Experimental and DFT study on titanium-based half-sandwich metallocene catalysts and their application for production of 1-hexene from ethylene

Gharajedaghi, Sajjad; Mohamadnia, Zahra; Ahmadi, Ebrahim; Marefat, Mohamadreza; Pareras, Gerard; Simon, Sı́lvia; Poater, Albert; Bahri‐Laleh, Naeimeh

doi:10.1016/j.mcat.2021.111636

Cited by 12 publications

(21 citation statements)

References 62 publications

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“…Indeed, after the catalyst, the selection of the appropriate cocatalyst is the most important and effective parameter in olefin polymerization processes [10]. The type of cocatalyst not only affects catalyst productivity but also alters the microstructure and arrangement of monomers in polymer chains during the polymerization reaction [11,12]. It is well-known that, in a polymerization process, the cocatalyst i) activates pre-catalyst particles, ii) participates in chain transfer reactions, iii) changes the isotacticity and molecular weight of the polymer [13], and iv) alters the kinetic stability and resistance to the decomposition of catalyst.…”

Section: Introductionmentioning

confidence: 99%

Exploring cocatalyst type effect on the Ziegler–Natta catalyzed ethylene polymerizations: experimental and DFT studies

et al. 2022

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Due to the important role of cocatalyst in the polymerization process employing industrially favored Ziegler–Natta catalysts, its effect on kinetic behavior, catalyst activity, and polymer properties is discussed. In this paper, triethyl aluminum (TEA) and triisobutyl aluminum (TIBA) have been used as the main cocatalyst ingredient with 10–20 mol percent of diethyl aluminum chloride (DEAC) and ethyl aluminum dichloride (EADC) cocatalysts, being neat TEA the cocatalysts with the highest activity. Moreover, TEA-DEAC and TEA-EADC cocatalysts revealed a built-up kinetic profile, while TIBA-DEAC and TIBA-EADC show a decay-type kinetic curve. According to melt flow index results, no considerable change in flowability was detected in the synthesized polyethylenes (PE). On the other hand, the ethylene insertion and chain termination mechanisms were investigated by means of density functional calculations using Ti active center located in (110) and (104) facets of the MgCl2 surface. To shed light on the bulkiness level of employed cocatalysts, buried volume (VBur) together with the two-dimensional map of cocatalyst systems were considered. Higher VBur of TIBA complex can explain its lower activity and decay type kinetic profile obtained by experimental studies.

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Section: Introductionmentioning

confidence: 99%

Exploring cocatalyst type effect on the Ziegler–Natta catalyzed ethylene polymerizations: experimental and DFT studies

et al. 2022

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“…The B3LYP-D3-SMD(THF)/Def2TZVP//B3LYP-D3-SMD(THF)/Def2SVP energies were corrected with zero-point energies and thermal corrections calculated at the B3LYP-D3/Def2SVP-SMD(THF) level of theory to obtain the Gibbs energy in the gas phase. 69…”

Section: Computational Detailsmentioning

confidence: 99%

A predictive chemistry DFT study of N₂O functionalization for the preparation of triazolopyridine and triazoloquinoline scaffolds

et al. 2022

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“…In the continuation of our research on Hal-based catalysts for hydrogenation reactions, [44][45][46][47] herein, and knowing that the presence of protic solvents and reagents is detrimental for this reaction, [48][49][50] we wish to report a combined computational and experimental study on the effect of the hydrophobicity of Hal on its performance for hydrofinishing of PAO.…”

Section: Introductionmentioning

confidence: 99%

Effect of support hydrophobicity of halloysite‐based catalysts on the polyalphaolefin hydrofinishing performance

Shams

Sadjadi

Duran

et al. 2022

Applied Organom Chemis

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Hydrogenation of polyalphaolefins (PAOs) is an industrial process catalyzed by supported precious metals. In this regard, halloysite (Hal) clay has been proven as an efficient support for the immobilization of Pd nanoparticles and development of high-performance catalysts under mild reaction condition. In this research, the effect of Hal hydrophobicity on the PAO hydrofinishing efficiency is studied. In this line, cetrimonium bromide (CTAB) was used for adjusting the hydrophobicity of halloysite surface. Three catalysts, Hal/Pd, Hal/Pd/CTAB, and Hal/CTAB/Pd, were fabricated by palladation of Hal, treating palladated Hal with CTAB and palladation of CTAB-treated Hal, respectively. The catalysts were characterized, and their activity for the hydrogenation of PAO was appraised. Moreover, a molecular simulation approach was employed to survey the effect of surface hydrophobicity of Hal on the alkene hydrogenation energy diagram and the steric maps of the main catalytic stages. Both experimental and computational studies approved that the presence of CTAB detracts the activity of the catalyst. Moreover, the order of introduction of Pd and CTAB affects the content of incorporated CTAB and Pd and Pd particle size, and the order of catalysts activity was as follows:

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Experimental and DFT study on titanium-based half-sandwich metallocene catalysts and their application for production of 1-hexene from ethylene

Cited by 12 publications

References 62 publications

Exploring cocatalyst type effect on the Ziegler–Natta catalyzed ethylene polymerizations: experimental and DFT studies

Exploring cocatalyst type effect on the Ziegler–Natta catalyzed ethylene polymerizations: experimental and DFT studies

A predictive chemistry DFT study of N₂O functionalization for the preparation of triazolopyridine and triazoloquinoline scaffolds

Effect of support hydrophobicity of halloysite‐based catalysts on the polyalphaolefin hydrofinishing performance

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Experimental and DFT study on titanium-based half-sandwich metallocene catalysts and their application for production of 1-hexene from ethylene

Cited by 12 publications

References 62 publications

Exploring cocatalyst type effect on the Ziegler–Natta catalyzed ethylene polymerizations: experimental and DFT studies

Exploring cocatalyst type effect on the Ziegler–Natta catalyzed ethylene polymerizations: experimental and DFT studies

A predictive chemistry DFT study of N2O functionalization for the preparation of triazolopyridine and triazoloquinoline scaffolds

Effect of support hydrophobicity of halloysite‐based catalysts on the polyalphaolefin hydrofinishing performance

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A predictive chemistry DFT study of N₂O functionalization for the preparation of triazolopyridine and triazoloquinoline scaffolds