Rare Earth Metals https://www.joysine.com A professional producer from China! Sun, 12 Nov 2017 01:20:43 +0000 en-US hourly 1 https://www.joysine.com/wp-content/uploads/2017/10/cropped-joysineico-2-32x32.png Rare Earth Metals https://www.joysine.com 32 32 rare earth polishing powder factory in China https://www.joysine.com/rare-earth-polishing-powder-factory/ Tue, 31 Oct 2017 03:18:04 +0000 https://www.joysine.com/?p=1110 At present, the main products include Rare earth oxide: lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, lutetium, holmium, erbium, ytterbium, thulium, yttrium, scandium; Inorganic oxide: cobalt oxide, nickel oxide, bismuth oxide, tantalum oxide, niobium oxide, germanium oxide,gallium oxide, indium oxide. Our products are widely applied to fields such as ceramics, glass, construction material, petrochemical, metallurgical machinery, superconducting material, textile rubber, aerospace, atomic energy, infrared laser, polishing and fluorescent materials.

Rare Earth Catalog  Download   MSDS Download

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General description of rare earth https://www.joysine.com/general-description-of-rare-earth/ Mon, 16 Oct 2017 14:44:37 +0000 https://www.joysine.com/?p=1000 General description of rare earth

Rare Earth Oxides

RE oxide are most stable from various RE compounds, the fundamental raw material of other compounds and are basic products of raw material in RE industry. RE oxides are generally prepared by ignition of corresponding hydroxide, oxalate, carbonate salt, nitrate salt, soleplate salt in the air. RE oxide are insoluble in water and basic solution, soluble in strong mineral acids, and apt to absorb cabin dioxide from air to form carbonate salt. All RE oxide are powder and their melt points are above 2300℃.

Rare earth hydroxides

RE Hydroxides are generally prepared by mixing corresponding soluble salt with ammonium hydroxide or sodium hydroxide they are soluble in acids, insoluble in water, and generally powder.

Rare earth Chlorides

There are two kinds of RE chlorides, anhydrous and hydrous chlorides. The former is prepared by heating, dewater in vacuum of it’s hydrous. The Later is prepared by condensing of its corresponding RE chloride solution. All RE chlorides are hydroscopic and substantially soluble in water.

Rare earth Sulphates

RE sulphates are generally prepared by adding sulphuric acid to their corresponding oxides, hydroxides, carbonates, and the solid state of the salt can be prepared by condensation of the solution. All RE sulphates are soluble in water, but their solubilities are lower and down with the temperature up.

Rare earth Carbonate

The solid RE carbonate can be prepared by adding more the solution of soluble RE salt. RE carbonates are little soluble in water, soluble in acids to yield corresponding salt and give off CO2 RE carbonates decompose to be oxides over 905℃.

Rear earth Nitrate Hydrous

RE nitrates can be prepared by condensing the solution of their salt which are obtained by mixing the nitric acid and RE oxide, hydroxide, carbonate. RE nitrates are most soluble in water of various salt and soluble in some organic agents-alcohol acetone etc. When the salts are heated, give off 02,NO,N02,the final products are oxides.

Rear earth Fluorides

RE fluorides are prepared by adding HF solution RE salt solution are insoluble in water, soluble in thick acid, and the major raw material for electrolysis of RE metal.

Rear Earth Metals

RE metals appear as of typical metallicity. Their melt points and densities increase with the atomic number except Europium and ytterbium, yet the hardness increases with the atomic number in spite of being soft. Although their tensile stresses are low, RE metals show fairly high stretchy .The activities of the Metals increase in sequence in Sc,Y,La, however decrease from La to Lu sequentially. The metals are liable to oxidize in the air, inert in cool water, but active to hot water and realease hydrogen and violently react with acids, but rather inactive to bases. The metals are combustible. As such should be kept carefully. Normally, RE metals are manufactured by electrolysis or pyroreduction. RE metals are rather effective reductants in metallurgical, the metals have been used to prepare high performance magnetics, fuel batteries, secondary cells, and functional non-ferrous materials.

