Reviews of Metallurgical Technology to Recovery Platinum Group Metals from Secondary Resource in China

China is extremely poor in mineral resources of Platinum Group Metals (PGMs), productive output of PGMs from mineral resource is 2.5 tons per year. At the same time, China is the biggest PGMs consumption country in the world, the mineral resource of PGMs is critical shortage, it shows the importance of recycling the secondary resource of PGMs. Sino-Platinum Metals Resource (Yimen) Co., Ltd. is the leader in recycling of PGMs from secondary resource, and has made outstanding contributions to China PGMs secondary resources recycling. This article elucidates the current situation of secondary resources recovery and development of metallurgical technology for PGMs.

Functions of Rare Earth Metals in Automobile Emission Purification Catalysts

The functions of rare earth metals in the automobile emission purification catalysts were reviewed, and it was clarified that with precious metals resources using up gradually emission regulations becoming more and more strict, rare earth metals will play more and more important roles in the high performance, and in low price automobile emission purification catalysts, they can not be substituted by other elements, for example, precious metals.

Synthesis,crystal structure and photo-physical properties of tris(4-methyl-2,5-diphenylpyridine)iridium for OLED

Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent materials.In this paper,Ir(bmppy)_(3),tris(4-methyl-2,5-diphenylpyridine)iridium,was synthesized and elvaluted for photo-physical characteristics.Single crystals suitale for X-ray diffraction(XRD)were grown from a mixture solvent of dichloromethane and absolute ethanol.The composition and structur of Ir(bmppy)_(3)were determined by element analysis,NMR spectra and XRD.The complex crystallizes in the monoclinic symmetry with the space group P21/c with a slightly distorted octahedral configuration.As measured by UV-Visible and photoluminescence spectra,Ir(bmppy)_(3) displays a maximum emission at at 527 nm at ambient temperature,a typical green-emitting profile.The complex has potential for application in the OLED industry.

Facile electrochemical surface-alloying and etching of Au wires to enable high-performance substrates for surface enhanced Raman scattering

Surface-enhanced Raman Spectroscopy(SERS)is a nondestructive technique for rapid detection of analytes even at the single-molecule level.However,highly sensitive and reliable SERS substrates are mostly fabricated with complex nanofabrication techniques,greatly restricting their practical applications.A convenient electrochemical method for transforming the surface of commercial gold wires/foils into silver-alloyed nanostructures is demonstrated in this report.Au substrates are treated with repetitive anodic and cathodic bias in an electrolyte of thiourea,in a one-pot one-step manner.X-rays absorption fine structure(XAFS)spectroscopy confirms that the AuAg alloy is induced at the surface.The unique AuAg alloyed surface nanostructures are particularly advantageous when served as SERS substrates,enabling a remarkably sensitive detection of Rhodamine B(a detection limit of 10^(-14)M,and uniform strong response throughout the substrates at 10^(-12)M).

Study on the Recovery of Rhodium from Spent Organic Rhodium Catalysts of Acetic Acid Industry Using Pyrometallurgical Process

A new process recycling rhodium from organic waste containing rhodium in acetic acid industry is developed. Use the special affinity of base metal sulfides (FeS, Ni2S3 , CuS, etc.) on platinum group metals, adopting high nickel matte trapping-aluminothermic activation method to recovery rhodium from incinerator residue of organic rhodium waste. The method is shorter process, lower equipment requirement, and the higher activity of rhodium black. In pyrometallurgy enrichment process,the recovery rate of rhodium reached 94.65%, the full flow of rhodium recovery rate was 92.04%.

Determination of Residues and Safety Analysis of Metal Impurities in Platinum-based Antitumor Drugs

The residual metal impurities in cisplatin, carboplatin and oxaliplatin were determined by ICP-AES. The samples were ignited and dissolved with HCl:HNO 3 (3:1). The method is simple and accurate. By the determination of the metal residues in the samples, the calculated actual daily exposure and concentration of the metal Pd, Ir, Rh, Ru, Mo, Ni, Cr, V, Cu, Mn, Fe and Zn that were less than the permitted daily exposures (PDE) and the limited concentration permitted in the EMEA guideline on the specification limits for residues of metal catalysts or metal reagents [1] . The metal residues can de adequately removed from the active pharmaceutical ingredients and the corresponding drugs. The trace metal residues will not affect human health and lead to the safety hazard by the intravenous injection.

