6 10月 2010

Oxidize cerium

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Oxidize cerium
Yellowish or yellow brown helps powder. Density 7. 13g/ cm3. The fusing point is 2397 ¡æ. Not soluble in alkali of hydration, is soluble in the acid a little. At ¡æ temperatures and 15Mpa pressures 2000, can get and oxidize two cerium three times with the cerium oxide of hydrogen reduction, the temperature is dissociated among ¡æ2000, the pressure is dissociated in 5Mpa pressure, it is a little yellow and slightly rufescent that the cerium oxide is presented, there is pink, its characteristics are to do the polishing material.
Catalogue
Main function in various glass of rare earth
The properties of the rare earth element
Main function in various glass of rare earth
The properties of the rare earth element
Expansion
Detailed content name: Cerium oxide; cerous oxide
Molecular formula: Ce02
Molecular weight: 172. 13
CAS number: 12014-56-1
Specification:
Divided into according to the purity: It is low and pure: The purity is not higher than 99%, high pure: 99.9% ~99.99% , Extremely high pure more than 99.999%
Divided into according to the graininess: Coarse powder, mm level, inferior nanometer range, nanometer range
Prove safely: The products are nonpoisonous, tasteless, has not stimulated, safe and reliable, the characteristic is steady, no chemical reaction will take place with water and organic matter, it is high-quality glass clarifier, decolorant and chemical assistant.
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Main function in various glass of rare earth
( 1) The rare earth polishes function
? ? The polishing powder of rare earth polishes the fast, highly polished and long advantage of life time, compared with traditional polishing powder - iron rouge, do not pollute the environment, easy from dipping in the advantage of removing etc. on things. Polish the lens with the polishing powder of cerium oxide, the work capacity finished in one minute, if need 30- 60 minutes with the polishing powder of ferric oxide. So, polishing powder of rare earth has consumption little and polishing fast and polishing the efficient advantage. And can change and polish quality and operating environment. The polishing powder of general rare-earth glass mainly uses rich cerium oxide. The cerium oxide the reason why it is that the extremely valid polishing uses compounds, because it can rub against machinery by chemical decomposition two kinds of forms polish the glass at the same time. The cerium polishing powder of rare earth is used in the polishing of camera, camera lens, teletube, eyeglass,etc. extensively. Our country has dozens of polishing powder factories of rare earth at present, more than ten home of more than one hundred tons in production scale. The clear American rare earth polishing powder limited company of northern tribe or its ruler of Baotou of the Sino-foreign joint venture is one of the rare earth polishing powder factories of maximum at present our country, 1200 tons of annual production capacity, products are sold to domestic and foreignly.
( 2) The glass is decolorized
? ? Contain ferric oxide in all glass, it can bring into the glass through the glass cullet in raw materials, grit, limestone and glass batching, there are two kinds of its occurring form: One to make glass color turn dark blue ferrous iron into, another kind of make glass color turn into ferric irons of the yellow, decolourization is to oxidize bivalent Fe ions into the ferric iron, because of only ferrous 1/10 of ferric tone intensity. Then add complementary color pharmaceutical and neutralize the color into light green color.
? ? It is mainly cerium oxide and neodymium oxide to be used in the rare earth element that the glass decolorizes. Rare-earth glass decolorant replaces white arsenic decolorant that tradition used, not merely raise the efficiency, and avoided the pollution of white arsenic. It has advantages such as stable, cheap and non-absorbing visible light of high temperature behavior,etc. that the cerium oxide is used in the glass and decolorize.
( 3) The glass is coloured
? ? Rare-earth ion has stable and bright colors under the high temperature, are used for while mixing the material liquid, make the glass of different colors. Rare earth oxide such as neodymium, praseodymium, erbium, cerium are the extremely good glass colourant, when the transparent glass which adds the colourant of rare earth absorbs the wavelength as 400- 700 nanometers of visible light, the ones that appear beautifully are colored. Can make aviation and navigation, instruction lamp shades of different means of transportation and various advanced artistic adornments with the colored glasss.
? ? Neodymium oxide is added into sodium - calcium glass and lead glass, the depth of the glass color depends on the content of vitreous thickness and neodymium and power of the light source, the thin glass is light and pink, the heavy sheet glass is blue and purple, it is double-colored that this kind of phenomenon is called neodymium; Praseodymium oxide produced a kind and is like in the green of chromium; It is pink to use in photochromic glass and crystal glass erbium oxide; The cerium oxide is used in combination with titanium dioxide, make the glass yellow; Praseodymium and neodymium oxide oxide can be used in the neodymium welding glass of praseodymium.
( 4) Rare earth clarifier
? ? Replace traditional arsenic oxide with cerium oxide and make glass clarifier, remove bubble and trace and take the color element, result prominent while preparing colourless vial, finished product brilliant and glimmering and pure white raising by the intersection of diaphaneity and kind glass intensity and heat resistance. Also dispelled arsenic to environment and vitreous pollution at the same time.
? ? In addition, the cerium oxide is added in the daily glass, such as the building and glass for vehicle, crystal glass, can reduce the light transmittance of the ultraviolet ray, this use has already been popularized in Japan and U.S.A.. With the improvement of the quality of life in our country, there are better markets too. Neodymium oxide is added in the glass bulb of the kinescope, can dispel the dispersion of light of red, have increased sharpness. The special glass which adds the rare earth is as follows, the lanthanum glass has high refracting, low dispersion characteristicses, are used for making various lens, advanced camera, lens extensively, especially the lens of the high altitude photographing apparatus; The radiation shielding glass of cerium, are used in glass of car and TV glass bulb; The neodymium glass is used in laser material, it is the optimal material of huge laser, used mainly in the controlled kernel fusionfacility.
( 5) Can get certain application in the fuel cell.
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The properties of the rare earth element
The properties of the rare earth element are decided by the rare earth atom and ionic electronic structural features of rare earth. The properties of the rare earth element are and existence and distribution form in the nature of rare earth element, method and rare earth element that rare earth element separate employ close and associated extensively in various fields. In order to understand rare earth element separation and applied principle better, it is necessary for us to study the rare earth element (metal and +3 price ion) first Physical and chemical properties. Rare earth elements are all typical metal, generally silver, its metallic reflection is between iron and silver. Some can form with salt of the color metal have faint yellow slightly among them ' For instance praseodymium, neodymium,etc.) . Rare earth metal texture is soft, as soft as cerium, lanthanum and tin, but have the tendency to harden gradually as the atomic number increases. Rare earth metal has ductility, among them cerium, samarium, ytterbium ductility are good, for example cerium can be well rolled into a flake breakage filament. The majority of rare earth metal presents crystalline grain of close Six Party or lattice structure of the face-centered cubic, only samarium is the rhombic structure, europium is the body-centred cubic structure. Rare earth metal ( Besides europium, ytterbium) Density and rare earth metal ( Besides lanthanum, europium, ytterbium) Fusing point with increase of the atomic number increase. In terms of its density, regard scandium as minimum, yttrium and take second place, and thulium and lutetium maximum, this conforms with radial variation tendency of their atom. Their boiling point, have the lowest ytterbium, lanthanum and cerium is the highest.