Yttria earths

A first crude separation of the ceria earths from the yttria earths is achieved by adding solid oxalic acid to the filtrate from the double sulfate precipitation. Use of a saturated solution of oxalic acid yields a precipitate which is difficult to filter and necessitates further dilution of the solution. 

Gadolinite is an yttria earth-beryllium-iron (II) silicate its approximate composition is YsBesFeSisOio, and it contains up to 50% rare earth oxides and about 10% BeO. 

As a rule, yttrium (Y) is included in the rare earth group. While its electron configuration differs from that of lanthanides, the volume contraction of the latter with increase in their atomic weight justifies inclusion of Y, the atoms of which are very similar in density and volume to those of the lanthanide series. This similarity is also reflected in nature, where REE and Y coexist in many minerals. In fact, rare earths are frequently referred to as yttria earths . 

His theory of combustion, his researches on heat, and his discovery of the yttria earths in a mineral afterwards called gadolinite, are his best-known contributions to science. He taught the antiphlogistic theory from 1789, and his small text-book was the first in Swedish to teach the new system and did much to procure its adoption. He published an important dissertation on affinity. ... 

Ytterby, a village in Sweden near Vauxholm) Yttria, which is an earth containing yttrium, was discovered by Gadolin in 1794. Ytterby is the site of a quarry which yielded many unusual minerals containing rare earths and other elements. This small town, near Stockholm, bears the honor of giving names to erbium, terbium, and ytterbium as well as yttrium. 

In 1843 Mosander showed that yttira could be resolved into the oxides (or earths) of three elements. The name yttria was reserved for the most basic one the others were named erbia and terbia. 

From gadolinite, a mineral named for Gadolin, a Finnish chemist. The rare earth metal is obtained from the mineral gadolinite. Gadolinia, the oxide of gadolinium, was separated by Marignac in 1880 and Lecoq de Boisbaudran independently isolated it from Mosander s yttria in 1886. 

Another sol—gel abrasive, produced by seeding with a-ferric oxide or its precursors, has been patented (30). A magnesium-modified version of this abrasive, also called Cubitron, is being produced as a replacement for the earlier type. Yttria [1314-36-91-vnc>A V eA sol—gel abrasives have also been patented (31), as well as rare earth oxide modified materials (32). These abrasives are all produced by 3M Corporation they have performed very well ia various applications such as ia coated abrasives for grinding stainless steel and exotic alloys. 

Xenotime, like mona2ite, is a rare-earth phosphate. Up to 60% of its rare-earth content is yttria [1314-36-9], Xenotime has a higher... 

In 1794 the Finnish chemist J. Gadolin, while examining a mineral that had recently been discovered in a quarry at Ytterby, near Stockholm, isolated what he thought was a new oxide (or earth ) which A. G. Ekeberg in 1797 named yttria. In fact it was a mixture of a number of metal oxides from which yttrium oxide was separated by C. G. Mosander in 1843. This is actually part of the fascinating story of the rare earths to which we shall return in Chapter 30. The first sample of yttrium metal, albeit very impure, was obtained by F. Wohler in 1828 by the reduction of the trichloride by potassium. 

In 1751 the Swedish mineralogist, A. F. Cronstedt, discovered a heavy mineral from which in 1803 M. H. Klaproth in Germany and, independently, i. i. Berzelius and W. Hisinger in Sweden, isolated what was thought to be a new oxide (or earth ) which was named ceria after the recently discovered asteroid, Ceres. Between 1839 and 1843 this earth, and the previously isolated yttria (p. 944), were shown by the Swedish surgeon C. G. Mosander to be mixtures from which, by 1907, the oxides of Sc, Y, La and the thirteen lanthanides other than Pm were to be isolated. The small village of Ytterby near Stockholm is celebrated in the names of no less than four of these elements (Table 30.1). 

Ytter-erde, /. yttria (as class name) yttrium earth, -flussspat, m. yttrocerite, ytterhaltig, a. contammg yttrium, yttriferous, yttric. 

In both cases, we observe an amorphous pattern no crystallites of rare earth oxide appear even at 25% wt. loading. This indicates that oxide particles remain less than 30A in diameter. The surface area, pore volume and pore size distribution of the starting Si-Al support also change on impregnation. Table 1 lists the values for yttria-modified samples of... 

Mori M, Itoh H, Mori N, Abe T, Yamamoto O, Takeda Y, and Imanishi N. Reaction between alkaline earth metal doped lanthanum chromite and yttria stabilized zirconia In Badwal SPS, Bannister MJ, and Hannink RHJ. Science and Technology of Zirconia V. Lancaster, PA Technomic Publishing Co., 1993 776-785. 

Y-section rayon, 11 262, 263 Ytterbium (Yb), 14 631t, 635t electronic configuration, l 474t Yttria, 5 583, 14 630 Yttria-stabilized zirconia (YSZ), 26 637 Yttric rare earths (RE), 14 631 Yttrium(III)... 

