POLYORGS型螯合物吸附剂富集贵金属的新进展

叙述了ＰＯＬＹＯＲＧＳ型螯合吸附分离富集贵金属的新进展。对吸附剂的合成，性质及其对贵金属的吸附条件和实际应用作了简要介绍，这类吸附剂对贵金属吸容量大，选择性高，操作简单，方便，与勘察测定方法相结合，可获得测定贵金属的满意结果。     

贵金属吸附预富集的新进展

在查阅大量国内外文献的基础上,结合贵金属分离与富集的研究现状,综述了近年来有关贵金属吸附预富集方法的研究概况。重点论述了活性炭、螯合树脂、植物体及微生物四种常用吸附剂的应用现状及前景,通过比较四种吸附剂的优缺点为人们选择吸附剂提供了依据。最后结合个别生物吸附机理对新型微生物吸附剂进行详细的探讨,并展望了微生物吸附剂的发展前景。     

采用聚苯乙烯—偶氮 噻嗪烷—二砜[2.4]X射线荧光测定矿物中的金银

x射线光谱法已成功地应用于测定工业产品中的贵金属。其分析的准确度和再现性不亚于化学法。然而由于此方法的灵敏度低(Cnp Au=0.005％,Cnp Ag=0.01％)在微量分析时采用了各种预浓缩手段。 从方法的快速性和简便性来看,吸附法最引人注意。最近为了选择浓缩金和其它贵金属研制了大量的聚合螯和吸附剂,这些吸附剂能从大量的非贵金属元素中使微量的贵金属分离出来。螯合吸附剂浓缩     

从活性炭上解吸金和银的条件

为了有效地从活性炭上回收贵金属,就需要从吸附剂上完全分离已吸附的贵金属矿物组分,并使活性炭能恢复其原有的吸附容量。 参考文献中指出,使用过量的络合剂溶液能相当有效地从活性炭上回收已吸附的银。采用这一方法的前提是必须制定出对被活性炭从氰化溶液中吸附的金、银进行解吸的最佳制度。     

重组蛋白A免疫吸附剂的制备及吸附性能

以琼脂糖凝胶为载体,重组蛋白A为配基制备免疫吸附剂.过血浆动态吸附之后洗脱得到含有免疫球蛋白的洗脱液;通过分析洗脱液中免疫球蛋白的纯度可以考察吸附剂对免疫球蛋白的吸附选择性;最后利用等温静态吸附检测了吸附剂对人免疫球蛋白(hIgG)溶液的吸附行为.结果表明,洗脱液中免疫球蛋白的纯度大于92%,重组蛋白A吸附剂对免疫球蛋白吸附选择性较好;等温静态吸附结果符合Langmuir等温吸附模型;进一步分析Langmuir吸附模型,表明该吸附剂在临床治疗中有吸附量大的明显优势,重组蛋白A免疫吸附剂具有很好的临床应用前景.     

从难处理硫化物黑色页岩矿石中回收贵金属

<正>O.N.Kononovaa等研究了从难处理硫化物黑色页岩矿石及精矿中回收贵金属的方法,该矿石含金、银和铂族金属(钯和铂),取自俄罗斯苏霍依洛格金(Sukhoy Log)矿床。在常压、压力0.7MPa、温度为200℃的高压釜中浸出贵金属。结果表明,在有MnO2存在条件下,先用HCl/NaCl溶液对矿石进行氯化处理,然后用Purolite阴离子交换树脂和炭吸附剂Calgon GRC-22从浸出液中吸附贵金属,浸出     

贵金属的新型螯合吸附剂

本文叙述了富集贵金属的新型螯合吸附剂“POLYORGS”的性质。POLYORGS是由不同的聚合物(聚苯乙烯、苯乙烯与二乙烯苯的共聚物、纤维性物质)制成的,它们含有杂环胺和偕胺肟基团并对贵金属有选择性。本文介绍了贵金属先用POLYORGS吸附剂富集,然后,进行测定的几种方法。     

