Pacific Northwest National Laboratory (PNNL)

Pacific Northwest National Laboratory (PNNL) is developing a radically new process to produce magnesium from seawater. Today’s methods are energy intensive and expensive because the magnesium concentration in seawater is so low that significant energy is needed to evaporate off water and precipitate magnesium chloride salt. Further, conventional technologies involve heating the salt to 900°C and then using electric current to break the chemical bond between magnesium and chlorine to produce the metal. PNNL’s new process replaces brine spray drying with a low-temperature, low-energy dehydration process. That step is combined with a new catalyst-assisted process to generate an organometallic reactant directly from magnesium chloride. The organometallic is decomposed to magnesium metal via a proprietary process at temperatures less than 300°C, thus eliminating electrolysis of magnesium chloride salt. The overall process could be significantly less expensive and more efficient than any conventional magnesium extraction method available today and uses seawater as an abundant, free resource.

If successful, PNNL would enable a low-cost, low-energy metal-organic process for producing magnesium from seawater without the energy intensive steps associated with conventional processes.