Cerium was the first rare-earth element discovered, and its discovery came in 1803 by Jons Jakob Berzelius in Vienna. Johann Gadohn (1760—1852) also studied some minerals that were different from others known at that time. Because they were different from the common earth elements but were all very similar to each other, he named them rare-earth elements. However, he was unable to separate or identify them. In the 1800s only two rare-earths were known. At that time, they were known as yttria and ceria. Carl Gustav Mosander (1797—1858) and several other scientists attempted to separate the impurities in these two elements. In 1839 Mosander treated cerium nitrate with dilute nitric acid, which yielded a new rare-earth oxide he called lanthanum. Mosander is credited with its discovery. This caused a change in the periodic table because the separation produced two new elements. Mosander s method for separating rare-earths from a common mineral or from each other led other chemists to use... 

A stone quarry near the town of Ytterby in Sweden produces a large number of rare-earth elements. Carl Gustaf Mosander (1797-1858) discovered several rare-earths, including the rare-earth mineral gadolinite in this quarry in 1843. He was able to separate gadolinite into three separate, but closely related, rare-earth minerals that he named yttria (which was colorless), erbia (yellow color), and terbia (rose-colored). From these minerals, Mosander identified two new rare-earth elements, terbium and erbium. The terbia that was found was really a compound of terbium terbium oxide (Tb O )... 

In the 1800s chemists searched for new elements by fractionating the oxides of rare-earths. Carl Gustaf Mosander s experiments indicated that pure ceria ores were actually contaminated with oxides of lanthanum, a new element. Mosander also fractionated the oxides of yttria into two new elements, erbium and terbium. In 1878 J. Louis Soret (1827—1890) and Marc Delafontaine (1837-1911), through spectroscopic analysis, found evidence of the element holmium, but it was contaminated by the rare-earth dysprosia. Since they could not isolate it and were unable to separate holmium as a pure rare-earth, they did not receive credit for its discovery. 

Carl Gustaf Mosander, a Swedish chemist, successfully separated two rare-earths from a sample of lanthanum found in the mineral gadolinite. He then tried the same procedure with the rare-earth yttria. He was successful in separating this rare-earth into three separate rare-earths with similar names yttia, erbia, and terbia. For the next 50 years scientists confused these three elements because of their similar names and very similar chemical and physical properties. Erbia and terbia were switched around, and for some time the two rare-earths were mixed up. The confusion was settled ostensibly in 1877 when the chemistry profession had the final say in the matter. However, they also got it wrong. What we know today as erbium was originally terbium, and terbium was erbium. 

Gadolinum is found in minerals bastnasite and monazite, always associated with other rare earth metals. It was isolated from yttria in 1880 by the Swiss chemist Marignac, and discovered independently in 1885 by Boisbaudran. It was named in honor of the Swedish chemist Gadolin. Its abundance in the earth s crust is 6.2 mg/kg and concentration in sea water is 0.7 ng/L. 

The element was discovered in 1843 by Carl Gustav Mosander. He determined that the oxide, known as yttria, was actually a mixture of at least three rare earths which he named as yttria—a colorless oxide, erbia— a yellow oxide, and terbia— a rose-colored earth. Mosander separated these three oxides by fractional precipitation with ammonium hydroxide. Pure terbia was prepared by Urbain in 1905. The element was named terbium for its oxide, terbia, which was named after the Swedish town, Ytterby. 

The element was discovered in 1794 by the Swedish chemist Gadolin. He named it after the small town Ytterby in Sweden where the mineral containing yttria was found. Mosander in 1843 determined that the yttria consisted of three oxides yttria, erbia, and terbia. Yttrium occurs in all rare earths. It is recovered commercially from monazite sand, which contains about 3% yttrium. It also is found in bastnasite in smaller amounts of about 0.2%. Abundance of yttrium in earth s crust is estimated to be 33 mg/kg. The metal has been detected in moon rocks. 

J, J, Berzelius and his collaborator Wilheim Hisinger, isolated from a heavy mineral found in 1781 in a mine at Bastnas, Sweden, another similar and yet somewhat different "earth". This one was named ceria and the mineral cerite after the then recently discovered planetoid Ceres, It was believed at the time, that both yttria and ceria were single elements, but subsequent study showed each to be a mixture of oxides, the complete separation and identification of which required more than a century of effort. 

Ekeberg, A. G., Of the properties of the earth yttria, compared with those of... 

The mam object of Berzelius and Hisinger s analysis of cerite was to search for yttria, which might easily have escaped the attention of Scheele and de Elhuyar since it was unknown at the time their investigation was made (29). Although they failed to find yttria, Berzelius and Hisinger discovered instead the new earth ceria. ... 

Since yttria, as well as glucina, forms sweet salts, Klaproth preferred to call the latter earth berylha, and it is still known by that name. Beryl and the emerald are now known to be a beryllium aluminum silicate [Be3Al2(Si03)6]. 

XVich stores of the rare earth minerals lay hidden for centuries m the Scandinavian peninsula until, one day in 1787, Lieutenant Carl Axel Arrhenius found, near the Ytterby feldspar quarry in Roslagen, an unusual black rock which he at first called ytterite, but which was later named gadolinite for the famous Finnish scientist Johan Gadolin who detected in it yttria, scandia, and all the rare earths of the yttria group. 

Johan Gadolin, 1760-1852. Professor of chemistry at the University of Abo, Finland. Discoverer of the complex earth yttria, which afterward yielded an entire senes of simple oxides He made a thorough study of tire rare earth minerals from Ytterby, Sweden... 

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