A Review on Metal-support Interaction in Automotive Catalysts

TWC-equipped exhausts are widely used in gasoline-fueled vehicles to meet stringent emission regulations. The main components in TWCs are precious metals such as palladium (Pd), platinum (Pt), and rhodium (Rh) as the active component, and inorganic oxides such as γ-alumina (Al 2 O 3 ), ceria (CeO 2 ), zirconia (ZrO 2 ) and ceria-zirconia (CeO 2-ZrO 2 ) are used as the support. Interaction of precious metals and support plays an important role in the thermal stability and catalytic performance of TWCs. The support can improve the dispersion of precious metals and suppress the sintering of precious metals at high temperature. In the same, precious metals can also enhance the redox performance and oxygen storage capacity of support. This paper reviews the reaction phenomenon and mechanism of precious metals (Pt, Pd, Rh) and supports such as Al 2 O 3 , CeO 2-based composite oxides.

A new popular transition metal-based catalyst:SmMn_(2)O_(5) mullite-type oxide

Catalyst with high performance has drawn increasing attention recently due to its significant advantages in chemical reactions such as speeding up the reaction,lowering the reaction temperature or pressure,and proceeding without itself being consumed.Despite the superior catalytic performance of precious metal catalysts,transition metal oxides offer a promising route for substitution of precious metals in catalysis arising from their low cost,intrinsic activity and sufficient stability.Mullite-type oxide SmMn_(2)O_(5) exhibits a unique crystal structure containing double crystalline fields,and nowadays is used widely as the catalyst in different chemical reactions,including the reactions of vehicle emissions reduction and oxygen evolution reaction,gas sensors,and metal-air batteries,promoting attention in catalytic perfor-mance enhancement.To our knowledge,there is no review article covering the comprehensive informa-tion of SmMn2 O 5 and its applications.Here we review the recent progress in understanding of the crys-tal structure of SmMn_(2)O_(5) and its basic physical properties.We then summarize the catalytic sources of SmMn_(2)O_(5) and reaction mechanisms,while the strategies to improve catalytic performance of SmMn_(2)O_(5) are further presented.Finally,we provide a perspective on how to make further progress in catalytic applications.

铟回收过程中加铅富集铟工艺及Pb-In-Zn间相互作用分析

炼锌副产物是铟的主要来源之一,但在铟回收的过程中,铟易随水淬渣、含铜生铁流失,从而导致铟的回收率降低、损失增大。针对这些问题,本文提出了在锌还原熔炼回收铟的过程中加入铅富集铟从而提高铟回收率的新方法,并通过计算与实验证实了该方法的可行性。首先,基于密度泛函理论,对Pb-In-Zn团簇及熔体结构进行从头算分子动力学模拟,并通过计算其径向分布函数与扩散系数,对加铅富集铟的可行性进行分析。计算结果表明,经过动力学模拟后,In与Pb发生了明显的聚集,Pb-In间的相互作用明显大于Pb-Zn和Zn-In,且在Pb与In物质量比为3:1时Pb对In的富集效果最明显。随后依据理论结果开展Pb-In-Zn混熔实验,结果表明铅的加入明显提升了铟的回收率,且在Pb与In物质量比为3:1时铟的回收率最好,证实了计算结果的正确性。本研究为提升铟的回收率提供了切实可行的办法,为有色金属回收利用提供了新思路。

Study on the Leaching of Pt, Pd and Rh from Spent Auto-catalysts in Various Acidities

Auto-catalysts were the largest consumers of platinum group metals and the most important secondary resources, recovery of PGMs from spent auto-catalysts by leaching with various acidities were investigated. The leaching thermodynamics of PGMs at 363 K was first discussed. At 363 K the higher the acidities of HCl, the higher the leaching recoveries of PGMs, and the sequence of leaching recovery was Pd>Pt>Rh. When H2SO4 used alone, the leaching recoveries of PGMs was low, when the acidity of H2SO4 increasing, the leaching recovery of Rh kept stable.

