…     

用加改性剂的胺从氰化物溶液中溶剂萃取金的化学

本文论述了胺碱度的概念,并利用它来解释从碱性氰化物溶液中的选择性萃取金的机理。对于Au(CN)_2-的萃取来说,添加有机磷化合物(TBP、DBBP等),可使低级弱碱性胺类的表观碱度提高五个数量级。但对其它氰化物阴离子,如Cu(CN)_4~3-和Zn(CN)_4~2-则没有这样大的影响,根据斜率和红外光谱结果分析,阐述了这种选择性的机理、萃取反应的理论配比和所萃取的阴离子性质。     

从氰化液中萃取铜的机理研究

本文研究了氢氧化三烷基甲铵(转型的N_(163))—煤油体系从氰化液中萃取铜的机理。采用多种方法对萃合物的研究表明,铜以Cu(CN)_4~(8-)的形式被萃入有机相,萃合物的主要形式分别为Cu(CN)4·3(R_8CH_3N)和Cu(CN)_4·(ReCH_3N)_2(R_8CH_3N)。     

VB/CHCl3液膜体系中银离子的传输分离

采用内耦合大块液膜分离技术, 通过考察料液相pH值、料液相NaCN浓度、载体浓度以及解析相NaOH浓度对Ag(Ⅰ)传输的影响, 研究了以维多利亚蓝(VB)为流动载体的液膜中银的传输规律, 并建立了渗透系数与pH值、 NaCN浓度以及载体浓度等之间的关系方程.结果表明, Ag(Ⅰ)以VB+*Ag(CN)2-离子缔合物形式在液膜中传输, 最佳传输条件为 料液相中NaCN浓度为5.0×10-3 mol*L-1(pH=5.5), 解析相为0.05 mol*L-1 NaOH, 载体VB浓度为4.00×10-4 mol*L-1.Ni(Ⅱ), Co(Ⅱ), Zn(Ⅱ), Cu(Ⅱ), Pb(Ⅱ)及Cd(Ⅱ)离子对Ag(Ⅰ)传输无影响.     

China's Major Non-ferrous Metals Imports & Exports

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Zinc Production by Province in 2014

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80% of Chinese Firms Purchasing Overseas Mines Ended up in the Red

<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic     

Copper Processing Profit Dropped Sharply,Copper Consumption Will Face Impact in the Second Half of the Year

正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field,     

Central Geological Prospecting Fund Newly Added 16.47 Million Tonnes of Bauxite in 2013

正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF     

Manufacturers of Copper Tube for Central Air Conditioner Use Face Mounting Pressure in the Final Quarter of the Year

正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure     

Xinjiang Ranks No.1 in Production of Primary Aluminum in China

正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year,     

Shenhuo Coal Industry and Electricity Power Completed800,000 t/a Aluminum Project in Xinjiang

正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform.     

Guangdong Metal Transaction Center has Become the Second Largest Precious Metal Transaction Platform Nationwide

正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness.     

Seven Rare Earth Projects Involving Close to 3 Billion Yuan Investment Landed In the HighTech Zone

正On May 22,Baotou Rare Earth Industry Cooperation Consultation MeetingProject Agreement-signing Ceremony was held in Ningbo,nearly 40 enterprises from Ningbo,Guangdong,Hunan,and Shanxi participated in project consultation.After multi-lateral communication,agreements were signed for a total of 7 rare earth projects successfully.