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Membranes 2022, 12, 373 13 of 29 Membranes 2022, 12, x 3.2.2. Membrane Solvent Extraction Owing to the promising performance shown in solvent extraction (see Section 3.1.2 solvent extraction for more details), recent attention has been drawn to the fabrication of membranes which support such extractions. The membranes are used to promote the solvents ability to extract the desire materials, and hence reduce the volume of waste typically produced by solvent extraction alone. Creating a homogeneous interface, these operations use supported liquid membranes (SLMs) which have previously demonstrated high selectivity and low energy utilization [88,89]. SLMs have been the subject of many recent investigations for the separation of metal ions from industrial waste effluents using a variety of extractants. For example, they could act as ion exchange membranes for the lithium ions whilst blocking the organic solvent from passage to an aqueous solution [88]. In a recent study, successful lithium separation via SLMs has been achieved by complexation or binding with specific chemical species. Song et al. studied polyethersulfone (PES) and sulfonated poly-phenyl ether ketone (SPPESK) in the synthesis of hydrophilic nanoporous membranes as a stabilizing barrier for liquid-liquid membrane extraction of lithium ions. In this study, using tributylphosphate (TBP) as the extractant and kerosene as the diluent, lithium extraction and stripping were demonstrated in both single-staged and sandwiched membrane extraction contactor systems [88]. In their following studies, Song et al. further improved the stability of similar membranes, such as poly(ethylene-co-vinyl) (EVAL). The membrane structure provided good chemical resistance with reduced swelling (ethyl section) and created a hydrophilic domain for ion transportation (vinyl alcohol section) [90]. In this case, the lithium diffused from the brine solution towards the membrane interface and crossed over the swollen membrane. Upon arrival at the extraction interface, the lithium bonded with cationic compounds in the extractant fluid to form LiFeCl4 which released the previously attracted Na+ ion. This Na+ ion then passed through the membrane in the reverse mechanism as Li+. This entire process was driven by the concentration gradient in an osmosis mechanism (Figure 11) [90]. Overall, the results gave a linear correlation between the Li feed concentration and the concentration of extraction with the greater EVAL content, suppressing macro voids to provide a more compact structure. This is believed to be due to the unique properties of the materials. ++ ++ Figure 11. Concentration profiles of Li and/or Li complex in the membrane extraction process. Figure 11. Concentration profiles of Li and/or Li complex in the membrane extraction process. “CP”: concentration polarization; “F”: Feed phase; “O”: organic phase; “m”: membrane; “b”: bulk “CP”: concentration polarization; “F”: Feed phase; “O”: organic phase; “m”: membrane; “b”: bulk phase [90]. phase [90]. Although these membranes have been considered as successful applicants for liquid- membrane extractions, SLMs still have some issues with stability, durability and solvent leakage. Conquering these shortcomings requires future research into the fabrication of the organic membranes whilst maintaining hydrophilicity to increase solvent resistance and reduce membrane swelling for reduced fouling [89]. 14 of 29PDF Image | Lithium Harvesting using Membranes
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Product and Development Focus for Infinity Turbine
ORC Waste Heat Turbine and ORC System Build Plans: All turbine plans are $10,000 each. This allows you to build a system and then consider licensing for production after you have completed and tested a unit.Redox Flow Battery Technology: With the advent of the new USA tax credits for producing and selling batteries ($35/kW) we are focussing on a simple flow battery using shipping containers as the modular electrolyte storage units with tax credits up to $140,000 per system. Our main focus is on the salt battery. This battery can be used for both thermal and electrical storage applications. We call it the Cogeneration Battery or Cogen Battery. One project is converting salt (brine) based water conditioners to simultaneously produce power. In addition, there are many opportunities to extract Lithium from brine (salt lakes, groundwater, and producer water).Salt water or brine are huge sources for lithium. Most of the worlds lithium is acquired from a brine source. It's even in seawater in a low concentration. Brine is also a byproduct of huge powerplants, which can now use that as an electrolyte and a huge flow battery (which allows storage at the source).We welcome any business and equipment inquiries, as well as licensing our turbines for manufacturing.CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)