Thermal Stability and Reductive Property of Ce_xZr_(1-x)O_2 Solid Solution Doped Simultaneously by Fe, Mn or Fe, Cu

CexZr1-xO2 complex oxides doped by transition metal(Fe, Mn, Cu) were prepared by precipitation method. Thermal stability of samples was characterized by XRD, surface areas were measured by BET method and reductive property was characterized by TPR. The results show that MnO2 can be dispersed in solid solution after calcined at 1273 K, when the loading is 12%, while Fe and Cu is easy to separate from samples at this temperature. Samples doped simultaneously by Fe, Mn or Fe, Cu demonstrated high reactive property at low temperature. The starting reduction temperature are 413 and 373 K, respectively. TPR results also show a broad range of reductive temperature exists in these bi-metal doped samples.

Influence of Al_2O_3/CeZrAl composition on the catalytic behavior of Pd/Rh catalyst

Al2O3 and Ce-Zr mixed oxides are important components of the automobile three-way catalyst.Various contents modifying A12O3(GAL) was physically introduced into Ce-Zr-Al mixed oxides(CZA) to form series of GAL/CZA composition.The Pd/Rh catalyst samples were prepared by different GAL/CZA support loading Pd/Rh,then aged at 950 oC for 6 h.The catalytic behavior of different Pd/Rh catalyst samples was studied.Surface area,oxygen storage capacity(OSC) and H2 adsorption capacity(TPR) of fresh and aged samples were...

Factors Research on the Influence of Leaching Rate of Nickel and Cobalt from Waste Superalloys with Sulfuric Acid

Unlike the reported leaching technologies of waste superalloys, the process of the “atomized spray-sulfuric acid leaching nickel and cobalt” technology was put forward in the present work according to the compositions of waste superalloys. The effects of sulfuric acid temperature, concentration, leaching time, stirring speed and size of superalloys on leaching of Ni and Co from waste superalloys have been mainly investigated, and the optimum leaching conditions were determined and reported. The leaching rates for nickel and cobalt were 96.68% and 96.63%, respectively, and the contents of nickel and cobalt in leaching slag were 6.77% and 0.96%, respectively. The obtained leaching solution containing Ni and Co could be used for production of Ni and Co products after removal.

The Status Quo and Development Trend of High-purity Gold Sputtering Targets

This article gives a brief introduction to manufacturers and markets of sputtering targets as well as the manufacturing technology thereof. Then, it analyzes the application of high-purity gold sputtering targets in the fields of integrated circuit, information storage, flat panel display, etc. Based on the above, the article analyzes the processing development trend for the high-purity gold sputtering targets in aspects of ultra-high purity, manufacturing technology, analysis and testing technologies.

Study of the Material Transfer Characteristics and Surface Morphology Due to Arc Erosion of PtIr Contact Materials

By means of breaking tests on PtIr contact materials via a JF04C contact material testing machine, it was attempted to elucidate the characteristics of the various surface morphology and material transfer after the arc erosion process caused by break arc. The material transfer characteristics appeared in the experiments were concluded and analyzed. Meanwhile, the morphology of the anode and cathode surface were observed and analyzed by SEM.

