Source of Al ions in secondary brine
Thread Content
This post was last edited by sunjl1981 on 2013-1-6 at 23:56. Recently, the Al ion level has periodically exceeded the acceptable limits during the double-saltwater cycle, but the levels of calcium, magnesium, iron, silicon, and other elements are all within ideal ranges. Have any other colleagues encountered a similar situation? # + + .
I think the problem arose with the primary brine; try reducing the operating time of the Kaier membrane filter. Aluminum ions exist mainly in colloidal form in the raw brine, and they decompose there. At the same time, reduce the amount of alkali added to the primary brine.
I have come across some information indicating that substances such as silica contain large amounts of Al; moreover, some aluminate compounds are stable under alkaline conditions but unstable under acidic conditions, and this might be the reason for it
There is also the aluminum introduced during the treatment of sulfate ions, which is generated during the homemade production of barium chloride.
Personal opinion: AL is mainly introduced by the raw salt; after all, no aluminum elements are added to the saline water, nor are any AL devices used in such cases
It’s baffling why Al was not detected in the first saltwater sample, but suddenly appeared in the second one
Our factory also has an extremely high level of AL ions, around 400 PPb, though it sometimes drops to around 200 PPb – the level is very unstable. AL ions mainly get in from external sources, and we are currently trying to find ways to remove them, but so far with little success
I believe the high AL content in the brine is caused by an excessively high pH level of the brine; such a high pH causes AL ions to exist in the form of aluminate ions, which cannot be removed by the cation exchange resin column
This may be related to your testing method; generally, in ICP detectors, AL can be detected in any form it exists in
The aluminum in the brine can be analyzed again using an ICP instrument. Generally, the aluminum content does not change during the secondary brine treatment process.