用活性炭从氰化矿浆中吸附回收贵金属

用离子交换剂从矿浆中回收金属的吸附工艺的发展和高强度的炭吸附剂制取工艺的研究,促进了用活性炭从氰化矿浆中回收金银的研究工作.苏联和其他国家所做的研究及外国企业的生产实践证明,采用炭吸附剂从溶液和矿浆中回收贵金属可获得明显的经济效果.其原因是活性炭比阴离子交换剂便宜80～     

富集分离贵金属的新螯合吸附剂—Полиоргс Ⅴ和Ⅵ

由于不同的螯合吸附剂含有不同的分析功能团,这些功能团可选择性的与金属离子进行成络反应,从而使螯合吸附剂富集分离金属离子时具有很高的选择性.所以,螯合吸附剂近年来已广泛的在分析化学上用来浓缩、富集极稀溶液中的微量元素和分离浓盐溶液中的某些低含量元素.有关螯合吸附剂的进展应用情况已有许多出色的述评,在贵金属的富集分离方面也有综述报导.本文仅就最近出现的富集分离贵金属的新螯合吸附剂作一简介.     

SDBS改性桑杆吸附剂对Cd~(2+)的吸附机制试验研究

研究了采用十二烷基苯磺酸钠(SDBS)对桑杆吸附剂进行改性,考察了改性桑杆吸附剂对Cd~(2+)的吸附动力学及吸附等温线,表征了改性前后、吸附前后桑杆吸附剂表面官能团的结构。结果表明:1)用SDBS改性后的桑杆吸附剂中多个官能团的特征吸收峰明显变强,表明SDBS已结合在桑杆吸附剂上,改性有效;改性吸附剂吸附Cd~(2+)后,羟基和C—O官能团的吸收峰变强变宽,表明桑杆表面的这些官能团是Cd~(2+)吸附反应的结合点位。2)改性桑杆吸附剂对水溶液中Cd~(2+)的吸附容量较大,在吸附时间3 h、吸附温度50℃、溶液中Cd~(2+)初始质量浓度25 mg/L、溶液pH=7、吸附剂用量7.5 g/L条件下,Cd~(2+)吸附率可达96.8%以上。3)改性桑杆吸附剂对Cd~(2+)的吸附过程可用准二级动力学吸附模型加以描述,吸附过程符合Freunndlich等温吸附模型,吸附易于进行。     

Reductive-Sorption Methods for Noble Metals Extraction from Solutions

Active carbons combining the properties of ion exchangers and reductive sorbents, take a special place among sorption materials for noble metal extraction from solution. Electrochemical mechanism is the specific feature of the noble metals sorption by active carbons. In the present work on the natural phenomena of reductive sorption of electropositive metals (Cu sub-group, platinoids) using synthetic active carbons of SCN or SCS type are studied. Synthetic carbons have been indicated to extract electropositive metal ions both from concentrated and diluted media (solutions of hydrometallurgy conversion, sewage and rinse flushes of galvanic production, etc.)

Synthetic carbons were shown to have high selectivity in extracting gold and silver from alkaline cyanide solutions of gold-containing raw material processing. Synthetic carbons of SCN type make it possible to extract palladium and platinum from hydrochloric acid solutions up to the overflow decantation level 100-fold against the background. Using the technique of internal electrolysis (systems: Carbon/Zn, Carbon/Al) gives the possibility, with reductive sorption method, to select rhodium and ruthenium from solutions of complex salt composition with the formation of metallizing carbon granules.

It was indicated that the selectivity and high extraction of these metals from fluid media are connected with the possibility of using sorption to reduce ions to metallic phase formation. Carbons coated by noble metals or metal complexes can be used as a catalyst. The proposed approach (reductive sorption) and applied new materials (synthetic carbon) give the possibility to solve important tasks of noble metal hydrometallurgy, environmental protection, and catalyst production.     

