Aluminium production data

Fig. 13.2 Production of aluminium in the US between 1955 and 2004. The contribution that recycled aluminium has made to the market became increasingly important in the latter part of the twentieth century and has now overtaken primary production. [Data US Geological Survey.]...

The data given in Tables 1.9 and 1.10 have been based on the assumption that metal cations are the sole species formed, but at higher pH values oxides, hydrated oxides or hydroxides may be formed, and the relevant half reactions will be of the form shown in equations 2(a) and 2(b) (Table 1.7). In these circumstances the a + will be governed by the solubility product of the solid compound and the pH of the solution. At higher pH values the solid compound may become unstable with respect to metal anions (equations 3(a) and 3(b), Table 1.7), and metals like aluminium, zinc, tin and lead, which form amphoteric oxides, corrode in alkaline solutions. It is evident, therefore, that the equilibrium between a metal and an aqueous solution is far more complex than that illustrated in Tables 1.9 and 1.10. Nevertheless, as will be discussed subsequently, a similar thermodynamic approach is possible. 

Most acids are corrosive to aluminium-base materials. The oxidising action of nitric acid at concentrations above about 80%, however, causes passivation of aluminium. Very dilute and very concentrated sulphuric acid dissolves aluminium only slowly. Figures 4.4 and 4.5 give corrosion data at various concentrations for these two acids. The corrosion rates of aluminium in other inorganic acids in dilute solution are shown in Fig. 4.6. Boric acid also exerts little attack on aluminium, while a mixture of chromic and phosphoric acids can be used for the quantitative removal of corrosion products from aluminium without attacking the metal. 

The most valuable and comprehensive kinetic studies of alkylation have been carried out by Brown et al. The first of these studies concerned benzylation of aromatics with 3,4-dichloro- and 4-nitro-benzyl chlorides (these being chosen to give convenient reaction rates) with catalysis by aluminium chloride in nitrobenzene solvent340. Reactions were complicated by dialkylation which was especially troublesome at low aromatic concentrations, but it proved possible to obtain approximately third-order kinetics, the process being first-order in halide and catalyst and roughly first-order in aromatic this is shown by the data relating to alkylation of benzene given in Table 77, where the first-order rate coefficients k1 are calculated with respect to the concentration of alkyl chloride and the second-order coefficients k2 are calculated with respect to the products of the... 

According to data [10,11], practically monophase anorthite can be synthesized after mechanical treatment of a mixture of calcium oxide with aluminium hydroxide and hydrated silica followed by thermal treatment at 1000°C for 4 h. Fig. 7.3 shows X-ray pattern of this mixture. After activation for 5 min (Fig. 7.3, curve 1), the reaction mixture exhibits a small amount of individual crystal calcium oxide (0.240 nm) and aluminium hydroxide (0.482, 0.436, 0.245 nm), while the major part of CaO is bound into an X-ray amorphous product. The annealing of the activated mixture at 1000°C gives anorthite (Fig. 7.3, curve 3) while the thermal treatment of non-activated mixture brings to the formation of intermediate product, wollastonite (Fig. 7.3, curve 2). The lines of this product are absent in X-ray patterns of the activated mixture. 

The nature of the cocatalyst in the Ziegler-Natta systems exerts a significant effect on the polymerization rate and isotacticity of the polymer product Interesting data were obtained by Keii et al. when the cocatalyst was changed during polymerization. The pronounced effect of the cocatalyst is the basis of the concept on the bimetallic composition of ACg according to which the latter are represented, for example, as binuclear complexes including titanium and aluminium. 

Huston s work [997] also indicated that the reaction between aluminium(III) chloride and COCIj resulted in the formation of the 1 1 adduct, AlCIg.COClj, which readily loses phosgene in vacuo at room temperature to yield pure aluminium(III) chloride. This was later confirmed independently by tensimetric titration (see Fig. 9.5) [376], and the i.r. spectrum (see Table 9.1) of the white product (m.pt. 25 C dissociation pressures of 4.8 kPa at 0 C and 58.66 kPa at 25 C) indicated that the phosgene was O-bonded, viz. [Cl2C=0—>A1C13], and that no [A1C1 ] was present [376]. From the data in this paper, the enthalpy of dissociation of the adduct can be calculated ... 