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Which elements are rare earth element? https://www.joysine.com/which-elements-are-rare-earth-element/ Mon, 16 Oct 2017 14:43:24 +0000 https://www.joysine.com/?p=997 Which elements are rare earth element?

Rare earth is a periodic table of the chemical elements in the lanthanide and their associated and similar elements collectively, which comprises lanthanum ( La ), cerium ( Ce ), praseodymium ( Pr ),neodymium ( Nd ),promethium ( Pm ), samarium( Sm ) , europium ( Eu ), gadolinium ( Gd ), terbium ( Tb ), dysprosium ( Dy ) , holmium ( Ho ) ,erbium ( Er ), thulium ( Tm ),ytterbium  ( Yb ),lutetium ( Lu ), as well as with lanthanide 15 elements are closely related to the two elements of scandium ( Sc ) and yttrium ( Y ) a total of 17 kinds of elements, called rare earth elements ( Rare Earth ), rare earth ( RE ).

Rare earth element is originally from Sweden made scarce mineral found in the ” soil “, according to the custom of the time, called the insoluble substance, so rare.

According to rare earth elements atomic layer structure and physical and chemical properties, and their mineral symbiosis and different ionic radius can have different properties, seventeen kinds of rare earth elements are usually divided into two groups.

( also called light rare earth cerium group ) include: lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, pm.

Heavy rare earth ( also known as Y group ) include: terbium, dysprosium, holmium erbium, thulium, ytterbium, lutetium, scandium, yttrium.

Said cerium group or yttrium group, because the mineral is obtained by separation of rare earth mixture, the two content more.

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Rare earth oxides formula weight https://www.joysine.com/rare-earth-oxides-formula-weight/ Mon, 16 Oct 2017 14:42:05 +0000 https://www.joysine.com/?p=995 Rare earth oxides formula weight
AtomicSymbol AtomicNumber AtomicWeight Rare earthOxide F.Wt Half F.Wt
La 57 138.905 La2O3 305.8 162.9
Ce 58 140.12 CeO2 172.1 172.1
Pr 59 140.908 Pr6O11 1021.4 170.2
Nd 60 144.2 Nd2O3 336.4 168.2
Sm 62 150.4 Sm2O3 348.8 174.4
Eu 63 151.96 Eu2O3 351.9 176.0
Gd 64 157.2 Gd2O3 362.4 181.2
Tb 65 158.925 Tb4O7 747.7 186.9
Dy 66 162.5 Dy2O3 373.0 186.5
Ho 67 164.93 Ho2O3 377.9 188.9
Er 68 167.2 Er2O3 382.4 191.2
Tm 69 168.93 Tm2O3 385.87 192.93
Yb 70 173 Yb2O3 394.0 197.0
Lu 71 174.96 Lu2O3 397.9 199.0
Sc 21 44.9559 Sc2O3 137.91 69.0
Y
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Rare earth standard electrode potential https://www.joysine.com/rare-earth-standard-electrode-potential/ Mon, 16 Oct 2017 14:40:08 +0000 https://www.joysine.com/?p=993 Rare earth standard electrode potential
Acidic solution V Alkaline solution V
La3++3e=La -2.522 La(OH)3+3e=La+3OH -2.9
Ce3++3e=Ce La(OH)3+3e=La+3OH
Ce4++e=Ce3+ La(OH)3+3e=La+3OH
Pr3++3e=Pr La(OH)3+3e=La+3OH
Nd3++3e=Nd La(OH)3+3e=La+3OH
Sm3++3e=Sm La(OH)3+3e=La+3OH
Sm3++e=Sm2+ La(OH)3+3e=La+3OH
Eu3++3e=Eu La(OH)3+3e=La+3OH
Gd3++3e=Gd La(OH)3+3e=La+3OH
Tb3++3e=Tb La(OH)3+3e=La+3OH
Dy3++3e=Dy La(OH)3+3e=La+3OH
Er3++3e=Ho La(OH)3+3e=La+3OH
Ho3++3e=Er La(OH)3+3e=La+3OH
Tm3++3e=Tm La(OH)3+3e=La+3OH
Yb3++3e=Yb La(OH)3+3e=La+3OH
La3++3e=La La(OH)3+3e=La+3OH
La3++3e=La La(OH)3+3e=La+3OH
La3++3e=La La(OH)3+3e=La+3OH
La3++3e=La La(OH)3+3e=La+3OH
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Cerium oxide polishing powder production https://www.joysine.com/cerium-oxide-polishing-powder-production/ Mon, 16 Oct 2017 14:37:48 +0000 https://www.joysine.com/?p=990

