| Name | Palladium |
| Synonyms | Palladium PALLADIUM SILVER ALLOY POWDER -2.5 MICRON SPHERICAL |
| CAS | 7740-05-3 |
| EINECS | 231-115-6 |
| InChIKey | KDLHZDBZIXYQEI-UHFFFAOYSA-N |
| Molecular Formula | Pd |
| Molar Mass | 106.42 |
| Density | 1.025 g/mL at 25 °C |
| Melting Point | 1554 °C(lit.) |
| Boling Point | 2970 °C(lit.) |
| Water Solubility | INSOLUBLE |
| Appearance | Form wire, color Silver-gray |
| Storage Condition | no restrictions. |
| Stability | Stable. Flammable - fine powder may cause fire or explosion in air. Incompatible with ozone, sodium tetrahydroborate, sulphur, arsenic. |
| Physical and Chemical Properties | The chemical properties are silver-white metal (face-centered cubic crystal). Soluble in aqua regia, hot nitric acid, sulfuric acid, slightly soluble in hydrochloric acid, insoluble in cold water and hot water. |
| Use | Uses are mainly used for thick film slurry in the electronic industry, internal and external electrode materials for multilayer ceramic capacitors; used for making catalysts, and also used for making dental materials, watches and surgical appliances; used for making catalysts (palladium asbestos, sponge palladium, etc.), Low current contact points, printed circuits, alloys for clocks, etc.; used for electrical instruments, precision alloys, etc.; electrical instruments, chemical industries and manufacturing precision alloys. |
| Risk Codes | R61 - May cause harm to the unborn child R33 - Danger of cumulative effects R37/38 - Irritating to respiratory system and skin. R40 - Limited evidence of a carcinogenic effect R41 - Risk of serious damage to eyes R36/37/38 - Irritating to eyes, respiratory system and skin. R11 - Highly Flammable |
| Safety Description | S53 - Avoid exposure - obtain special instructions before use. S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S24/25 - Avoid contact with skin and eyes. S36 - Wear suitable protective clothing. S22 - Do not breathe dust. |
| UN IDs | UN 3089 4.1/PG 2 |
| WGK Germany | - |
| RTECS | RT3480500 |
| TSCA | Yes |
| HS Code | 28439000 |
| Hazard Class | 4.1 |
| Packing Group | III |
| Toxicity | LD50 oral (rat) 200 mg/kg (palladium chloride) ;LC50 intratracheal (rat) 6 mg/kg (palladium chloride) |
| Specific gravity | 12.03 |
| Odor | Odorless |
| resistivity (resistivity) | 9.96 μΩ-cm, 20°C |
| Merck | 14,6989 |
| NIST chemical information | Palladium(7440-05-3) |
| EPA chemical information | Palladium (7440-05-3) |
Introduction
Palladium is a transition element between group III (nickel group) and light platinum metal in the periodic table. It is a silver-white metal with medium hardness, medium wrought and ductile. Palladium is the intermediate element in the transition element group 10 (periods 4, 5 and 6). Many of its properties are similar to the nickel located above it and the platinum located below it in this group. Palladium is a soft silver-white metal whose chemical and physical properties are very similar to those of platinum. It has ductility and ductility, which means it can be processed into flakes and stretched into very fine wires by die. Palladium is soluble in aqua regia, hot nitric acid, sulfuric acid, slightly soluble in hydrochloric acid, insoluble in cold water and hot water.
Discovery history
Palladium was discovered by W.H. in 1803. Wollaston during the refining and purification of platinum metals. This new metal was found in aqua regia extract of natural platinum, and was detected in solution after platinum precipitation. It was removed as ammonium chloroplatinate. The solution was treated with mercurous cyanide and the yellow palladium complex salt was precipitated. The precipitate is washed and ignited to form palladium metal. Wollaston named Palladium after the newly discovered asteroid Pallas.
Source
palladium is considered a rare metal, accounting for only about 1 part of every 0.1 billion parts of the earth's crust. Although it is rarely found in its pure state, it is considered to be the 77th most abundant element on earth. Instead, it is mixed with other metals or palladium compounds. It was first discovered in gold mines in Brazil, which miners believe were contaminated by what they call "platinum. Later, it was considered an alloy combination of palladium and gold. Ore deposits containing palladium as well as other metals have been found in Russia, Canada and South Africa in the Siberian and Ural Mountains, as well as in South America. Palladium in nature is always associated with other platinum group metals. Its abundance in the earth's crust is estimated to be 0.015 mg/kg, which is about three times that of platinum. Palladium occurs in the form of six isotopes: 102Pd(1.0%),104Pd(11%),105Pd(22.2%),106Pd(27.3%),108Pd(26.7%) and 110Pd(11.8%). Small amounts of palladium can be found in the lithosphere in the form of natural palladium and alloaluminum palladium, PdPt and PdAu alloys, and in the form of contaminants of silver and nickel ores.
storage precautions
Palladium and carbon should always be treated in an inert atmosphere (preferably argon), and the reaction vessel should be flushed with inert gas before adding the catalyst. It is forbidden to add the dried catalyst to the organic solvent in air. The carbon-loaded palladium recovered from the catalytic hydrogenation reaction by filtration needs to be handled carefully because it is usually saturated with hydrogen and will spontaneously ignite when exposed to air. Do not dry the filter cake, add wet material to a large amount of water and handle it properly.
Preparation
Palladium can be made from ore by dry method in industrial production; it can also be prepared from copper and nickel sulfide ore. In the production process, nickel is used as a by-product as a raw material and is wet smelted. It can also be obtained by producing nickel from copper sulfide ore or nickel sulfide ore by-products of wet method and copper. The wet method uses the extracted nickel and copper residues as raw materials, adds water for extraction, filtration, and then adds ammonia water and hydrochloric acid for reaction to form ammonium chloropalladium acid precipitation. After refining and filtering, the final product palladium obtained by reducing ammonium chloropalate with 99.95% palladium of hydrogen can be obtained.
Production method
Industrial production can be made from ore by dry method; it can also be made from copper and nickel sulfide ore. By-products generated in the production process of copper and nickel can be used as raw materials and produced by wet smelting.
The wet method uses the residual components after the extraction of nickel and copper as raw materials, adds aqua regia for extraction, filters, and adds ammonia and hydrochloric acid to the filtrate for reaction to generate ammonium chloropalladium acid precipitation. After refining, filtration, ammonium chloropalladium acid is reduced with hydrogen to produce about 99.95% palladium products.
| auto-ignition temperature | >1120 °F |
| toxic substance data | 7440-05-3(Hazardous Substances Data) |