Evaluation of various water models for simulation of adsorption in hydrophobic zeolites

Castillo, J.; Dubbeldam, David; Vlugt, Thijs J. H.; Smit, Berend; Calero, Sofı́a

doi:10.1080/08927020902865923

Cited by 68 publications

(89 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In a previous work 11 , we justified the use of this water model for studying the adsorption of water in zeolites. The water-zeolite and water-cation interactions were fitted to the experimental data obtained in this work.…”

Section: Methodsmentioning

confidence: 97%

“…Molecular simulation studies also reveal large differences in adsorption depending on the simulation parameters and the models employed. In a previous work 11 , we studied water adsorption in hydrophobic zeolites by molecular simulation. We showed that water adsorption was extremely sensitive to small changes in the force field parameters, the selection of water model, the position of the framework atoms, and the partial charges of the zeolite atoms.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Water adsorption in hydrophilic zeolites: experiment and simulation

Castillo

Silvestre-Albero

Rodriguez-Reinoso

et al. 2013

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

We have measured experimental adsorption isotherms of water in zeolite LTA4A, and studied the regeneration process by performing subsequent adsorption cycles after degassing at different temperatures. We observed incomplete desorption at low temperatures, and cation rearrangement at successive adsorption cycles. We also developed a new molecular simulation force field able to reproduce experimental adsorption isotherms in the range of temperatures between 273 K and 374 K. Small deviations observed at high pressures are attributed to the change of the water dipole moment at high loadings. The force field correctly describes the preferential adsorption siting of water at different pressures. We tested the influence of the zeolite structure, framework flexibility, and cation mobility when considering adsorption and diffusion of water. Finally, we performed checks on force field transferability between different hydrophilic zeolite types, concluding that classical, non-polarizable water force fields are not transferable. 2

show abstract

Section: Methodsmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

Water adsorption in hydrophilic zeolites: experiment and simulation

Castillo

Silvestre-Albero

Rodriguez-Reinoso

et al. 2013

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…It is for this reason that new force fields have been optimized for pure silica zeolites [51][52][53] and also for those with nonframework sodium, calcium, and protons [16,[54][55][56]. The new force field parameters provide quantitative good predictions for adsorption and molecular transport in these systems [16,[51][52][53][54][55][56][57][58]. Most molecular simulation studies in zeolites are performed using the Kiselev-type potentials, where the zeolite atoms are held rigid at the crystallographic positions [59].…”

Section: Modeling Zeolites and Nonframework Cationsmentioning

confidence: 99%

“…For simple molecules such as carbon dioxide, nitrogen, hydrogen, oxygen, or even water, rigid models with multipoles or polarization seem a good representation [30,56,57,[69][70][71][72][73][74][75][76][77][78]. Complex molecules such as hydrocarbons normally require flexible models.…”

Section: Modeling Guest Moleculesmentioning

confidence: 99%

Modeling of Transport and Accessibility in Zeolites

Calero¹

2010

Zeolites and Catalysis

View full text Add to dashboard Cite

IntroductionModeling plays an important role in the field of zeolites and related porous materials. The use of molecular simulations allows the prediction of adsorption and diffusion coefficients in these materials and also provides important information about the processes taking place inside the porous structures at the molecular level [1-10]. Hence, molecular modeling is a very good complement to experimental work in the understanding of the molecular behavior inside the pores.Despite the great interest and the applicability of zeolites, there are still many facets of the molecular mechanisms for a given reaction inside their pores that are poorly understood. These mechanisms are important for (i) the way the zeolite adsorbs, diffuses, and concentrates the adsorbates near the specific active sites; (ii) the interactions between the zeolite and the adsorbates and the effect on the electronic properties of the system; (iii) the chemical conversion at the active site; and (iv) the way the zeolite disperses the final product. Detailed knowledge on the molecular mechanisms involved will eventually lead to an increase in the reaction efficiency.This chapter focuses on molecular modeling of transport and accessibility in zeolites. It describes how simulations have contributed to a better understanding of these materials and provides a summary of the state of the art as well as of current challenges. The chapter is organized as follows. First, common models and potentials are briefly described. This is followed by a general overview on current simulation methods to compute adsorption, diffusion, free energies, surface areas, and pore volumes. The chapter continues with some examples on applications of molecular modeling to processes of interest from the industrial and environmental point of view. Finally, the chapter closes with a summary and some remarks on future challenges.

show abstract

“…[33][34][35] We will not review this large literature here as this was done before. [36][37][38][39][40] On the other hand, despite this remarkable and extensive body of work, water is not yet fully understood. Integral equations and other methods of liquid state theory led to a fairly detailed understanding of Lennard-Jones ͑LJ͒ liquids, such as argon, which are governed by spherically symmetric potentials, and of dipolar liquids, such as acetonitrile or nitroethane, which are governed by dipolar or Stockmayer potentials.…”

Section: Introductionmentioning

confidence: 99%

A statistical mechanical theory for a two-dimensional model of water

Urbič

Dill²

2010

The Journal of Chemical Physics

View full text Add to dashboard Cite

We develop a statistical mechanical model for the thermal and volumetric properties of waterlike fluids. Each water molecule is a two-dimensional disk with three hydrogen-bonding arms. Each water interacts with neighboring waters through a van der Waals interaction and an orientation-dependent hydrogen-bonding interaction. This model, which is largely analytical, is a variant of the Truskett and Dill ͑TD͒ treatment of the "Mercedes-Benz" ͑MB͒ model. The present model gives better predictions than TD for hydrogen-bond populations in liquid water by distinguishing strong cooperative hydrogen bonds from weaker ones. We explore properties versus temperature T and pressure p. We find that the volumetric and thermal properties follow the same trends with T as real water and are in good general agreement with Monte Carlo simulations of MB water, including the density anomaly, the minimum in the isothermal compressibility, and the decreased number of hydrogen bonds for increasing temperature. The model reproduces that pressure squeezes out water's heat capacity and leads to a negative thermal expansion coefficient at low temperatures. In terms of water structuring, the variance in hydrogen-bonding angles increases with both T and p, while the variance in water density increases with T but decreases with p. Hydrogen bonding is an energy storage mechanism that leads to water's large heat capacity ͑for its size͒ and to the fragility in its cagelike structures, which are easily melted by temperature and pressure to a more van der Waals-like liquid state.

show abstract

Evaluation of various water models for simulation of adsorption in hydrophobic zeolites

Cited by 68 publications

References 64 publications

Water adsorption in hydrophilic zeolites: experiment and simulation

Water adsorption in hydrophilic zeolites: experiment and simulation

Modeling of Transport and Accessibility in Zeolites

A statistical mechanical theory for a two-dimensional model of water

Contact Info

Product

Resources

About