Theoretical Study of the Adsorption of the Butanol Isomers in H-ZSM-5

Reaction path analysis for 1-butanol dehydration in H-ZSM-5 zeolite: Ab initio and microkinetic modeling

“…On the other hand, a relatively weaker interaction of the alcohol with the zeolite Brønsted acid site leads to a lower partial charge on butanol in the P1 monomer. These results for physisorption are also in line with the previous studies by Nguyen et al [45,46].…”

“…The butanol molecule can be adsorbed either in the straight or in the sinusoidal channel of the H-ZSM-5 framework. Previous theoretical studies on physisorption and protonation of alcohols in H-ZSM-5 have shown that there is no energetic preference for adsorption of 1-butanol in the straight or sinusoidal channel of the zeolite [45,46]. Herein, for the adsorption of a single molecule of 1-butanol, the molecule is considered to be situated in the straight channel, while the second molecule is adsorbed in the sinusoidal channel.…”

“…Dispersive corrections for the van der Waals interactions were included by adding a pairwise interaction term to the Kohn-Sham energy using the DFT-D2 approach proposed by Grimme [38] and extended by Kerber et al [39] for periodic PBE calculations. Although systematic deviations may be observed due to the overestimation of the dispersion interaction [40][41][42][43], DFT-D2 has been widely applied for the theoretical investigation of adsorption [44][45][46][47] and reaction in zeolites [47,48] and is known to provide reasonably accurate results [41,49]. The electronic charge on atoms and fragments was calculated using Bader analysis [50] as implemented by Henkelman et al [51] Transition state search was performed using Nudged Elastic Band (NEB) [52] and dimer [53,54] calculations.…”

First-principles kinetic modeling in heterogeneous catalysis: an industrial perspective on best-practice, gaps and needs

“…77 For alkane, alkene and alcohol adsorption in zeolites these same functionals typically yield as low adsorption strengths as 0.1-0.2 eV per carbon atom, highlighting that it is in fact vdW interactions that are the dominant factor counteracting destabilization by steric constraints. [78][79][80] Ironically, the large self-interaction error of the LDA functional sometimes mimics an artificial contribution of roughly the same size as the missing vdW component. Aware or unaware that this yields ''the right answers for the wrong reason'' this has led some applied works to resort to the doubtful approach of using LDA data as a pragmatic solution to the vdW problem.…”

Adsorption, reduction and storage of hydrogen within ZSM-5 zeolite exchanged with various ions: A comparative theoretical study

“…Density functional theory (DFT) methods are known to be deficient to describe long-range dispersion interactions [51][52][53][54][55]. The hybrid MP2:DFT scheme was proposed to account for the dispersion energies reproducing the reaction barriers with near chemical accuracy [51,52].…”