Development history

With the development of rare-earth industry, in twentieth Century 30 time, first appeared in Europe by rare earth oxide polishing powder for polishing glass. In the Second World War, rare earth polishing powder quickly in the polishing precision optical instrument to succeed. Because of the rare earth polishing powder with high polishing efficiency, good quality, less pollution, stimulated western research enthusiasm. Thus, rare earth polishing powder to replace the traditional trend of rapid development of polishing powder. Foreign 60 years ago to begin production of rare earth polishing powder, in twentieth Century 90 time already formed a variety of standardized, serialized products amounted to 30 a variety of. At present, foreign rare-earth polishing powder manufacturers mainly has 15 ( annual production capacity of 200 tons. Among them, the French Rhodia Inc annual production capacity of 2200 tons, is currently the world’s largest rare earth polishing powder manufacturer. The United States of America polishing powder with an annual output of 1500 tons or more. Japanese production of rare earth polishing powder raw material using bastnaesite, coarse cerium chloride and rare earth chloride three, technology each are not identical. Japan rare-earth polishing powder on sintering equipment and technology are most characteristic. In 1968, China in Shanghai chemical plant Yuelong first successful preparation of rare earth polishing powder.

Composition and structure of

Cerium oxide polishing powder is defined by a group composed of cerium oxide polishing powder, cerium oxide polishing powder as main component in two cerium oxide ( CeO2 ), followed by lanthanum oxide, praseodymium oxide ( La2O3 ) ( Pr2O3 ), also contains trace amounts of silica, alumina and calcium oxide, and some types of polishing powder for polishing performance to join 3-7% fluoride.

Under electron microscopy of cerium oxide polishing powder crystal structure

Cerium oxide polishing powder and the use of

1, in addition to cerium oxide polishing powder, polishing powder and other materials: polishing powder usually consists of cerium oxide, alumina, silicon oxide, iron oxide, zirconium oxide, chromium oxide and other components, different materials of different hardness, in the water chemical properties are also different, therefore the use of occasions each not same. Alumina and chromium oxide Mohs hardness 9, cerium oxide and zirconium oxide is 7 lower, iron oxide. Cerium oxide and silicate glass with high chemical active, hardness is also quite, it is widely used in glass polishing.

2, cerium oxide particle size: size bigger cerium oxide, grinding force increases, more suitable for harder materials, ZF glass should be used fine polishing powder. Note that, all of the cerium oxide particles have an average particle size distribution, or median diameter of D50 size determining only the polishing speed, while the maximum size Dmax determines the polishing precision. Therefore, in order to obtain high accuracy requirement, must control the maximum particle polishing powder.

3, The polishing powder real hardness: hardness associated with the material, such as cerium oxide hardness is hardness of about 7, all sorts of cerium oxide are almost. But different cerium oxide body give people the feeling of different hardness, is because of cerium oxide polishing powder usually aggregate, drawings for a polishing powder dimerization electron microscope photos. As a result of firing temperature different, aggregate strength is not the same, so use will have a hardness of not the same feeling. Of course, some polishing powder adding alumina and other hard materials, demonstrated the grinding rate and the wear resistance are improved.

4, In a polishing slurry concentration: polishing slurry in the process of concentration determines the speed of polishing, the polishing speed higher concentration. The use of small particles of polishing powder, slurry concentration by appropriate reduction.

5, cerium oxide polishing powder, polishing mold choice: polishing die should use soft point. It should be pointed out that, a lot of polyurethane polishing disc adding cerium oxide polishing powder. The maximum particle size of polishing powder also determines the final polishing precision. In my, preferably using without polishing powder, polishing mould.

