{"id":25685,"date":"2022-09-26T13:07:03","date_gmt":"2022-09-26T12:07:03","guid":{"rendered":"https:\/\/www.innovationnewsnetwork.com\/?p=25685"},"modified":"2022-09-26T13:07:03","modified_gmt":"2022-09-26T12:07:03","slug":"new-method-extract-magnesium-from-seawater","status":"publish","type":"post","link":"https:\/\/www.innovationnewsnetwork.com\/new-method-extract-magnesium-from-seawater\/25685\/","title":{"rendered":"New method to extract magnesium from seawater"},"content":{"rendered":"
For thousands of years, the ocean has acted as a source of minerals and salts for humans. It is widely known that sodium chloride, table salt, has been extracted from seawater for a long period of time. Today, researchers are analysing which minerals can be removed from the sea as extracting minerals from seawater is not an energy-intensive process. Especially as the world transitions to clean energy, it is essential to reduce the environmental hazards that typically arise from mining critical minerals on the land. Researchers are therefore looking into extracting critical and strategic materials from seawater, specifically magnesium.\u00a0<\/span>\u00a0<\/span><\/p>\n Magnesium has a variety of potential uses in clean energy technologies, including in carbon capture, low-carbon cement, and <\/span>next-generation batteries<\/span><\/a>. The U.S. Department of Energy has recently included magnesium on its <\/span>list of critical materials<\/span><\/a> for domestic production. Despite the metal\u2019s use in these important technologies, the US\u2019 method for obtaining the material is currently at risk. The existing process for magnesium extraction in the US is through an energy-intensive process from salt lake brines, some of which are in danger due to increasing droughts. Extracting magnesium from seawater will help secure domestic production of the material whilst reducing the environmental impact compared to the current extraction process.\u00a0<\/span>\u00a0<\/span><\/p>\n Researchers at <\/span>Pacific Northwest National Laboratory (PNNL)<\/span><\/a> and the <\/span>University of Washington (UW)<\/span><\/a> have discovered a way to isolate a pure magnesium salt, a feedstock for magnesium metal, from seawater. Their new method, named the laminar coflow method, flows two solutions side-by-side in a long stream. The process takes advantage of the fact that the flowing solutions create a constantly reacting boundary, as fresh solutions flow by and never allow the system to reach a balance.<\/span>\u00a0<\/span><\/p>\n The study was published in <\/span>Environmental Science & Technology Letters<\/span><\/i>.<\/span>\u00a0<\/span><\/p>\n In the mid-20th century, magnesium feedstock was created by chemical companies by mixing seawater with sodium hydroxide, known as lye. The resulting magnesium hydroxide salt was then processed to make magnesium metal. However, this process resulted in a complex mixture of magnesium and calcium salts, which are costly to separate.<\/span>\u00a0<\/span><\/p>\n The laminar coflow method involves flowing seawater alongside a solution with hydroxide. The magnesium-containing seawater quickly reacts to form a layer of solid magnesium hydroxide. This thin layer acts as a barrier to solution mixing.<\/span>\u00a0<\/span><\/p>\n \u201cThe flow process produces dramatically different results than simple solution mixing,\u201d said PNNL postdoctoral researcher Qingpu Wang. \u201cThe initial solid magnesium hydroxide barrier prevents calcium from interacting with the hydroxide. We can selectively produce pure solid magnesium hydroxide without needing additional purification steps.\u201d<\/span>\u00a0<\/span><\/p>\n This new process produces pure magnesium hydroxide, allowing researchers to skip energy-intensive and expensive purification steps.<\/span>\u00a0<\/span><\/p>\n PNNL chemist and UW Affiliate Professor of Materials Science and Engineering Chinmayee Subban said: \u201cNormally, people move separations research forward by developing more complicated materials.<\/span>\u00a0<\/span><\/p>\n \u201cThis work is so exciting because we\u2019re taking a completely different approach. We found a simple process that works. When scaled, this process could help drive the renaissance of US magnesium production by generating primary feedstock. We’re surrounded by a huge, blue, untapped resource.\u201d<\/span>\u00a0<\/span><\/p>\nExtracting magnesium salt from seawater<\/h3>\n