Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 237-415-3 | CAS number: 13776-88-0
Adsorption / desorption
Administrative data
Link to relevant study record(s)
Description of key information
Key value for chemical safety assessment
Additional information
Aluminium metaphosphate (CAS 13776-88-0) is an inorganic phosphate compound. The substance can be transformed by hydrolysis forming aluminium species and soluble orthophosphate (PO43-) in sewerage systems, sewage treatment plants and in the environment. The mobility of aluminium species is very complex and difficult to predict in areas affected by a number of geochemical factors which can affect the formation of speciation of aluminium and adsorption and desorption of aluminium on suspended particles. The relative mobility of aluminium species, depend upon on many factors, especially pH, alkalinity, temperature, dissolved organic carbon, dissolved inorganic carbon and anion concentration. At low pH (less than 5.5), aluminium is present is the predominant as Al3+ species, which is highly mobile. As pH increases above 5.5, aluminium-hydroxide complexes and organically complexed aluminium formed either by hydrolysis and combined with organic matters. Above pH 7, anionic aluminium hydroxide predominates. Kaplan (2005) published several Kd values based on measured Al concentration in groundwater and sediment and suggested Al Kd values for soil, grout, gravel, clay to be 3700 mL/g and 5000 mL/g for concrete, respectively. Furthermore, aluminium species play itself also an important role in the adsorption of other trace metal or anions in soils and sediments. Furthermore, colloidal aluminium species play also an important role in the adsorption of other trace metals and anions in soils and sediments.
Phosphorus retention in soils is influenced by the form of P released. Triphosphate is a condensed phosphorus species with three phosphate units. Busman studied the adsorption of polyphosphate by soils and clay minerals and indicated that affinity of polyphosphate increased with increasing length of phosphate units, and adsorption of triphosphate was more strongly adsorbed than orthophosphate, whereas mobility and solubility of triphosphate increased by hydrolysis in soils to orthophosphate (Busman 1984).
Reference
Busman, Lowell Marion, "Behavior of polyphosphates in soils " (1984). Retrospective Theses and Dissertations. Paper 8979.
Kaplan D.I. (2005) Recommended Distribution Coefficients, Kd Values, for Special Analysis Risk Calculations Related to Waste Disposal and Tank Closure on the Savannah River Site (U), Westinghouse Savannah River Company Savannah River Site,
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