Effect of cerium oxide polishing powder properties

1, powder particle size: determines the polishing precision and speed, commonly used the number of heads and powder average particle size. Sift sieve mesh can grasp the powder relative granularity value, average particle size of polishing powder particle size determines the overall level.

2, powder: hardness Mohs hardness of relatively large powder has the advantages of high cutting efficiency, while adding some auxiliary grinding agent, also can improve the cutting effect; different applications will have very big discrepancy, including its processing technology.

3, powder suspension: good powder for polishing powder have better suspension, shape of the powder and particle size on the suspension performance has a certain impact, sheet and fine particle size of polishing powder suspension relative to be friends with some, but not for the. Polishing powder suspension performance enhancement can also be added to improve the suspension ( agent ).

4, powder: powder crystal polymorphs is together single crystal particles, determines the powder cutting performance, wear resistance and fluidity. Powder agglomeration together in a single crystal particles in the polishing process separation (broken ), so that its cutting resistance, abrasion resistance decreased gradually, irregular hexagonal crystal particles having excellent cutting performance, wear resistance and fluidity.

5, color: raw materials and the content of Pr and calcination temperature and other factors, praseodymium content is higher, the powder was red brown. Low polishing powder contains large amounts of praseodymium ( cerium praseodymium material ), it was red brown. Polishing powder, ignition temperature is high, its significant partial white pink, low temperature ( about 900 degrees ), it was a pale yellow.

To sum up, in order to increase the cerium oxide polishing powder, polishing speed, usually in cerium oxide polishing powder adding fluoride to increase grinding efficiency. The lower cerium content of mixed rare earth polishing powder often combined with 3 – 8 fluorine; pure cerium oxide polishing powder is usually not doped with fluorine. On ZF or F series of glass, because of their lower hardness, but also the material itself is a high fluoride content, therefore because of choosing a fluoride-free polishing powder as well.

Production of raw materials

At present, China’s production of cerium rare earth polishing powder raw materials are the following: ( 1) the cerium oxide ( CeO2 ), made from a mixture of rare-earth salts after separation of income ( w ( CeO2 ) =99% );

( 2) mixed rare-earth hydroxide ( RE ( OH ) 3), is a rare earth concentrate ( w ( REO )≥50%) after chemical treatment of intermediate raw materials ( w ( REO ) =65%, w ( CeO2 )≥ 48% );

( 3) the mixed rare earth chloride ( RECl3 ), from mixed rare earth chloride extraction separation of the rare earth chloride without europium (mainly including La, Ce, Pr and Nd, w ( REO )≥ 45%, w ( CeO2 )≥ 50% );

( 4) high grade rare earth concentrate ( w ( REO )≥ 60%, w ( CeO2 )≥ 48% ), Inner Mongolia Baotou rare earth concentrate, the Weishan in Shandong and Sichuan Mianning bastnaesite concentrate.

Production process

( 1) high CE rare-earth polishing powder

In the rare earth mixture after the separation of cerium oxide as raw materials, physical and chemical method in processing high hardness, uniform particle size, small, a face-centered cubic crystal powder products.

The main process is: raw material, high temperature calcining→→→water quenching hydraulic classification, filtering, drying and high cerium rare earth polishing powder products. The main equipment are: calcination furnace, water quenching tank, classification, filter, drying box. Main measures: products w (REO ) =99%, w ( CeO2 ) =99%; rare earth recovery rate of about 95%. The product is suitable for high speed polishing. This polishing powder first instead of the classical polishing iron oxide powder ( pink ).

( 2) in cerium rare earth polishing powder preparation

Mixed rare earth hydroxide ( w ( REO ) =65%, w ( CeO2 )≥ 48% ) as raw material, in the process of chemical pretreatment of rare earth salt solution, adding intermediates ( agent ) that is transformed into w ( CeO2 ) =80% ~ 85% intermediate cerium rare earth polishing powder products. The technological process for:

Raw material, oxidation, and dissolving and filtering to acid dissolution, precipitation, washing filter high temperature calcination, grinding and screening, intermediate cerium rare earth polishing powder products.

