CrCl3 Chromium chloride

The electrodeposition of chromium in a mixture of choline chloride and chromium(III) chloride hexahydrate has been reported recently [39]. A dark green, viscous liquid is obtained by mixing choline chloride with chromium(III) chloride hexahydrate and the physical properties of this deep eutectic solvent are characteristic of an ionic liquid. The eutectic composition is found to be 1 2 choline chloride/chromium chloride. From this ionic liquid chromium can be electrode-posited efficiently to yield a crack-free deposit [39]. Addition of LiCl to the choline chloride-CrCl3-6H20 liquid was found to allow the deposition of nanocrystalline black chromium films [40], The use of this ionic liquid might offer an environmentally friendly process for electrodeposition of chromium instead of the current chromic acid-based baths. However, some efforts are still necessary to get shining... 

We have considered ceramic synthesis in an open crucible and closed glass tube. A third possibility is a flow system. Chromium chloride, CrCl3, can be prepared by passing carbon tetrachloride over a sample of chromium oxide maintained at 900°C (Angelici, 1986) ... 

C4H80-CrCl3 Chromium (III) chloride-tris (tetrahy drofuran), 8 150... 

A solution of 26.8 g. of green chromium chloride hydrate [CrCl3(1130)4] Cl 2 H3O in an equal amount of water Is allowed to stand for 24 hours at room temperature, and a mixture of 10 g. of cone. H3SO4 and 4 g. of water is then added. The sulfate soon separates in bright green tablets. 

Green, crystalline chromium chloride hydrate [CrCl3(H30) 4] Cl 2 HgO and somewhat more than the stoichiometric quantity of urea are dissolved in some water and treated with a few drops of HCl. The solution is concentrated in a drying oven at 75 °C (or on the steam bath) until a crystalline crust forms. The crystal slurry thus obtained is dissolved in the minimum quantity of water at 50-60°C and rapidly filtered. The salt complex separates as green needles. 

Green chromium chloride hydrate [CrCl3(OHg)4]Cl 2 HgO is converted into [CrCl3(OHg)4]Cl on standing for 3 days in a vacuum desiccator over cone. H3SO4. It is then suspended In absolute ether [CrCl3(OHa)3] is formed by disproportionation and dissolves with a brown-violet color. On evaporation of the ethereal solution in the absence of atmospheric moisture, [CrCl3(OH3)3] is obtained as an amorphous brown powder. 

Halides chromium chloride (CrCl3) chromium(III) chloride hexahydrate ([Cr OH2 6]Cl3). 

These have been known for many years.1052-1054 Chromium(III) is approximately octahedral ( ie(f = 3.69-4.1 BM) the compounds have a layer structure. In the chloride, r(Cr—Cl) is 5.76 A between layers and 3.46 A within layers. The iodide is isomorphous with the chloride and the bromide has a similar but distinct structure. All may be prepared by the direct halogenation of the metal. Other methods are available, e.g. CrCl3 may be prepared by heating Cr203-xH20 in CCU vapour at 650 °C.1055 The anhydrous halides are insoluble in water, however reducing agents such as zinc catalyze dissolution. The trichloride reacts with liquid ammonia to form ammine complexes. 

Hydrate isomers are a special type of ionization isomer. They differ by an exchange between an HzO molecule and another ligand in the coordination sphere (Fig. 16.24). For example, the solid hexahydrate of chromium(III) chloride, CrCl3-6H20, may be any of the three compounds... 

In contrast, Kim et al. (13) found that the amount of aluminum removed from the zeolite lattice during ion-exchange with solutions of metal chlorides was directly related to the pH of the solution and that the presence of the metal cation played no part in the dealumination. Our work more closely mirrors that of Bailar and coworkers (14-16) who found that solutions of CrCl3 under reflux conditions could dealuminate a variety of zeolites to a much greater extent than the pH of the CrCl3 solutions would predict. To explain their results, they proposed that the chromium cations could complex with hydrolyzed aluminum ions in the zeolite through the formation of "ol bridges" which then diffused out of the zeolite. Therefore,... 

Reaction of chromium(III) ions To study these reactions use a 0 33m solution of chromium(III) chloride CrCl3,6H20 or a 0166m solution of chromium(III) sulphate Cr2(S04)3.15H20. 

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