Aluminum chloride, dissolution

Aryl halides show much the same response to characterization tests as the hydrocarbons from which they are derived insolubility in cold concentrated sulfuric acid inertness toward bromine in carbon tetrachloride and toward permanganate solutions formation of orange to red colors when treated with chloroform and aluminum chloride dissolution in cold fuming sulfuric acid, but at a slower rate than that of benzene. 

The Alcoa (Aluminum Company of America) process involves the electrolysis of aluminum chloride which is carried out in a molten bath of the composition 50% sodium chloride, 45% lithium chloride and 5% aluminum chloride, maintained at 700 °C. The Bayer process, which involves the production of pure alumina by the dissolution of bauxite with caustic soda and which has been described in the chapter on hydrometallurgy, must be taken into account while presenting a complete picture of the aluminum extraction flowsheet. It... 

To a flame-dried, three-neck, 1-1 flask were added, in order, p-xylene (107 g, 1.0 mol), phosphorus trichloride (412 g, 3.0 mol), and anhydrous aluminum chloride (160 g, 1.2 mol). The reaction mixture was slowly heated to reflux with stirring. After 2.5 h at reflux, the reaction was allowed to cool to room temperature and the volatile components distilled at reduced pressure. The residual oil was slowly added to cold water (1 1) with stirring, and a white solid formed. The solid was removed by filtration, washed with water, and air dried. The solid was suspended in water (1 1) to which was added 50% sodium hydroxide solution (90 ml) to cause dissolution. The solution was saturated with carbon dioxide and filtered through Celite . The basic solution was washed with methylene chloride (200 ml) and acidified with concentrated hydrochloric acid (200 ml). The white solid that separated was isolated by extraction with methylene chloride (3 x 250 ml). The extracts were dried over magnesium sulfate, filtered, and evaporated under reduced pressure to give the pure 2,5-dimethylbenzenephosphinic acid (99 g, 60%) as an oil, which slowly crystallized to a solid of mp 77-79°C. 

Excision reactions are sometimes accompanied by redox chemistry. For example, dissolution of the 2D solid Na4Zr6BeCli6 in acetonitrile in the presence of an alkylammonium chloride salt results in simultaneous reduction of the cluster cores (144). Here, the oxidation product remains unidentified, but is presumably the solvent itself. As a means of preventing such redox activity, Hughbanks (6) developed the use of some room temperature molten salts as excision media, specifically with application to centered zirconium-halide cluster phases. A number of these solids have been shown to dissolve in l-ethyl-2-methylimidazolium chloride-aluminum chloride ionic liquids, providing an efficient route to molecular clusters with a full compliments of terminal chloride ligands. Such molten salts are also well suited for electrochemical studies. 

Several electrolyte compositions were suggested, but it appears that the simple LiCl-NaCl system is the best choice. Aluminum chloride, which is readily soluble in alkali halide salts, is a covalent compound, but it is ionized upon dissolution, forming anionic complexes like AlClf [257] (See Section IV. A. 1). 

Aluminum chloride, which was obtained from Fluka Chemical Corporation, generates heat during dissolution. 

Dissolution of Solids by Forming Complexes. If one takes an aluminum chloride solution and adds sodium hydroxide solution, two observations can be made. Using only a little amount of hydroxide solution, a precipitation occurs (see E9.11) ... 

Typical procedure. Symmetrical diaryl ketone [946] In a 100-mL round-bottomed flask with a side-arm, oxalyl chloride (1.05 mL, 12 mmol) was added dropwise over a period of 5 min to a solution of p-xylene (1.23 mL, 10 mmol) in dichloromethane (50 mL) at 5 °C. Aluminum chloride (1.33 g, 10 mmol) was then added portion-wise over 5 min to give a yellow suspension. The reaction mixture was allowed to warm to room temperature and stirred for 1 h, during which time dissolution of the solid and gas evolution were observed. A second equivalent of p-xylene (1.23 mL, 10 mmol) was then added dropwise over a period of 5 min, and the reaction mixture was stirred for 13 h at room temperature. It was then chilled in an ice/ water bath, and water (25 mL) was added dropwise over a period of 10 min. The layers were separated, and the aqueous layer was extracted twice with dichloro-... 

For example, chloride and duoride ions, even in trace amounts (ppm), could cause the dissolution of aluminum metallization of complimentary metal oxide semiconductor (CMOS) devices. CMOS is likely to be the trend of VLSI technology and sodium chloride is a common contaminant. The protection of these devices from the effects of these mobile ions is an absolute requirement. The use of an ultrahigh purity encapsulant to encapsulate the passivated IC is the answer to some mobile ion contaminant problems. 

In order to understand the general behavior of the tested materials, scoping tests were conducted in 25 mg/L gold(III)-chloride solutions at 25°C and 80°C with different initial pH values, namely 1.5, 4 and 8. After the start of the experiment the pH was not further adjusted, i.e., it could change freely. It remained similar to the initial pH in all cases. From these tests it was found that, in the case of the iron-oxide based adsorbents, dissolution of the solid took place at pHaluminum oxides and titanium oxide was observed at this pH. At pH>2 all adsorbents were found to be stable and did not dissolve during the experiment. 

The process sequence currently used for waste salts (except those containing aluminum for which no process currently exists) is shown in Figure 1. The process includes (1) dilute hydrochloric acid dissolution of residues (2) cation exchange to convert from the chloride to the nitrate system and to remove gross amounts of monovalent impurities (3) anion exchange separation of plutonium (4) oxalate precipitation of americium and (5) calcination of the oxalate at 600°C to yield americium oxide. 

The processes that take place in the pit and in its vicinity are shown in Fig. 20M(a). At the concentration of chloride ions found in seawater, the passive layer on aluminum breaks down, and anodic dissolution of the metal can occur. This happens mostly inside the pit, where the supply of oxygen is slow. On the other hand, oxygen reduction can readily take place on the surface of the metal outside the pits, where its diffusion path is short. Thus, the cathodic area is typically... 

The viscosity of caramel allows its employment as an adhesive and binder for instant sand-molds and foundry core for producing difiicultly accessible, hollow cavities in castings. Caramel binds together a sodium chloride, quartz, or metal-powder matrix to a mass that binds to aluminum or aluminum-alloy castings. On casting, such a binder produces only a small volume of combustion gases. The cores are readily removed, either mechanically or by dissolution. ... 

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