PDF Publication Title:
Text from PDF Page: 018
Membranes 2021, 11, 575 efficiency was observed for the CMX membrane, as it achieved a higher electric current density at a lower potential difference. This can be attributed to the fact that the CMX membrane has 13–21% less thickness than the CMB membrane (see Table 7), and an elec- trical resistance 22–24% lower (see Table 1). For the application of the membranes in LiOH production, the selected concentra- 18 of 29 tions and flux rates (1.0–1.4 cm/s) were adequate for lithium transport through cationic membranes without reaching the limiting current density. Figure 9. Linear sweep voltammetry in cationic membranes. Figure 9. Linear sweep voltammetry in cationic membranes. 3.3.2. Linear Sweep Voltammetry on Bipolar Membranes under Production Conditions 3.4. Long-Running Production Tests of LiOH by BMED Figure 8 presents current–voltage curves for Fumasep FBM and Neosepta BP mem- Long-running tests of LiOH production were performed using two different bipolar branes at different degrees of LiOH and HCl concentration. The A/V ratio (amperes/voltage) membranes (Neosepta BP and Fumasep FBM) and cation-exchange membranes (CMX has a linear behavior for measured potential range. When comparing the effects of LiOH and CMB) (Table 5). The current densities used were 500 and 1000 A∙m−2. These current and HCl concentration processes, for the same current density, the voltage drop tends to de- densities were chosen according to the LSV results in order to reduce salt leakage through crease when reaching a concentration of 2.5 wt% LiOH and 3.5 wt% HCl. Then, it presents the bipolar membranes (see Figure 7). The initial LiCl feed concentration was between 14 a tendency to increase at higher concentrations (LiOH 5.0 wt% and HCl 7.8 wt%). For both and 34 wt%. Initial LiOH and HCl concentrations equal to 0.5 wt% were used in all tests. types of membrane, the highest A/V value is obtained for 2.5 wt% LiOH and 3.5 wt% HCl The obtained results are summarized in Table 8. concentrations. This means lower apparent electrical resistance of the membranes at such concentrations, which can be attributed to increased electrolytic conductivity in the solution 3.4.1. Product Purity on the membrane surface and osmotic deswelling at higher concentrations (LiOH 5.0 wt% Among the results, Figure 10 shows variation in LiOH and Cl− ion concentrations and HCl 7.8 wt%), leading to an increase in membrane electrical resistance [56]. When over time according to different operating conditions. The presence of chloride as an im- LiOH and HCl concentration increases—up to 5.0 wt% and 7.8 wt%, respectively—A/V purity can be attributed to the leakage of Cl− into the bipolar membrane and undesired ratio decreases and apparent electrical resistance increases, suggesting that there is an transport of this anion across the cation-exchange membrane, due to high LiCl concentra- optimal concentration value close to 2.5 wt% LiOH and 3.5 wt% HC−l, where the membrane tion and its effect on co-ion concentration in the membrane [48]. Cl molar flux into the voltage drop is lower. Regarding the increase in the electrical resis−2tan−1ce of the bipolar LiOH compartment was calculated to be between 0.47 and 1.06 mol∙m ∙h when using a membrane at concentrations of 5.0 wt% LiOH and 7.8 wt% HCl, this− can be attributed to 14wt%LiClconcentration,whereasfora34wt%LiClconcentration,Cl fluxwasbetween concentrated electrolyte that is absorbed by the membrane [57]. At high concentrations, the effect of membrane dehydration has been observed [56,57]; at the same time, membrane conductivity decreases due to absorbed electrolyte by the membrane. At 5.0 wt% HCl and 7.8 wt% LiOH concentrations, the Fumasep FBM membrane exhibits higher apparent electrical resistance than the Neosepta BP membrane. This can be attributed to its higher electrolyte absorption compared to the Neosepta FBM membrane (see Table 6). The latter is associated with a lower electric charge density, which is inversely proportional to water uptake [58]. The dissociation voltage of water in bipolar membranes has been reported to be 0.83 V, but it is usually higher in practical applications [59,60]. In the case of linear sweep voltam- metry in Figure 8, the dissociation voltage measured for the Fumasep FBM and Neosepta BP membranes was 0.76–0.80 V and 0.82–0.84 V, respectively. Low water dissociation volt- ages observed for the Fumasep FBM membrane have also been reported by Xu et al. [61], and can be attributed to an exergonic secondary neutralization reaction between the OH− and H+ ions, which reduces the electrical energy requirement for water electrolysis. OnPDF Image | Bipolar Membrane Electrodialysis for LiOH Production
PDF Search Title:
Bipolar Membrane Electrodialysis for LiOH ProductionOriginal File Name Searched:
membranes-11-00575-v2.pdfDIY PDF Search: Google It | Yahoo | Bing
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)