Brine
Boron removal from MgCl2 and NaCl
brine
Magnesium is the 8th most abundant element and constitutes 2% of the earth's crust. It is present at 0.13% in seawater. Magnesium and its compounds are produced from seawater, well and lake brines and bitterns, as well as from minerals like Magnesite.
High purity magnesium oxide for sintered magnesia refractories is made by pyrohydrolysis of magnesium chloride brine. The presence of boron in the magnesium chloride brine is undesirable because boron embrittles the magnesia ceramics during drying operations. The presence of boron also prevents the coalescence of magnesium metal during electrolysis of fused magnesium chloride salts.
In both cases, boron can be removed from the magnesium chloride brine by using Amberlite™ IRA743 which is a boron-selective resin with N-methyl glucamine functionality. Amberlite™ IRA743 is capable of reducing boron concentrations from around 100 ppm to <10 ppm in 12% MgCl2.
Fig. 1: Boron Removal Process
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Typical Operating conditions*
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Process configuration |
Merry-go-round with 2 or 3 columns |
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Influent Composition |
100 ppm Boron in 12% MgCl2 |
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Flow rate |
16 BV/h |
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Typical operating capacity |
2 g/LR |
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Regenerant mode |
Co-flow |
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Regeneration step |
10% H2SO4 (50 g/LR) |
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Conversion step |
4% NaOH at 4 BV/h for 30-45 min (80-120 g NaOH/LR) |
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Regeneration |
4% NaOH (65 g/LR) or 4 % NH4OH (50 g/LR) |
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Effluent quality |
< 10 ppm B |
* depending on the plant lay out, acceptable leakage levels and influent composition,
these values may change considerably.
Recommended Product
| Very low boron leakage. Excellent operating capacity and low regenerant consumption. High physical and chemical stability. Improved operating capacity. |
For sampling, pricing, availability or more information please contact your Rohm and Haas representative.