贵金属分析的新试剂—罗丹宁双偶氮化合物

本文介绍了三种贵金属分析的新试剂,它们是苯基偶氮苯偶氮罗丹宁、磺基酚偶氮苯偶氮罗丹宁、磺基苯偶氮苯酚偶氮罗丹宁。文中对三种新试剂的合成、性质、与贵金属反应的情况进行了叙述。     

四川有色金属工业"十五"发展成就回眸

文章介绍了四川有色金属工业的整体概况,通过对2000年至2005年全省有色行业生产经营及发展情况的总结及横向纵向比较分析,将四川有色行业十五发展成就归纳概括为：“生产总量翻番,行业地位上攀,新建企业突起,特色优势显现。技术进步加速,发展后劲十足。”同时还指出了四川有色金属工业存在的问题和不足。     

Palladium and platinum recovery from bicomponent mixtures using chitosan derivatives

Chitosan has been used as a base material for the preparation of platinum and palladium sorbents. Chitosan derivatives were obtained by glutaraldehyde cross-linking (GA), by poly(ethyleneimine) grafting (PEI), and by thiourea grafting (TDC). These sorbents were tested for the recovery of platinum group metals (PGMs) in batch systems and column systems from bicomponent mixtures at the optimum pH (ca. pH 2). Sorption isotherms were determined in batch systems, considering the impact of the excess of one metal on the sorption of the second. The sorbents have a marked preference for palladium over platinum. In most cases, the total sorption capacity (taking into account both Pd and Pt sorption) was comparable to that of each metal individually, indicating that the metals compete for the same sorption sites, regardless of the type of sorbent. In fixed-bed systems, similar effects were observed, with typical profiles driven by the displacement of platinum by palladium, attributed to the greater affinity of the sorbents for palladium. The sorbents (especially GA and TDC) have a greater selectivity for Pd than for Pt, compared to PEI, which has greater sorption capacities. Metal desorption was tested using several eluants, none of which allowed the complete removal of the metals from loaded sorbent, nor the selective desorption of either. A complete separation of the metals was not obtained, but by combination of sorption and desorption conditions, a concentration of Pd of 10- to 20-fold was achieved.     

Control of Chromated Copper Arsenate Wood Incineration Air Emissions and Ash Leaching Using Sorbent Technology

Chromated copper arsenate (CCA) has been the predominant wood preservative used in North America in recent years. The emission of volatile metals and leaching from the combustion ash of CCA-treated wood pose serious concerns. In this work, mineral sorbents were evaluated for their capabilities to control both problems. Results of thermodynamic analyses suggested that alkali and alkaline earth metal-based sorbents can potentially react with the metals during combustion. Experiments were conducted by mixing and burning mineral sorbents including lime and soda ash with CCA-treated wood in a fixed bed. Calcium-based sorbents showed great increase in the retention of arsenic (from 60 to 85%) and chromium (from 55 to 80%) and reduction in the leaching of arsenic (from 200 down to 0.1 mg/L) and copper (from 100 down to 1 mg/L). Sodium-based sorbents successfully retained metals in the ash below 750°C, but the products were highly leachable (over 1000 mg/L). The speciation of the products plays a critical role in determining the fate of the metals.     

Extraction of noble metals with macrocyclic compounds III: Extraction with calyxarenes

The third and final part of a review on the extraction of noble metals by macrocyclic compounds, which is devoted to extraction with O-, S-, and N-containing calyxarenes with a generalization of References from 1978 to 2008, is presented. it is noted that no systematic investigations on the extraction of noble metals with calixarenes has been performed until now. most works are qualitative and do not consider the regularities of the influence of the compositions of aqueous and organic phases and the properties of the extractant on the degree of metal extraction. the studied solutions are unlike production ones in regards to composition, and the chemical state of extracted ions in aqueous solutions is not always taken into account. it is emphasized that there is only fragmentary information on reextraction in the literature. the problem of the selectivity of extraction of noble metals with calixarene esters is discussed.     

