A comparative study of surface acidity in the amorphous, high surface area solids, aluminium fluoride, magnesium fluoride and magnesium fluoride containing iron(III) or aluminium(III) fluorides

Investigating acidity of metal fluoride surfaces by spectroscopic and chemical methods

“…In Sections 5, 6, 7, and 8 the dehydrochlorination of tert-butyl chloride, which occurs at room temperature in the presence of fluorinated Lewis acid surfaces, is emphasised. Accounts of the various hydrochlorocarbon-solid Lewis acid catalyst systems that are precursors to the use of Bu t Cl as a Lewis acid probe and descriptions of experimental details of the radiotracer method used are available elsewhere [13,15,16].…”

“…An identical conclusion is reached from consideration of room temperature dehydrochlorination of Bu t Cl in the presence of the two compounds. Exposure of HS-AlF 3 to Bu t Cl vapour at room temperature results in the immediate observation of HCl above the surface [16]; in contrast evolution of HCl when b-AlF 3 is exposed to Bu t Cl under identical conditions is a slow process [33]. The use of [ 36 Cl]-Bu t Cl enables interactions with the surface to be probed [16]; the behaviour observed in experiments that involve H 36 Cl or [ 36 Cl]-Bu t Cl, although not unlike that found for analogous experiments with ACF (Fig.…”

“…The sample used in (b) had been fluorinated at the final step using aHF/N 2 at 393 K; its BET area was 420 m 2 g À1 [16]. The [ 36 Cl] specific count rate of the [ 36 Cl]-Bu t Cl used was identical in both experiments, therefore in (b), the higher surface counts and their greater precision can be assumed to be, at least partly, a reflection of the greater specific surface area.…”

Vapor phase hydrofluorination of acetylene to vinyl fluoride over La2O3-Al2O3 catalysts

“…Nano-sized AlF 3 is known to be one of the most effective solid Lewis acids [27][28][29][30]. In contrast, LaF 3 is slightly alkalescent.…”

Aluminum Fluoride‐Supported Platinum and Palladium as Highly Efficient Catalysts of n‐Pentane Hydroisomerization

“…[1] Those studies were motivated by recent knowledge concerning preparation of nanoscopic aluminum fluoride [2][3][4] characterized by highly specific surfaces, and, remarkably, by outstanding high surface acidity. [5,6] These interesting properties suggest potential applications of HS-AlF 3 in bifunctionally catalyzed reactions, such as hydroisomerization of n-alkanes. Strong acidity of aluminum fluoride has already been combined with hydrogenative properties of gold to create an example of bifunctional catalysts in the reaction of menthol synthesis.…”