The authors also prepared anhydrous aluminium selenate by heating AIH(Se04)2 H20 to 600 K. The product will be denoted as solid only, as a check of its crystalline state is not mentioned. The enthalpy of dissolution of the two aluminium selenates in 0.5 M KOH to the same unspecified concentration was measured to be - (178.90 + 0.92) kJ-mol and - (442.30 1.02) kJ-mof with the result for the anhydrous compound mentioned last. From these data the standard enthalpy of formation of Al2(Se04)3(s) is calculated to be-(2561.68 17.11) kJ-moP. ... 

From these data we can draw the following conclusions concerning the cost price. For the production of a ton of aluminium two tons of alumina are required and also one ton of carbon for the electrodes while, for the production of the alumina itself, six tons of carbon are required. Since alumina is made near the spot where bauxite is found, it is necessary to consider the effect of the following transport charges upon the cost price —... 

To 292 mg (1.3 mmol) of a mixture of 1.2.6d/1.2.6e (1 9) dissolved in ether 500 mg of aluminium oxide neutral was added and this heterogenous mixture was stirred for 2 h at room temperature. Filtration and rota-evaporation of the solvent gave an oily raw product which was crystallized at -20 °C from ether/hexane to yield 270 mg (93%) of pure 1.2.6d, mp 48 - 49 °C. All spectroscopic datas were identical with the sample obtained by chromatography of the photoproduct. 

Full details have appeared on the formation of the novel 4(5 6)u6eo-steroid system (374) which is produced in about 90% yield by prolonged treatment of 6) -bromo-4, 5 -epoxycholestan-3)S-ol with lithium aluminium hydride. The structure has been confirmed by independent synthesis " of the derivative (375) and the rearrangement has been shown ° to be, in essence, a 1,3-elimination of the initial lithium aluminium hydride reduction product (373), which can be isolated after brief treatment of the bromo-epoxide with hydride. On the basis of the spectral data, the preferred conformations of the seven-membered ring have been deduced. ... 

Ian Payne, Quest International - for organoleptical stability data of muguet ingredients Steven Rowlands, Quest International - for analysis of the breakdown products of Lilial in antiperspirant base Andy Roche, Reheis - for information on the partial hydrolysis of aluminium chlorohydrate. 

Baneijee et al.66 have developed an alternative synthesis of the compound (129) whose utility in synthesis of Mansonone F (120) has been reported by Suh and collaborators.65 This is described in Scheme 13. Tetralone (127) was reduced with sodium borohydride to alcohol which on alkylation with benzyl chloride produced benzyl derivative (132). Its conversion to (133) was attempted by treatment with boron tribromide in dichloromethane. C ompound (133) (characterized b y m ass s pectroscopy) was obtained in poor yield. The major product was the diol (134), whose structure was confirmed by spectral data. It indicates that the demethylation was accompanied by debenzylation. Treatment of diol (134) with triethyl orthoformate and aluminium chloride afforded aldehyde (135) which was subjected to catalytic hydrogenation to produce compound (136). It was transformed to ketone (137) by oxidation and then made to react with methylmagnesium bromide in ether. The resulting tertiary alcohol on heating with p-toluenesulfonic acid in toluene for 24 hr produced the naphthalene (129) in 78% yield. 

Zare and co-workers have used the technique of laser-induced fluorescence to obtain considerable data on the product AlO in the reaction of aluminium and oxygen [384], and BaO in the reactions of barium with oxygen and carbon dioxide [385]. 

A series of papers presents a detailed account of the hydrocyanation of ajS-unsaturated ketones with either (a) mixtures of trialkylaluminium, or an alkyl-aluminium halide, with HCN or h) a dialkylaluminium cyanide. Cholest-4-en-3-one gives the 5a- and 5 -cyano-3-ketones almost quantitatively. A A -ll-oxo-steroid gave the 8)3-cyano-l 1-ketone, despite being unreactive by older methods. Mechanistic features of these processes have been largely elucidated conditions can be chosen to give products of either kinetic or thermodynamic control. Kinetic data are analysed for hydrocyanation of cholest-4-en-3-one and b-norandrost-4-en-3-one. ... 

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