Protocols for atomistic modeling of water uptake into zeolite crystals for thermal storage and other applications

Abstract

We report numerical protocols for describing the water uptake process into microporous materials, with special emphasis on zeolite crystals. A better understanding and more predictive tools of the latter process are critical for a number of modern engineering applications ranging from the optimization of loss free and compact thermal storage plants up to more efficient separation processes. Water sorption (and desorption) is indeed the key physical phenomenon to consider when designing several heat storage cycles, whereas water infiltration is to be studied when concerned with sieving through microporous materials for manufacturing selective membranes (e.g. water desalination by reverse osmosis). Despite the two quite different applications above, in this article we make an effort for illustrating a comprehensive numerical framework for predicting the engineering performances of microporous materials, based on detailed atomistic models. Thanks to the nowadays spectacular progresses in synthesizing an ever increasing number of new materials with desired properties such as zeolite with various concentration of hydrophilic defects, we believe that the reported tools can possibly guide engineers in choosing and optimizing innovative materials for (thermal) engineering applications in the near future.

Transport mechanisms of water molecules and ions in sub-nano channels of nanostructured water treatment liquid-crystalline membranes: a molecular dynamics simulation study

“…The structures of the ionic LC compounds that form the sub-nano channels are flexible and are involved in strong electrostatic interactions with water molecules. These features of LC membranes are not seen in hard materials that have been considered for use as water treatment materials, such as zeolite [30][31][32] and CNTs. [13][14][15][16][17][18][19][20] Elucidating how each of these features affects the permeability of water molecules and ions in sub-nano channels will contribute greatly to elucidating the factors that determine the water treatment performance.…”

Thermal transmittance in graphene based networks for polymer matrix composites

“…graphene, graphene nanoribbons carbon nanotubes) have received increasing attention due to their superior properties, for instance high electrical conductivity, shielding ability, transparency, exibility, electromagnetic interference, low thermal expansion, mechanical stiness [7,8], large thermal conductivity [9,10], and selective mass transport [11,12,13]. Instead, the low thermal conductivities of common polymers (≈ 0.2 -0.5 W/mK) have been always a technological limit for industrial applications such as heat exchangers, thermal energy storage systems, electronic systems and machinery [14,15]. Therefore, the introduction of highly conductive llers in thermally insulating polymers is expected to enhance the overall thermal and mechanical properties of the resulting polymer matrix composites by some orders of magnitude [4,16,17].…”

Nonequilibrium molecular dynamics simulations of nanoconfined fluids at solid-liquid interfaces

“…4,5 Molecular modelling of fluid flow in the vicinity of a solid substrate is also of fundamental interest, as it involves a wide spectrum of non-trivial physical phenomena across scales, such as hard-sphere repulsion, slip, viscous forces, and disjoining pressure effects. 3,[6][7][8][9][10][11][12][13] As such it can serve as a paradigm for physical systems exhibiting multiscale dynamics.…”