No abstract

No abstract

Novel electrolysis processes remain strong technological contenders for advances in sustainable materials processing, in particular metals, yet will need to compete economically with currently-deployed production facilities. To evaluate the technoeconomic efficacy of new electrolytic metal extraction processes, an understanding of the capital and operating costs of electrowinning is necessary. Estimation of electrochemical operating costs has been afforded due attention, yet capital cost (CAPEX) trends are far less understood. Herein, we attempt to show that estimating the capital costs of electrowinning processes via conventional chemical engineering scaling laws is not possible. Instead, we propose a capital cost model for electrochemical processes based on relevant operating parameters such as current density, temperature, and voltage. The new model for capital cost describes within ±30 to 100% the capex for existing electrochemical processes, sufficient for order of magnitude and preliminary design capital cost estimation.

The liquid phase thermodynamic of mixing of the copper-aluminium binary system is investigated as a function of temperature and composition using the electrochemical potential difference method. A copper-selective beta" alumina (Cuβ"Al 2 O 3 ) is used as a solid electrolyte, synthesized through ion exchange, sintering from base oxide powders, and the floating zone method of crystal growth. Measured thermodynamic of mixing data were used to inform short range ordering in copper-aluminium melts through Darken's factor for excess stability and Bhatia-Thornton structure factors, revealing a strong departure from ideality and pronounced ordering. Mixing properties were used to predict viscosity and self-diffusion coefficients. Features observed in calculated electronic entropy of mixing for copper-aluminium were compared to trends in viscosity, demonstrating the utility of electronic property of mixing in the description of structure-properties in this liquid binary system.

No abstract

No abstract

No abstract

Processes for recycling lithium ion batteries (LIB), in particular complex chemistries such as those containing nickel-manganese-cobalt oxide (NMC) cathodes, are hindered by tradeoffs between capital cost, process sustainability, and materials recovery. Most metal separations in primary and secondary production of critical elements rely on anion exchange chemistries. Herein, we explore the application of a novel oxide-sulfide anion exchange methodology to facilitate LIB recycling. Beginning with selective sulfidation of NMC cathode oxides, we demonstrate that lithium may be stabilized as a sulfate, manganese as an oxysulfide, and nickel and cobalt as sulfides from the mixed metal feed, potentially facilitating isolation of lithium via leaching and nickel-cobalt via flotation. Following, we explore molten sulfide electrolysis as a method of process intensification, combining separation and reduction into a single unit operation for difficult to separate metals such as cobalt and nickel. We demonstrate selective reduction of cobalt from mixed nickel-cobalt sulfide, as produced in selective sulfidation of waste NMC cathodes, using a barium-lanthanum sulfide supporting electrolyte. Our preliminary results suggest that selective sulfidation as a pretreatment for selective molten sulfide electrolysis is a promising avenue for separation of critical elements from complicated materials feeds, such as those found in lithium ion battery recycling streams.