The main equipment are: oxidation tank, and melting trough, acid dissolving tank, precipitation tank, filter, calcining furnace, fine grinding and sieving machine and a packing machine.

Main measures: products w (REO ) =90%, w ( CeO2 ) =80% ~ 85%; rare earth recovery rate of about 95%; the average particle size of 0.4 microns to 1.3 microns. The product is suitable for high speed polishing, than high cerium rare earth polishing powder high-speed polishing performance more excellent.

( 3) low cerium rare earth polishing powder preparation

With little europium rare earth chloride ( w ( REO )≥ 45%, w ( CeO2 )≥ 48% ) as raw materials, to synthesis intermediates ( precipitation ) of salt precipitation process, can process for preparing low cerium rare earth polishing powder products.

The main process is: raw material, dissolving, salt precipitation, filtration and washing, high temperature calcination, crushing, screening, grinding low cerium rare earth polishing powder products.

The main equipment are: dissolving tank, precipitation tank, filter, calcining furnace, mill, fine grinding and sieving machine.

Main measures: products w ( REO ) =85% ~ 90%, w ( CeO2 ) =48% ~ 50%; rare earth recovery rate of about 95%; the average particle size of 0.5 microns to 1.5 microns.

At present, the domestic production of low-grade cerium rare earth polishing powder amount is maximum, the total yield of more than 90%.

Application fields

As a result of cerium rare earth polishing powder has excellent chemical and physical properties, so in the industrial products polishing has obtained the widespread application.

And is mainly used for flat glass, sheet glass, craft glass polishing. Optical glass, glasses, glass mold polishing. Precision optical glass, TN, STN, LCD glass substrate, precision optical lens polishing. Prism, lens, projector lens polishing. LCD LCD glass, TFT, ITO, IC conductive glass photomask and other high precision polishing, can also be applied to metal polishing, jewelry, lighting and other industries parts rough polishing.

·the high cerium rare earth polishing powder, mainly used in precision optical lens polishing. The polishing powder of excellent performance, good polishing effect, high price. Cerium in rare earth polishing powder, mainly applied to optical instruments of small spherical lens with medium precision high speed polishing, the polishing powder and high cerium powder, can make the polishing liquid concentration decreased by 11%, the polishing rate increases by 35%, products can improve smoothness level, polishing powder using life can be raised 30%. Low cerium rare earth polishing powder, suitable for the television picture tubes, glasses and flat glass polishing.

Selection of cerium oxide polishing powder

Selection of polishing powder according to the polishing material, as well as the polishing precision requirements, selecting appropriate models of polishing powder.

According to the hardness of similar phase polishing principle, for different materials hardness of glass to use the corresponding models of polishing powder. There is also based on the polishing precision requirements, selection of different size range of polishing powder, particle size index are the main center of grain size D50, and D10, D90 etc.. Particle size distribution test report peak range of smaller, more focused. The center than the small size particles on the polishing of no effect, than in the center of big diameter particles on the polishing surface scratches, so the particle size distribution is a important index.

In addition, the content of cerium oxide polishing powder on polishing performance have certain effect, but have different polishing material to use to adapt the content of cerium oxide polishing powder, polishing its effect will be better.

Polishing powder using process generally is water or other media as a carrier, but in the solution, so the suspension in water is also very important, the suspension of poor polishing powder into the bottom of the container cannot follow solution circulation use, so the cerium oxide polishing powder suspension on polishing performance also has a great influence on.

There is a polishing powder pH indicator is to ensure that the polishing process on human security.

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The Application of Rare Earth https://www.joysine.com/the-application-of-rare-earth/ Mon, 16 Oct 2017 14:33:09 +0000 https://www.joysine.com/?p=951 The Application of Rare Earth

Rare earth materials with special chemical and physical properties, so it has a wide range of applications in material, chemical, and nuclear energy, such as its main function is to improve the material performance and activity, it’s main application:

1.Metallurgy: de-oxygen de-sulfur, and other injurious ingredients to act reducing agent.

