ニッケル

解説ニッケル,銀白色，通常は面心立方格子．密度8.902 g cm－3(25 ℃)．融点1453 ℃，沸点2732 ℃．標準電極電位 Ni2＋/Ni－0.257 V．第一イオン化エネルギー7.635 eV．鍛造，鍛接ができ，展延性に富む．立方格子のものは強磁性だが，鉄よりは弱い．キュリー温度は358 ℃．金属結合半径0.125 nm．Ni2＋(六配位)0.083 nm．森北出版「化学辞典（第2版）

用途ラネーニッケル触媒の原料。

用途高純度金属、合金材料。

用途2007年における世界のニッケル消費量は132万トンであり、そのうち日本は13％を占める。純金属として実験器具や家具などの材料に、まためっき用として金属表面の保護に用いられる。微粉末状のものは水素を吸蔵するので、水素添加用触媒として用いられる。しかしそれ以上に各種の合金の成分としての需要のほうが多く、たとえば、洋銀、ニクロム、コンスタンタン、マンガニン、ニッケリンなどの合金として多方面に用いられるほか、鋼に添加してニッケル鋼、ニッケルクロム鋼、ステンレス鋼、耐熱鋼、磁石鋼などの特殊鋼が製造される。

天然物の起源Nickel is the 23rd most abundant element found in the Earth’s crust. It is somewhat plentiful but scattered and makes up one-hundredth of 1% of igneous rocks. Nickel metal is foundin meteorites (as are some other elements). It is believed that molten nickel, along with iron,makes up the central sphere that forms the core of the Earth.There are several types of nickel ores. One is the major ore for nickel called pentlandite(NiS 2FeS), which is iron/nickel sulfide. Another is a mineral called niccolite (NiAs), discovered in 1751 and first found in a mining area of Sweden. By far, the largest mining area fornickel is located in Ontario, Canada, where it is recovered from what is thought to be a verylarge meteorite that crashed into the Earth eons ago. This large nickel deposit is one reasonfor the theory of the Earth’s core being molten nickel and iron, given that both the Earth andmeteorites were formed during the early stages of the solar system. Some nickel ores are alsofound in Cuba, the Dominican Republic, and Scandinavia. Traces of nickel exist in soils, coal,plants, and animals.

使用Nickel-plating; for various alloys such as new silver, Chinese silver, German silver; for coins, electrotypes, storage batteries; magnets, lightning-rod tips, electrical contacts and electrodes, spark plugs, machinery parts; catalyst for hydrogenation of oils and other organic substances. See also Raney nickel. manufacture of Monel metal, stainless steels, heat resistant steels, heat and corrosion resistant alloys, nickel-chrome resistance wire; in alloys for electronic and space applications.

一般的な説明Nickel catalyst, is extremely fine powdered nickel. Nickel is grayish colored. Insoluble in water. Nickel catalyst is used to promote the chemical action in manufacturing synthetics and to process vegetable oil and petroleum. If exposed to air or moisture, Nickel may become hot enough to ignite. Nickel is insoluble in water and does not react with larger volumes of water.

用途クロムなどとの合金によるステンレス鋼や耐熱鋼等が最大の用途 で、硬貨から電子産業まで幅広い活躍Ni の用途の約 70％はステンレス鋼で原料として主にフェロニッケル （FeNi）が用いられる。Ni 地金は特殊鋼（LNG タンク、自動車、船舶、機械向 け構造用合金鋼）、ガスタービン用Ni基耐熱合金、メッキ、磁性材料（アルニ コ磁石）等で利用される。硫酸 Ni 等の Ni 化合物が磁性材料、電池材料（Ni 水素電池、リチウムイオン電池（以下 LIB）の正極材）、触媒材料として使用 されている。「洋白・洋銀」（銅・Ni・亜鉛合金）は食器、貨幣などに古くから使 用されてきた。めっきは 19 世紀に実用化された。その後、合金の開発が進 みステンレス産業の発展に伴い需要が増大している。

Nickel is obtained by processing sulfide and laterite ore concentrates using pyrometallurgic and hydrometallurgic processes. The resultant nickel matte obtained by roasting and smelting is subjected to further cleaning by electro-, vapo-, and hydrometallurgic refining methods. Some portion of the matte is roasted to obtain commercial nickel oxide agglomerate. Pure, 99.9% nickel can be obtained by electrolytic refining process. The most pure, 99.97%, nickel is obtained by vapometallurgy. In this process, known also as the Mond method,nickel and copper sulfide blend is converted to oxides and then reduced by heating with water gas at 350–400°C. The resultant active form of nickel is treated with carbon monoxide to give volatile nickel carbonyl [Ni(CO)4]. The latter reaction is reversible; heating results in pure nickel and carbon monoxide.

製造方法The carbonyl process is most commonly employed when very pure nickel is required. The impure metal is reacted with pure carbon monoxide at 50° and the carbonyl produced fractionated several times prior to pyrolysis at around 200°. The nickel thus obtained has a purity of 99.90-99.99% depending upon the materials used. Electrolytic methods for producing high purity nickel depend upon the production of high purity nickel salts. The nickel obtained by the electrolysis of pure nickel chloride solution with inert platinum-iridium anodes is 99.99% pure.