Lanthanum salts preparation

Lanthanum chloride is used to prepare other lanthanum salts. The anhydrous chloride is employed to produce lanthanum metal. 

Lanthanum hydroxide is used to prepare other lanthanum salts. 

The nitrate is used as an analytical standard as a matrix modifier in furnace AA analysis and for preparing other lanthanum salts. 

In recent years, the application of lanthanide-containing composites as the catalysts or catalyst promoters for the organic synthesis has attracted much attention. They can increase the activity and selectivity for many reactions. The application of lanthanum salt in the field of catalysis has emerged. The preparation methods for the supported lanthanum salt are similar to that of the supported lanthanum oxides, herein we don t repeat again. 

The supported lanthanum salt is used in many catalytic reactions. X. Yang and L. Suo synthesized n-butyl acetate using the active carbon supported lanthanum sulfate as the catalyst. The ester yield could reach 97.5% and the quality of the product was quite good. The high activity of catalyst can be easily recovered [248]. W-butyl acetate is an important organic chemical. In industrial preparation process, the -butyl acetate is derived from the... 

The rare earth oxides of lanthanum, samarium and gadolinium were converted into soluble nitrate salts by dissolving them in the minimum amount of concentrated nitric acid. Then two sets were prepared by adding 2.0 ml of aqueous solution of La(N03)3.6H20 [0.2 M] and 0.01 ml of (n-BuO)4Ti to 25 ml of aqueous solution of Cu(N03)2 [1.0 M]. Similarly, two sets were prepared with Co(N03)3. Same procedures were followed for Sm(N03)3 [0.2 M] and Gd(N03)3 [0.2 M], One set of all these solutions were sonicated under ultrasonic bath (Model - Meltronics, 20 kHz, 250 W) for half an hour. The solutions prepared in normal and sonicated conditions were kept in muffle furnace (Model - Deluxe Zenith) first at 100°C for 2 h and then the temperature of the furnace was raised up to 900°C and calcined for 2 h. The solid composites prepared were then cooled to room temperature and treated as catalyst for phenol degradation. 

The salt is prepared by dissolution of lanthanum oxide, hydroxide or carbonate in nitric acid, followed by crystallization, and obtained as a hexahydrate. The general reactions are as follows ... 

Lanthanum oxide can be produced by direct combustion of lanthanum in oxygen or air. The oxide also may be prepared by decomposition of an oxo salt of lanthanum, such as nitrate, sulfate, carbonate, hydroxide or oxalate. 

In spite of the potential basic properties of the Au(CN)2 anion, these complexes were not obtained in an acid-base reaction with silver salts. Instead, they were prepared by slow crystallization of pure gold and silver dicyanide complexes in different molar ratios (x = 0.25, 0.50, 0.75, 0.90). In the case of the two lanthanum derivatives, the exact compositions established by X-ray diffraction studies gave empirical formula in which x = 0.33 and 0.78. For the europium complexes, only one structural determination was performed with x= 0.14. 

Lanthanum Triazide, La(Ns)j, mw 222.97, N37-25 S, Curtius and Darapsky prepd the basic salt, Lanthanum Hydroxyazide, La (OH)(NjVl%HaO, by boiling a soln of lanthanum nitrate and sodium azide. The white slimy mass of basic lanthanum azide was obtained either on evapg the mixed soln in vacuo or on treating it with a mixt of ale eth. No props of the product were reported nor were there any addnt refs found in which any attempts were made to prepare and isolate the lanthanum azide... 

Mischmetal is produced commercially by electrolysis, The usual starting ingredient is the dehydrated rare earth chloride produced from monazite or bastnasite. The mixed rare earth chloride is fused in an iron, graphite, or ceramic crucible with the aid of electrolyte mixtures made up of potassium, barium, sodium, or calcium chlorides. Carbon anodes are immersed in the molten salt. As direct current flows through the cell, molten mischmetal huilcls up in the bottom of the crucible. This method is also used to prepare lanthanum and cerium metals. 

T. Curtius and A. Darapsky prepared a basic salt, lanthanum hydroxyazide, La(0H)(N3)2l H20, by boiling a soln. of lanthanum nitrate and sodium azide. The white, slimy mass of basic lanthanum azide is obtained by evaporating the mixed soln. in vacuo, or by treatment of the soln. with a mixture of alcohol and ether. They also made rose-coloured didymium hydroxyazide, Dy(OH)(N3)2, by evaporating a soln. of didymium carbonate in hydrazoic acid. Freshly precipitated yttrium hydroxide dissolves in hydrazoic acid, forming a soluble yttrium hydroxyazide boiling a soln. of yttrium sulphate and sodium azide gives a precipitate of yttrium hydroxide. L. M. Dennis found that zirconium hydroxide is precipitated when a soln. of zirconium salt is treated with potassium azide. 

Sengupta, S. K. et al., Transition Met. Chem., 2000, 25(2), 150 Three to one lanthanum and praseodymium salts were prepared. They exploded on heating above 180 C, making thermal studies difficult. Analogues without the nitro-group decompose controllably. 

The ternary systems display a variety of structural chemistry depending on the sizes of the alkaline and lanthanide metals (Scheme 3 Fig. 3 [43, 45-57]). The smaller alkali cations determine the expected coordination structures as found in salt-like compounds, e.g., Na3Y (NH2)6 or KY(NH2)4. Layer structures are observed in alkali metal poor systems like MLa2(NH2)7 while cesium derivatives, apart from the lanthanum compounds, form perowskit-like arrangements as in CsEu(NH2)3 and Cs3Ln2(NH2)9. The mono ammoniates of some Cs-systems are probably metastable. Preparation of analogous ternary systems with Li were unsuccessful in contrast to, e.g., LiAl(NH2)4 [58]. 

An interesting class of homoleptic lanthanide complexes has become available through the use of heteroallylic diphosphinomethanide ligands. The first member of the series was the lanthanum derivative, [CH(PPh2)2]3La (59c), which was characterized by X-ray crystallography (Fig. 19) [74]. The preparation of 59c involved treatment of anhydrous lanthanum trichloride with the potassium salt of the ligand ... 

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