2.Flint, ignition device

3.catalyst for petroleum cracking process

4.Purifying automobile exhaust gas

5.Glass precipitating and decoloring agents

6.Permanent magnets SmCo,NdFeB

7.Super-conductor

8.Functional ceramic, yttria+zirconia

9.Phosphor for color TV, ceria+zirconia

10.Hydrogen storage, secondary battery

11.Polishing powder

12.Laser material, optical fiber optical lens

13.Magnetic memory materials

14.Substitution of poisonous Cd pigments

15.Environmental protection:plastics degradation,paint and ink drier

16.Laser materials

17.Agriculture

A table listing the seventeen rare earth elements, their atomic number and symbol, and their main usages (see also Technological applications) is provided here. Some of the rare earths are named after the scientists who discovered or elucidated their elemental properties, and some after their geographical discovery.

Symbol Name Selected applications
21 Sc Scandium Light aluminium-scandium alloy for aerospace components, additive in Mercury-vapor lamps.[4]
39 Y Yttrium Yttrium-aluminium garnet (YAG) laser, yttrium vanadate (YVO4) as host for europium in TV red phosphor, YBCO high-temperature superconductors, yttrium iron garnet (YIG) microwavefilters.[4]
57 La Lanthanum High refractive index glass, flint, hydrogen storage, battery-electrodes, camera lenses, fluid catalytic cracking catalyst for oil refineries
58 Ce Cerium Chemical oxidizing agent, polishing powder, yellow colors in glass and ceramics, catalyst forself-cleaning ovens, fluid catalytic cracking catalyst for oil refineries, ferrocerium flints for lighters
59 Pr Praseodymium Rare-earth magnets, lasers, core material for carbon arc lighting, colorant in glasses andenamels, additive in didymium glass used in welding goggles,[4] ferrocerium firesteel (flint) products.
60 Nd Neodymium Rare-earth magnets, lasers, violet colors in glass and ceramics, ceramic capacitors
61 Pm Promethium Nuclear batteries
62 Sm Samarium Rare-earth magnets, lasers, neutron capture, masers
63 Eu Europium Red and blue phosphors, lasers, mercury-vapor lamps, NMR relaxation agent
64 Gd Gadolinium Rare-earth magnets, high refractive index glass or garnets, lasers, X-ray tubes, computer memories, neutron capture, MRI contrast agent, NMR relaxation agent
65 Tb Terbium Green phosphors, lasers, fluorescent lamps
66 Dy Dysprosium Rare-earth magnets, lasers
67 Ho Holmium Lasers
68 Er Erbium Lasers, vanadium steel
69 Tm Thulium Portable X-ray machines
70 Yb Ytterbium Infrared lasers, chemical reducing agent
71 Lu Lutetium PET Scan detectors, high refractive index glass

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Physical properties of rare earth metal https://www.joysine.com/physical-properties-of-rare-earth-metal/ Mon, 16 Oct 2017 14:30:23 +0000 https://www.joysine.com/?p=948 Physical properties of rare earth metal
AtomicNumbe AtomicSymbol AtomicWeight Ionic Radius(A) Density
(g/cm3)
Melting Point (oC) Boiling Point(oC) Oxide’s Melting Point(oC) Specific Resistance Magnetic Moment Thermal Neutron Capture Cross Section
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
21
39
La
Ce
Pr
Nd
Pm
Sm
Eu
Gd
Tb
Dy
Ho
Er
Tm
Yb
Lu
Sc
Y
138.92
140.13
140.92
144.27
147.00
150.35
152.00
157.26
158.93
162.51
164.94
167.27
168.94
173.04
174.99
44.97
88.92
1.22
1.18
1.16
1.15
1.14
1.13
1.13
1.11
1.09
1.07
1.05
1.04
1.04
1.00
0.99
0.83
1.06
6.19
6.768
6.769
7.007

7.504
5.166
7.868
8.253
8.565
8.799
9.058
9.318
6.959
9.849
2.995
4.472
920+/-5
804+/-5
935+/-5
1024+/-5

