Formation and structure of aluminium alkyl phosphates

Abstract

Aluminium alkyl phosphates (AlAPs) synthesized by the reaction of Al(NO 3 ) 3 ?9H 2 O with monohexyl, monooctyl or monodecyl phosphates in aqueous media have been characterized by various means. The XRD patterns of the AlAPs showed one strong and two weak diffraction peaks at 2hv15³. The plate-like AlAP particles prepared using octyl phosphate gave rise to lattice patterns having uniform alternating spacings of ca. 1.1 and 1.5 nm. When treated at 1000 ³C, AlAP samples were converted into tridymite AlPO 4 . The Al/P molar ratios of AlAP samples approximated to unity and their chemical formula can be written as (ROPO 3 )Al(OH)?1.2H 2 O. These facts suggest that the AlAPs are composed of alternating bimolecular layers of alkyl phosphates and a hydrated aluminium phosphate phase.

Formation and Structure of Titanium Alkyl Phosphates

“…The position of these peaks shifts to a lower diffraction angle and their intensities strengthen with elongating the carbon number of alkyl phosphates in a manner similar to that of CaAP and AlAP as reported previously (4,5). The detailed assignment of these peaks will be discussed later.…”

“…TiAP was prepared by the wet method under the same conditions as in the preparation of CaAP and AlAP (4,5). Monohexyl, monooctyl, and monodecyl phosphates (6.10 mmol) were dissolved into 50 ml of distilled-deionized water free from CO 2 in a sealed polypropylene vessel by stirring for 1 h at room temperature.…”

“…Alkyl phosphates are major organic phosphates in animal organisms, e.g., vesicle membrane, DNA, and ATP, and are sources of hard tissues. Previously, we studied the interactions between CaHap and alkyl phosphate ions (1)(2)(3), between Ca 2+ and alkyl phosphate ions (4), and between Al 3+ and alkyl phosphates ions (5,6). These studies indicated that the calcium alkyl phosphate (CaAP) and aluminum alkyl phosphate (AlAP) are composed of a layered structure alternating bimolecular layer of alkyl phosphates and hydrated calcium or aluminum phosphate phase.…”

Effects of Pore–Pore Correlations on Capillary Condensation in an Ensemble of Slit-like Pores: Application of a Density Functional Theory

“…The second integral in Eq. [3] represents the mean-field approximation for the attractive force contribution. For the Lennard-Jones fluid we apply the following scheme for separation of the potential (17),…”

“…In the case of several natural adsorbents as, for example, molecular sieves, clay minerals, carbosils, or graphitized carbons (3)(4)(5)(6)(7)(8)(9)(10), the walls separating particular pores may be thin enough that they do not screen completely the interaction between particles confined in different pores. In such cases the correlations between molecules adsorbed in neighboring pores may play a non-negligible role, causing the phase behavior of a fluid adsorbed in a set of pores to be different from that evaluated for separated pores.…”