Pyrazole-containing polymer sorbents for recovery of gold and silver from cyanic solutions

The results of an investigation into imparting hydrophilic properties to pyrazole-containing sorbents in cyanic media and increasing their capacitive characteristics with respect to noble metals are presented. It is established that adding up to 30% (relative to 3(5)-methylpyrazole) of triethanolamine or trimethylamine into the resin matrix exerts a positive effect on the capacitive characteristics of sorbents based on styrene divinylbenzene and 3(5)-methylpyrazole. It is shown that the introduction of deprotonating additives into the reaction mixture when synthesizing a sorbent of SDP-d grade makes it possible to increase its sorption capacity by 20–25% in regards to silver for its recovery from the AgNO₃ solution (the number of functional groups of resin correspondingly increases). A sorbent of SDDP-d grade of microporous structure with an increased content of 3(5)-methylpyrazole groups is obtained. The synthesized samples of resins are compared in regards to sorption from cyanic solutions on the background of high Cu and Zn contents in starting solutions. The sorption isotherms of Au, Ag, Cu, and Zn on the SDDP-d resin from cyanic solutions are recorded, and the sorption ability series Au > Ag > Zn > Cu is determined.     

Dynamic Adsorption of Heavy Metals under Various Incineration Temperatures

Previous studies have indicated that an effective control technology, for heavy metal emissions from incinerators, is to use solid sorbents to capture metals by physical deposition and chemical adsorption. The controlling efficiency is affected by the kind and size of sorbents, the operating temperature, and the specific compositions of the waste. However, the dynamic adsorption behavior of heavy metals on sorbents during incineration is rarely discussed, because it is difficult to analyze and identify trace metals at high temperatures. The main objective of this study is to investigate the dynamic adsorption behavior of Cr, Cu, Pb, and Cd on sorbents (silica sand with limestone) at different operating temperatures (600, 700, and 800°C) and to find the adsorption saturation point of the sorbents during fluidized bed incineration. This will help us to determine when the sorbents should be renewed and investigate the adsorption mechanism. The results show that the adsorption saturation points of three of the four metals were: (1) Cr, 1.4 mg∕g at 600°C, 1.04 mg∕g at 800°C; (2) Pb, 16.08 mg∕g at 600°C, 12 mg∕g at 800°C; and (3) Cu, 10.6 mg∕g at 600°C, 5.34 mg∕g at 700°C. The adsorption capacity follows the sequence of Pb > Cu > Cr > Cd.     

Methods of Minerals Modification by the Micro- and Nanoparticles of Gold and Platinum for the Evaluation of the Collectors Selectivity at the Flotation Processing of Noble Metals From the Fine Ingrained Ores

The paper explicates methods of the mineral surface coating by noble metals allowing to obtain samples with micro- and nanoparticles of Au and Pt, simulating natural objects. The purpose is to investigate the sorption and flotation properties of collectors. As a result we obtained the samples of pyrite, pyrrhotine, arsenopyrite, and quartz artificially enriched by micro-sized and nano-sized particles of noble metals. The coating of noble metals was carried out using the method of reducing adsorption from H₂[PtCl₆], H[AuCl₄], Na₂[PtCl₆], and Na[AuCl₄] solutions and the method of adsorption of nano-sized particles from Au and Pt sols. Depending on the conditions of the sulfides enrichment by noble metals and sizes of new formations of Au and Pt, we considered possible areas of application, methods of samples’ research, and reagents interaction with microparticles and nanoparticles of gold and platinum. A complex of research methods of reagents’ interaction with metals and flotation investigations of minerals and ores revealed the selective properties of new complexing collectors (perhydro-1,3,5-ditiazin-5-yl-methane (MTKH), sodium di(isobutyl)dithiophosphinate (DIF), 2-(ethylthio)ethylamine (ETEA)) due to their chemical interaction with gold and platinum.     

The extraction of noble metals by macrocyclic compounds

This is analytical article devoted to the extraction of noble metals by acyclic analogs of crown ethers (podands) covering the period from 1980 to 2007. Most attention is given to the extraction of noble metals by phosphoryl-containing podands from hydrochloric acid solutions. The efficiency of extraction depends mostly on the number and nature of donor centers in a reagent molecule. It is shown that the use of podands as noble metal extractants does not help to solve the problem of selective separation of noble metals from complex solutions.