1052+/-5
826+/-10
1350+/-20
1336
1485+/-20
1490
1500~1550
1500~1600
824+/-5
1650~1750
1550~1600
1552
4230
2930
3020
3180

1630
1490
2730
2530
2330
2330
2630
2130
1530
1930
2750
3030
2315
1950
2500
2270

2350
2050
2350
2387
2340
2360
2355
2400
2346
2400

2680
56.8
75.3
68.0
64.3

88.0
81.3
140.5

56.0
87.0
107.0
79.0
27.0
79.0

0.00
2.56
3.62
3.68
2.83
1.55~1.65
3.40~3.50
7.94
9.7
10.6
10.6
9.6
7.6
4.5
0.00

8.9
0.7
11.2
46

5500
4600
46000
44
1100
64
166
118
36
108
13
1.27

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Discovery and early history of rare earth https://www.joysine.com/discovery-and-early-history-of-rare-earth/ Mon, 16 Oct 2017 14:24:54 +0000 https://www.joysine.com/?p=947 Rare earth elements became known to the world with the discovery of the black mineral “ytterbite” (renamed to gadolinite in 1800) by Lieutenant Carl Axel Arrhenius in 1787, at a quarry in the village of Ytterby, Sweden.

Arrhenius’ “ytterbite” reached Johan Gadolin, a Royal Academy of Turku professor, and his analysis yielded an unknown oxide (earth) which he called yttria. Anders Gustav Ekeberg isolated beryllium from the gadolinite but failed to recognize other elements which the ore contained. After this discovery in 1794 a mineral from Bastnäs near Riddarhyttan, Sweden, which was believed to be an iron-tungsten mineral, was re-examined by Jöns Jacob Berzelius and Wilhelm Hisinger. In 1803 they obtained a white oxide and called it ceria. Martin Heinrich Klaproth independently discovered the same oxide and called it ochroia.Discovery and early history of rare earth

Thus by 1803 there were two known rare earth elements, yttrium and cerium, although it took another 30 years for researchers to determine that other elements were contained in the two ores ceria and yttria (the similarity of the rare earth metals’ chemical properties made their separation difficult).

In 1839 Carl Gustav Mosander, an assistant of Berzelius, separated ceria by heating the nitrate and dissolving the product in nitric acid. He called the oxide of the soluble salt lanthana. It took him three more years to separate the lanthana further into didymia and pure lanthana. Didymia, although not further separable by Mosander’s techniques was a mixture of oxides.

In 1842 Mosander also separated the yttria into three oxides: pure yttria, terbia and erbia (all the names are derived from the town name “Ytterby”). The earth giving pink salts he called terbium; the one which yielded yellow peroxide he called erbium.

So in 1842 the number of rare earth elements had reached six: yttrium, cerium, lanthanum, didymium, erbium and terbium.

Nils Johan Berlin and Marc Delafontaine tried also to separate the crude yttria and found the same substances that Mosander obtained, but Berlin named (1860) the substance giving pink salts erbium and Delafontaine named the substance with the yellow peroxide terbium. This confusion led to several false claims of new elements, such as the mosandrium of J. Lawrence Smith, or the philippium and decipium of Delafontaine.

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Cerium Sulfate Tetrahydrate https://www.joysine.com/cerium-sulfate-tetrahydrate/ Mon, 16 Oct 2017 13:41:58 +0000 https://www.joysine.com/?p=945
CAS NO : 10294-42-5
Mol Fm : Ce(SO4)2·4H2O
Prop. : Yellow crystalline powder, soluble in water and alcohol;Hydroscopic
Packing : Drum inner with plastic bag. Net weight 25/50 kg
Storage : Keep sealed and store in dry and cool places
Apps : As oxidizing agent,water-proofing agent and antifungal agent

CODE CESO-4N CESO-3N CESO-2N
TREO>% 42 42 42
CeO2/REO>% 99.99 99.9 99.0
Water-insoluble<% 0.05 0.05 0.1
Non-rare earth impurities<ppm
Fe2O3 10 10 20
CaO 10 50 100
SiO2 20 50 100
PbO 10 50 100
Cl- 100 200 200
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