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Properties of the Elements and Inorganic Compounds
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
1360 Iron(II) phosphate octahydrate 1329 Iron phosphide (FeP) 1330 Iron phosphide (Fe2P) 1331 Iron phosphide (Fe3P) 1397 Iron(III) pyrophosphate nonahydrate 1361 Iron(II) selenide 1333 Iron silicide 1399 Iron(III) sodium pyrophosphate 1362 Iron(II) sulfate 1400 Iron(III) sulfate 1364 Iron(II) sulfate heptahydrate 1363 Iron(II) sulfate monohydrate 1401 Iron(III) sulfate nonahydrate 1365 Iron(II) sulfide 1366 Iron(II) tantalate 1367 Iron(II) tartrate 1368 Iron(II) telluride 1402 Iron(III) thiocyanate 1369 Iron(II) thiocyanate trihydrate Iron(II) titanate Iron(II) tungstate Krypton Krypton difluoride Krypton fluoride hexafluoroantimonate 1406 Lanthanum 1407 Lanthanum aluminum oxide 1408 Lanthanum boride 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1428 1420 1421 1422 Lanthanum bromate nonahydrate Lanthanum bromide Lanthanum carbide Lanthanum carbonate octahydrate Lanthanum chloride Lanthanum chloride heptahydrate Lanthanum fluoride Lanthanum hydride Lanthanum hydroxide Lanthanum iodate Lanthanum iodide Lanthanum monosulfide Lanthanum nitrate hexahydrate Lanthanum nitride Lanthanum oxide 1370 1371 1403 1404 1405
Determination of Metals in Soils
Published in T. R. Crompton, Determination of Metals and Anions in Soils, Sediments and Sludges, 2020
Although the method is not subject to interference from most constituents of soils, small traces of copper inhibit the release of hydrogen selenide so the selenium is separated by co-precipitation with lanthanum hydroxide. Treatment of the sample with hot oxidising acids at a controlled temperature is still required, but need not be prolonged as trace amounts of unoxidised organic matter do not interfere as they do in the fluorometric method. In the final solution selenium must be present as selenium(IV), as the efficiency of the sodium tetrahydroborate(III) reduction depends on the oxidation state. This is achieved by adding 4% of potassium bromide to the final solution and heating at 50°C.
Medical Applications
Published in Suresh C. Ameta, Rakshit Ameta, Garima Ameta, Sonochemistry, 2018
Electron microscopy was used to follow the permeation of an electron-dense, colloidal tracer, that is lanthanum hydroxide (LH). Experiments have been carried out on using the hairless guinea pig. Colloidal LH suspensions were put on different skin locations, which were then immediately exposed to ultrasound having range at 10-16 MHz, for duration of 5-20 min. It was observed that LH penetrates the skin through the stratum corneum (SC) under ultrasound exposure and LH passed through the epidermis to the upper dermis, even after only 5 min of ultrasound exposure.
Conceptual Process Development for the Separation of Thorium, Uranium, and Rare Earths from Coarse Coal Refuse
Published in Mineral Processing and Extractive Metallurgy Review, 2023
Deniz Talan, Qingqing Huang, Liang Liang, Xueyan Song
The species distribution diagrams of selected rare earth elements are shown in Figure 3. Five rare earth elements (i.e. cerium, neodymium, gadolinium, lanthanum, and yttrium) were selected based on their dominant concentrations in the feedstock solution and to represent different rare earth groups (i.e. heavy, light, critical, and uncritical rare earth elements). It is known that most rare earth elements existed in the synthetic solution as REEs3+. However, they may also have divalent or tetravalent states, but these states of rare earths are not stable (Thakur 2000). Rare earths become less soluble with increasing pH, and thermodynamically stable rare earth hydroxides can be obtained by treating aqueous solutions with a basic chemical reagent. Rare earths’ resistance to the base and solubility decreases from light rare earths toward heavy rare earths, with lanthanum being the most alkali and soluble, having the highest solubility constant. Table 1 confirms that lanthanum hydroxide has a solubility constant (log K) of 20.29. It is then followed by cerium, neodymium, yttrium, and gadolinium with solubility products (log K) of 19.89, 18.09, 17.49, and 15.09, separately (Table 1). On the other hand, cerium (IV) and scandium exhibit the opposite behavior (Stevenson and Nervik 1961). The species distribution diagrams of lanthanum and cerium (Figures 2A1 and D) support the above statement.
Fluoride removal from water using alumina and aluminum-based composites: A comprehensive review of progress
Published in Critical Reviews in Environmental Science and Technology, 2021
Sikpaam Issaka Alhassan, Lei Huang, Yingjie He, Lvji Yan, Bichao Wu, Haiying Wang
Extensive research has been conducted on the defluorination capacity of some rare earth metals such as Lanthanum. Shi et al. (2013) investigated an equimolar mixture of Lanthanum oxide impregnated granular activated alumina (LAA) for the removal of fluoride ions in water. Lanthanum impregnation on alumina was repeated 5 times and further calcined at a temperature of 573 K. The study pointed out that, the calcination resulted in about a 19.1% increase in the content of Lanthanum and was also responsible for the optimum fluoride adsorption of 16.9 mg·g−1. The study again observed that Lanthanum oxide impregnated granular activated alumina adsorbed 70.5–77.2% fluoride in the pH range of 3.9–9.6 higher than Puri and Balani (2000) compared the fluoride removal capacity of two adsorbents thus, alumina impregnated with Lanthanum hydroxide and original alumina. The adsorption capacity of the original alumina was 0.170–0.190 mM·g−1. Whereas the adsorption capacity of the alumina impregnated with lanthanum hydroxide was found to be 0.340–0.365 mM·g−1. Fluoride adsorption was significantly affected by the presence of phosphate and sulfate ions whereas ions such as chloride, bromide, iodide and nitrate did not significantly influence the adsorption of fluoride onto the adsorbent (Teutli-Sequeira et al., 2014). Maximum adsorption of fluoride occurred at a pH range of 5.7–8.0 and was more effective when fluoride concentration decreased from 7 to 0.003 nM and the adsorption process followed the Langmuir model.
Rare-earth metal based adsorbents for effective removal of arsenic from water: A critical review
Published in Critical Reviews in Environmental Science and Technology, 2018
Yang Yu, Ling Yu, Kok Yuen Koh, Chenghong Wang, J. Paul Chen
Lanthanum is one of the lest expensive and most abundant rare-earth elements and can be obtained from bastnesite and monazite (Sen & Peucker-Ehrenbrink, 2012). The performance of lanthanum compounds, including lanthanum hydroxide (La(OH)3), lanthanum carbonate (La2(CO3)3), and basic lanthanum carbonate (La(OH)CO3), on the As(V) removal was first studied by Tokunaga, Wasay, & Park, (1997). The adsorption mechanism was suggested to be the ion exchange between the functional groups (e.g., CO3 and OH) with As(V) ions in the neutral to alkaline pH range as described in Eqs. (1–3) and the formation of insoluble lanthanum arsenate (LaAsO4) in the acidic pH range as expressed in Eq. (4).