Development of Novel Ligands used in Ion Flotation for Produced Water Value Extraction

Naturally occurring radionuclides (uranium or thorium), metals of environmental concern (arsenic or lead), and critical metals (rare earth elements) are widely distributed in the earth’s crust. So, it’s no surprise that hydrocarbon extraction processes in the US often produce some waste materials that contain some level of these metals of interest. Both the rapidity and the extent of the U.S. natural gas drilling boom have brought heightened scrutiny to the issues of produced waters containing radioactive materials and/or metals of strategic importance, and there are particular concerns regarding their waste management. For example, produced waters (PW) from the Marcellus Shale hydraulic fracturing operations have shown high uranium content. Fortunately, the risk of this contamination posed to employees or the general public from the NORM is widely held to be minimal. Uranium is considered a “critical mineral” by the US DOE and is an active area of research in the Critical Minerals Sustainability (CMS) program. As are the 17 REEs (La through Lu plus Y and Sc) due to their importance in military, high-tech, and green-tech applications. Recent volatility in global trade has renewed efforts to challenge China’s dominance for both uranium and REEs by establishing a domestic supply and the associated processing facilities.GlycoSurf proposes to focus on the recovery of both uranium and REEs from PWs generated from fracking operations and is collaborating with Pilot Chemical to extract value from PW. GlycoSurf has identified a class of glycolipid molecules, known as rhamnolipids, which exhibit high capture efficiency and selectivity for both uranium and REE, even in the presence of competing ions that are orders of magnitude more concentrated. In Phase I, GlycoSurf intends to combine its proprietary process for the synthetic production of rhamnolipids with ion flotation methods that are well known. In fact, flotation processes are commonly used to treat produced water using conventional treatment trains, but their primary purpose is for removing small size droplets of oil contained within the PW. The potential to combine our unique surfactants with microbubble-enhanced ion flotation for the economic extraction of valuable minerals from PW wastes, represents a new paradigm shift in the development of a low-cost, efficient extraction technology to recover metals from these non-traditional sources. However, there are challenges posed by the chemistry of PW for the extraction and recovery of these elements. The complex composition of PW is highly variable by region; however, GlycoSurf is working with a Marcellus field fracking operation (through Pilot Chemical) to evaluate its specific chemistry. If successful, GlycoSurf in Phase II and beyond, will work with our project partners to implement a new treatment process that will result in an environmentally friendly process having lower costs than are current U and REE separations. Our commercialization strategy will enable this team to work with its industry partners to demonstrate the large-scale deployment of this technology, which will ensure a domestic supply of uranium and critical REEs for industrial.