| There are two major ways of producing magnesium [1]: 1) Electrolytic production from anhydrous magnesium chloride, similar to the electrolytic production of aluminum. 2) The Pidgeon process, which currently dominates Chinese (and world) magnesium production. It distills magnesium vapor under vacuum from a heated mixture of ferrosilicon and magnesium-calcium oxide (calcined dolomite). The Pidgeon process has a high global warming potential because of the coal used to produce the ferrosilicon input and to heat the retorts. The electrolytic process has a lower global warming potential, especially if using low-carbon electricity, but historically sulfur hexafluoride has been used as a protective cover gas for the metal during electrolytic production. This gas has a staggering global warming potential 23,900 times that of CO2 [2] so incidental leakage of even small quantities can have a high climate impact. The "without mining" part is not novel. Dow Chemical produced electrolytic magnesium from seawater without mining at Freeport, Texas from 1941-1998, until lower cost foreign magnesium made it uneconomical: https://www.chemicalonline.com/doc/dow-to-exit-magnesium-bus... Reading the company's rather sparse public info, it looks like this is a revival of the same basic kind of process as Dow used. But since it's focused on certifying a low GWP for its magnesium, the company will not use sulfur hexafluoride. ("We’re piloting a new generation of electrolytic production technology that is inherently carbon neutral, removing the need for coal and carbon-intense reagents like FeSi and SF6.") They don't say it directly but they also must be using clean electricity for the electrolysis, otherwise the metal would still be fairly CO2-intensive. Unfortunately, the latest news item from their news page is about a threat to their business: "State of Utah denies US Magnesium’s request to extend canals into the Great Salt Lake threatening shutdown of the only American magnesium producer" https://sltrib.pressreader.com/article/6830844853434424 [1] https://ro.uow.edu.au/cgi/viewcontent.cgi?article=2295&conte... [2] https://en.wikipedia.org/wiki/Sulfur_hexafluoride#Greenhouse... |