Advanced Characterization in Clean Water Technologies

Abstract

Desalination technologies, which remove solutes from water, are essential to the purification of water for agricultural and industrial purposes and for potable use. While a variety of desalination technologies exist, their performance and durability need improvements to meet future clean water demands. This challenge is particularly complex as a variety of feed water sources exists, which contain various amounts of salt, dissolved organic matter, suspended particulates, and other contaminants. Hence, predictive knowledge of the underlying physics and chemistry at the atomic and molecular scale is crucial for designing improved desalination materials and processes. In this Perspective, we outline how advanced characterization techniques, including X-ray, neutron, electron-based, and positron-based methods can be advantageously applied to water desalination technologies to provide detailed molecular insight, especially when combined with computational modeling. We summarize some of the scientific challenges in two prominent desalination techniques, membrane reverse osmosis and capacitive deionization, and lay out some specific approaches toward solving these challenges. With these developments, we anticipate that the use of advanced characterization can help advance the field of water desalination in much the same way that these have aided progress in energy storage and conversion science over the last decades.

Diffusioosmosis-driven dispersion of colloids: a Taylor dispersion analysis with experimental validation

“…2014; Bone et al. 2020; Gupta et al. 2020 a , c ; Henrique, Zuk & Gupta 2022) it is common to observe ion concentration gradients inside charged pores, where one can expect colloidal transport and dispersion to be important.…”

“…To enable widespread use of diffusiophoresis in lab-on-a-chip applications such as energy storage and desalination devices (Bone, Steinrück & Toney 2020; Gupta et al. 2020 a ; Gupta, Zuk & Stone 2020 c ), particle separation (Lee et al.…”

Designing Solute-Tailored Selectivity in Membranes: Perspectives for Water Reuse and Resource Recovery

“…Simulations provide an efficient route to design novel materials maximizing selectivity, as demonstrated by efforts coupling high-throughput computation paired with optimization techniques for inverse materials design, such as those that control water behavior . Combining insights from simulation with transport measurements and advanced characterization techniques (e.g., synchrotron spectroscopy) will enable a deep understanding of these novel materials. − …”

Ion Correlations and Their Impact on Transport in Polymer-Based Electrolytes

“…Polymer-based electrolytes play a crucial role in a wide range of systems, including energy storage devices, − membrane-based separation technology, − and biological processes and applications. − These materials include solid polymer electrolytes, which consist of salts dissolved in a high molecular weight polymer host, as well as polyionic systems, where one of the ions is incorporated into a polymer chain. The latter, typically called single-ion conductors, may be dry or include additional solvent to form either a gel or a fully dissolved polyelectrolyte solution. , For the specific case of energy storage applications such as batteries, the adoption of polymer-based electrolytes is largely limited by the transport properties of these systems. , Poor transport can result in additional overpotentials and detrimental concentration gradients that can limit the efficiency and rate capability of the device. , …”