Aluminium fluoride hydrate

Figure 2.12 X-ray diffraction pattern of the aluminium fluoride hydrate obtained after microwave irradiation atT— 140°C. Inset effect of the temperature on the XRD...

In the second part (Section 5.3), the strong potential of these techniques for the study of functionalized Al-based inorganic fluorides, synthesized for their possible application as catalysts (fluorinated alumina and zeolites, high surface area aluminium trifluorides and nanostructured aluminium fluoride hydrates and hydroxyfluorides), is shown. The compounds used as model for the assignment of the V and Al NMR lines in these materials are also presented. 

Another way to increase resolution while avoiding an excessively long experimental time is to constmct a two-dimensional one pulse (TOP) spectrum [21-23] from a conventional ID MAS spectrum. The TOP spectmm evidences the well-known narrowing of the inner satellite transition line width when the components are not well resolved on the N = 0 cross-section, the projection over the satelhte transitions (N 0) shows a much better resolution as shown in HS pyrochlore aluminium hydroxyfluoride [20] (Figure 5.6), nanostructured Al-based fluoride-oxide materials [24] and aluminium fluoride hydrate with cationic vacancies [25]. 

Nanostructured Aluminium Hydroxyfluorides and Aluminium Fluoride Hydrate with Cationic Vacancies... 

Aluminium fluoride (anhydrous) [7784-18-4] M 84.0, m 250°. Technical material may contain up to 15% alumina, with minor impurities such as aluminium sulfate, cryolite, silica and iron oxide. Reagent grade AIF3 (hydrated) contains only traces of impurities but its water content is very variable (may be up to 40%). It can be dried by calcining at 600-800° in a stream of dry air (some hydrolysis occurs), followed by vacuum distn at low pressure in a graphite system, heated to approximately 925° (condenser at 900°) [Henry and Dreisbach J Am Chem Soc 81 5274 1959]. 

Aluminium potassium sulfate dodecahydrate Aluminium sulfate hydrate <30% aq. sol n Ammonium acetate sat d aq. sol n Ammonium bicarbonate Ammonium carbonate sat d aq sol n Ammonium chloride sat d aq. sol n Ammonium fluoride 30-70% aq. sol n Ammonium hydrogen fluoride Ammonium nitrate Arsenic trichloride Cadmium oxide solid Calcium chloride 30-70% sat d aq. sol n Cobalt sulfate heptahydrate... 

Soluble forms of aluminium present in waters are the simple hydrated Al " " cation, cationic and anionic hydroxo complexes, sulphate complexes of [AISO4] and A1[(S04)2], and following fluoridation it also occurs as fluo-roaJuminates with 1-6 coordinated atoms of fluorine, for example [AlFg]. ... 

Some aluminium foundries melt material recovered from the electrolysis of aluminium. In this instance, inorganic pollutants such as hydrogen fluoride may be formed. These ean be eleaned from the flue-gas using a chemisorption step, which can be added onto the dust abatement system. In this treatment calcium hydrate or aluminium oxide ean be used as the adsorbant. 

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