Registration Dossier

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

The information on the physical and chemical properties were from experimental results with test sample provided by Lead Registrant, or either cited from peer-reviewed database or handbooks, or publications. These studies followed standard guidelines for methodology and so the data is considered reliable and suitable for use. Expert judgement-based waiving are applied for the endpoints on which tests are not necessary.

The reference substance Aluminium chlorohydrate (dialuminium chloride pentahydroxide) is a dense, crystalline powder at ambient temperature, with negligible volatility anticipated. In water, it is very soluble, without surface-active properties, and complex pH-dependent speciation.

It is not classified for physical hazards, based on CLP criteria, but solutions may be corrosive to metals.

Additional information

Summary of relevant physico-chemical properties:




Solid (white crystalline powder)

Melting Point / Boiling Point

primary decomposition corresponding to crystal water loss from ca 75°C;

no mp/bp up to 400°C

Relative density

1.95 (true density)



Vapour pressure

Not required (mp>300°C), expected << 0.01 Pa.

Partition coefficient

Not required (inorganic)

Water solubility

Aluminium chlorohydrate is considered as a very soluble salt (>> 100 g/L), however aluminium speciation rapidly leads to salting out to various degrees which are water quality-, and especially highly pH-dependent. Solubility of monomeric Al can descend as low as 12 µg Al/L.

Surface tension

75.3 mN/m at 1 g/L


Flash Point not required (solid, inorganic)

No propagation of combustion, not a flammable solid.

Not self-heating.

Not pyrophoric.

No release of flammable gas anticipated if contact with water (based on experience).

Explosive properties

No potential (based on chemical structure).

Oxidising properties

No potential (based on chemical structure).

Stability in organic solvents

Not required (inorganic)

Dissociation constant

Not required (forms various hydroxides and polymeric species, depending on pH).

Self-reactive properties

No potential (based on chemical structure).

Organic peroxide

Not a peroxide (inorganic).

Metal corrosivity

100% mass loss on aluminium with 2 days (from analogue).

Numerical values above are given for a typical grade containing 24.7%w/w Al.

As an UVCB, it should be noted that the above parameters may show some variations.