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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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: 939-582-4 | CAS number: 1471315-26-0
Dissociation constant
Administrative data
Link to relevant study record(s)
Description of key information
Not applicable for Fatty acids, C16-18 (even numbered), aluminum salts
Palmitic acid (57-10-3): pKa = 4.75 (est.)
Stearic acid (57-11-4): pKa = 4.75 (est.)
Behaviour of aluminium in water is very complex. Aluminium speciation depends strongly on pH:
pH < 5.7: Al3+ and [Al(OH)2]+
pH 5.7 to 6.7: [Al(OH)]2+, [Al(OH)2]+ and Al(OH)3
pH > 6.7: [Al(OH)4]-, polymerization
Key value for chemical safety assessment
Additional information
The test is scientifically not possible to perform: Fatty acids, C16-18 (even numbered), aluminum salts is not soluble in water. Furthermore for complex mixtures (UVCB) with ionisable components the assessment of pKa is clearly complicated.
pKa values of the two main fatty acid components from literature are given instead.
The behaviour and dissociation of aluminum is common knowledge, as described in the assessment report for the three aluminum salts (chloride, nitrate and sulphate) under the Canadian Environmental Protection Act: At low pH values, dissolved aluminum is present mainly in the aquo form (Al3+). Hydrolysis occurs as pH rises, resulting in a series of less soluble hydroxide complexes (e.g. Al(OH)2+, Al(OH)2+). Aluminum solubility is at a minimum near pH 6.5 at 20 °C (Al(OH)3) and then increases as the anion, Al(OH)4-, begins to form at higher pH.
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.