Influences of (Ce-Zr-La-Pr)O Contents on Three-Way Catalyst Performances

A series of catalysts with (Ce-Zr-La-Pr)O contents range from 0 to 50% in coating and single-palladium loads on substrates were prepared to study effects of (Ce-Zr-La-Pr)O contents on catalytic activities and durability by contrasting the characteristics of light-off, A/F and catalytic conversions of the fresh catalysts with that of the aged catalysts. The results show that (Ce-Zr-La-Pr)O can enhance the catalysts light-off characteristics, widen A/F windows and increase catalytic conversions at a certain extent through optimizing physical structural and chemical property of the mixed coating. However, (Ce-Zr-La-Pr)O contents influence greatly on the catalysts activities and durability, and the catalysts with contents ranging from 10% to 30% exhibited better integrative properties in all samples, and 10% was the optical content to make the catalyst performance highest in this thesis. It is indicated that an suitable content of (Ce-Zr-La-Pr)O plays an important role in assisting catalysis, enhancing durability and increasing oxygen storage capability.

Preparation of Lead-free Thick-film Resistor Pastes

The preparation of lead-free thick-film resistors are reported:using RuO 2 and ruthenates as conductive particles,glass powders composed of B 2 O 3,SiO 2,CaO and Al2 O 3 as insulating phase,adding organic matter which mainly consists of ethyl cellulose and terpineol to form printable pastes.Resistors were fabricated and sintered by conventional screen-printing on 96%Al 2 O 3 substrates,and then sintering in a belt furnace.X-ray diffraction(XRD) and electron scanning microscopy(SEM) have been used to characterize the conductive particles.The resistors exhibit good refiring stability and low temperature coefficient of resistance.Sheet resistance spans from about 80Ω/□ to 600Ω/□.The resistors prepared are qualified for common use.

Study on Catalysts with Rhodium Loading on Different Cerium-Zirconium Mixed Oxides

The catalysts with Rh loading on different cerium-zirconium mixed oxides were characterized by BET, H2-TPR and OSC. The effects of different cerium-zirconium mixed oxides on catalytic performance and thermal stability of Rh loaded catalyst were studied. The results show that: (1) Rh can enhance cerium-zirconium mixed oxides OSC and catalytic reaction rates; (2) cerium-zirconium mixed oxides with high Ce contents and low Zr contents are more favorable to the stability of catalysts. Moreover, the contents of CeO2 have important effect on catalysts characteristics, and the addition of some rare earth components, such as La, Pr and Nd also have some influences.

Influence of Trace Oxygen on the Mechanical Properties of High Pure Silver during Natural Aging

Two kinds of high pure silver materials with 5.3 ppm oxygen and 32.7 ppm oxygen were prepared by various melting processes, both samples were subjected to accumulative rolling with 95% thickness reduction. Their mechanical properties were tested during long natural aging. Results showed that the Ag sheet with 5.3 ppm oxygen is at full annealed state when natural aging 58 days or kept at 150℃ for 30 minutes, and the Ag sheet with 32.7 ppm oxygen is a little of recovery when natural aging a year. It is suggested that appropriate oxygen interstitial solute in Ag solid solution and a few of Ag2O particles at Ag grain boundaries impede the recovery and recrystallization of Ag sheets.

Studies on Determination of Ge in Au Alloys by Potassium Iodate Potentiometric Titration Method

The paper presents a new method of determining Ge in gold alloys by potassium iodate potentiometric titration rather than by traditional distillation separation. The influences of conditions such as the reduction acidity, dosage of sodium hypophosphite and reduction time on the determination of Ge were studied. Comparison was made between the influences of end-point indication for potential method and starch method on accruracy and precision of the analysed results, stability and sensitivity of end-point, selectivity of method and so on. The possibility of reaction in an electrochemical way was discussed. Ge in the alloys such as AuGe 12 , AuGeNi 12 2 , AuAgGe 18.8 12.5 and AuAgGeNi 43.8 6 0.2 was measured, respectively, with the relative standard deviation of 0.10%~0.31% and the recoveries of added standard Ge in sample of 99.40%～100.40% when the reduction acidity was 0.40~0.80 mol/L HCl and 3.3 mol/L H 3 PO 4, 15 g sodium hypophosphite and reduction time 40 min. The new method presented is high accuracy and precision in results, good stability and sensibility in end point, easy operation and strong selectivity of determination. When it is applied to analyse actual samples, satisfactory results are achieved.