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Title: Macroscopic Modeling and Phase Field Modeling of Solar Grade Silicon by Molten Salt Electrolysis
DOI: 10.1007/978-3-030-92559-8_5 The sixth Intergovernmental Panel on Climate Change report (IPCC) recently released predicts a deep reduction in emissions to meet global goals of 1.5 °C reduction in temperature. It states that concentrations of CO₂ have continuously increased in the atmosphere reaching averages of 410 ppm in 2019. Therefore, it becomes imperative to reduce CO₂ in any way possible. Silicon, which is an important material for renewable energy, electronics, and metallurgy, is primarily produced by the carbothermic reduction of quartz. This metallurgical grade silicon is then refined by the Siemens Process to solar grade silicon using hydrogen chloride. The by-product of trichlorosilane from this process is highly volatile and unstable. This work aims to achieve the above process of reduction in a single step using electrochemistry. This would eliminate multiple steps and save energy and cost and reduce emissions if a suitable inert anode is used in production. Understanding electrochemical cell characteristics therefore is needed to prove and scale this technology. Macroscopic models help engineers to design, develop, and improve the efficiency of electrochemical cells. They solve conservation equations of mass, momentum, and energy and help determine electrode current distribution, fluid flow, heat distribution, and stability of the cell. They also help in correlating experimental work and understanding measurements in cells from a lab scale to a plant scale. However, they do not predict the microstructure and plating of material on the cathode. This can be calculated using phase field models. These phase field models predict interface stability and deposition morphology in the cell. In this work, we present these models in addition to proof-of-concept experiments.  more » « less
Award ID(s):
1937818
PAR ID:
10389320
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Editor(s):
Tesfaye, Fiseha; Zhang, Lei; Guillen, Donna Post; Sun, Ziqi; Baba, Alafara Abdullahi; Neelameggham, Neale R.; Zhang, Mingming; Verhulst, Dirk E.; Alam, Shafiq
Date Published:
Journal Name:
REWAS 2022: Energy Technologies and CO2 Management (Volume II)
Page Range / eLocation ID:
41-45
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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