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Aluminium tris(dihydrogen phosphate) (CAS 13530-50-2) is an inorganic substance and does not undergo biological degradation. The substance is mainly removed from water through chemical precipitation and abiotic processes. Aluminium tris(dihydrogen phosphate) dissociates to dihydrogen phosphate and aluminium ions in aqueous and biological system. The ions are present in the most stable oxidation states (as Al+3 and P+5) in all environmental compartments. The ions do not undergo oxidation-reduction transformation under normal environmental conditions.

As elements aluminium and phosphorus are persistent in environment. Aluminium can participate in hydrolysis reactions, thereby forming a number of monomeric and polymeric Al-hydroxyl species and this process is highly dependent upon pH values. At the neutral pH in the range of 5 and 8 aluminium forms mainly insoluble aluminium hydroxides that precipitate out of solution. The dihydrogen, hydrogen phosphate and orthophosphate anions maintain dissociation equilibrium in the aquatic environment and act as a buffer over a pH range of 6 – 8. Phosphate ions can be removed from the water column through incorporated into either biological solids (e.g. microorganisms) or chemical precipitates. Orthophosphate is available for biological metabolism without further breakdown. Besides chemical precipitation phosphate can also be biologically removed from waste water. Microorganisms to take up phosphate into their cells either via aerobic or anaerobic pathways: The phosphate is subsequently removed from the STP process as a result of sludge wasting.