pyEQL: A Python interface for water chemistry

Abstract

The properties and behavior of aqueous solutions -that is, water containing dissolved minerals and other solutes -are vital to understanding natural systems and to developing new technologies for water purification, wastewater treatment, and sustainable industrial processes (Stumm & Morgan, 1999). pyEQL provides object representations for aqueous solutions, creating a stable, intuitive, and easy to learn interface for calculating properties of solutions and dissolved solutes. Its purpose is to save researchers time by making a variety of different models accessible through a single interface and by aggregating hundreds of properties and model parameters into a built-in database. Statement of needAccurately predicting the thermodynamic and transport properties of complex electrolyte solutions containing many solutes, especially at moderate to high salt concentrations commonly encountered in water desalination and resource recovery applications, remains a major scientific challenge (Rowland & May, 2019). This challenge is compounded by the fact that the best available models, such as the Pitzer model (May et al., 2011), are difficult to implement on an as-needed basis and require looking up many parameters. Researchers and practitioners in fields such as water treatment and desalination, electrochemistry, or environmental engineering need accurate information about electrolyte solutions to perform their work, but are typically not specialists in solution chemistry or electrolyte thermodynamics.