Tuning the Brønsted and Lewis acid nature in HZSM-5 zeolites by the generation of intracrystalline mesoporosity—Catalytic behavior for the acylation of anisole

Silva, Domingos S. Araújo; Castelblanco, William N.; Piva, D.H.; Macedo, Vinícius de; Carvalho, Kele T. G.; Urquieta‐González, Ernesto A.

doi:10.1016/j.mcat.2020.111026

Cited by 14 publications

(4 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Particularly, the strong acid sites, which are mainly Brønsted acids promote the undesired coke formation, because the coke deposits preferentially on these sites through different proton transfer steps that occur on the Brønsted acid sites [26]. It is important to mention that understanding of acidity types of the zeolite catalyst can be appreciated from the Si/Al ratio [44]. Tuning of the acid strength [41] and reduction in the acid density [45] are two notable strategies to reduce coke deposits.…”

Section: Effect Of Catalyst Aciditymentioning

confidence: 99%

“…These techniques are deployed to stabilize the zeolite and achieve higher selectivity of BTX. Conducted studies have evidenced that most strategies used to achieve dealumination or functionalization with metals are invasive, i.e., the crystallinity is sometimes affected significantly [44]. Hence, it is pertinent to look for non-invasive methods, such as low-temperature plasma techniques and isomorphous substitution methods [46,48].…”

Section: Prospects Of Catalytic Glycerol To Bio-aromaticsmentioning

confidence: 99%

See 1 more Smart Citation

Catalytic Conversion of Glycerol to Bio-Based Aromatics

Okoye¹,

Duque-Brito²,

Lobata-Peralta³

et al. 2023

Ethanol and Glycerol Chemistry - Production, Modelling, Applications, and Technological Aspects

View full text Add to dashboard Cite

Green application of biodiesel-derived glycerol will boost biodiesel production in terms of sustainability and economics. The glycerol to liquid fuels is a promising route that provides an additional energy source, which contributes significantly to energy transition besides biodiesel. This pathway could generate alkyl-aromatic hydrocarbons with a yield of ∼60%, oxygenates, and gases. MFI Zeolites (H-ZSM-5) catalysts are mainly used to propagate the aromatization pathway. This chapter presents the pathways, challenges, catalytic design, influences of catalyst acidity, metal addition, reaction condition, and catalysts deactivation on glycerol conversion to hydrocarbon fuels and aromatics. Studies revealed that time on stream, temperature, and weight hourly space velocity (range of 0.1–1 h−1) influences the benzene, toluene, and xylene BTX and benzene, toluene, ethylbenzene, and xylene BTEX yield. Acidity of the H-ZSM-5 could be tailored by metals, additives, and binders. Bronsted acidity promotes coke formation which results in reversible deactivation of the H-ZSM-5 catalyst. It is hoped that this study will promote intensified research on the use of glycerol for purposes of fuel generating and valuable products.

show abstract

Section: Effect Of Catalyst Aciditymentioning

confidence: 99%

Section: Prospects Of Catalytic Glycerol To Bio-aromaticsmentioning

confidence: 99%

Catalytic Conversion of Glycerol to Bio-Based Aromatics

Okoye¹,

Duque-Brito²,

Lobata-Peralta³

et al. 2023

Ethanol and Glycerol Chemistry - Production, Modelling, Applications, and Technological Aspects

View full text Add to dashboard Cite

show abstract

“…However, there are some serious limitations in these conventional homogeneous Lewis acid catalysis processes with respect to environmental concerns and resource utilization, mainly arising from the disposal of the huge amount of metal halides and toxic wastes. In order to meet the demands of green chemical industry, recent efforts have been devoted to exploring heterogeneous acylation catalysts, including supported heteropolyacid [4][5][6], solid superacid [7], carbon-based metal oxides [8,9], and zeolites [10][11][12][13][14][15][16][17][18][19][20].…”

Section: Introductionmentioning

confidence: 99%

Micron-Sized Hierarchical Beta Zeolites Templated by Mesoscale Cationic Polymers as Robust Catalysts for Acylation of Anisole with Acetic Anhydride

Miao,

Sun,

Lei

et al. 2023

Catalysts

View full text Add to dashboard Cite

Hierarchical Beta zeolites with interconnected intracrystalline mesopores and high structural stability are highly attractive for catalytic applications involving bulky reactants. Here, by introducing a suitable amount of polydiallyldimethylammonium chloride into the initial synthesis system, micron-sized Beta zeolite crystals with abundant hierarchical porosity (Beta-H) were hydrothermally synthesized. The sample named Beta-H_1 exhibited very high catalytic activity and durability for the Friedel–Crafts acylation of anisole with acetic anhydride. A 92% conversion rate of acetic anhydride could be achieved after 1 h of reaction in a fixed bed reactor, and 71% conversion still remained after 10 h, much better than the rate for conventional Beta zeolite (which decreased rapidly from 85% to 37% within 10 h). The enhanced catalytic performance of Beta-H zeolites could be mainly attributed to the relatively lower strong acid density and the faster transport rate of the hierarchical zeolites. In addition, Beta-H showed high structural stability and could be easily regenerated via high-temperature calcination without obvious loss in catalytic activity, demonstrating its great potential for catalytic applications in the industrially important Friedel–Crafts acylation process.

show abstract

“…Due to their versatile porous architectures, such as pores, cages, channels, zeolites can accommodate chemical species with different sizes and shapes for catalytic purposes. Strong Brønsted and Lewis acidity with tunable activity and locality allows spontaneous catalysis to take place on the zeolite surface or inside the porous regimes. − Diffusion of reactants and products inside the porous structure is a key property to consider while designing a catalytic system. Transport of reactants and products are often the rate-limiting step in a chemical transformation process.…”

Section: Introductionmentioning

confidence: 99%

Insights into Sorption and Molecular Transport of Aqueous Glucose into Zeolite Nanopores

et al. 2022

View full text Add to dashboard Cite

Liquid-phase heterogeneous catalysis using zeolites is important for biomass conversion to fuels and chemicals. There is a substantial body of work on gas-phase sorption in zeolites with different topologies; however, studies investigating the diffusion of complex molecules in liquid medium into zeolitic nanopores are scarce. Here, we present a molecular dynamics study to understand the sorption and diffusion of aqueous β-d-glucose into β-zeolite silicate at T = 395 K and P = 1 bar. Through 2-μs-long molecular dynamics trajectories, we reveal the role of the solvent, the kinetics of the pore filling, and the effect of the water model on these properties. We find that the glucose and water loading is a function of the initial glucose concentration. Although the glucose concentration increases monotonically with the initial glucose concentration, the water loading exhibits a nonmonotonic behavior. At the highest initial concentration (∼20 wt %), we find that the equilibrium loading of glucose is approximately five molecules per unit cell and displays a weak dependence on the water model. Glucose molecules follow a single-file diffusion in the nanopores due to confinement. The dynamics of glucose and water molecules slows significantly at the interface. The average residence time for glucose molecules is an order of magnitude larger than that in the bulk solution, while it is about twice as large for the water molecules. Our simulations reveal critical molecular details of the glucose molecule’s local environment inside the zeolite pore relevant to catalytic conversion of biomass to valuable chemicals.

show abstract

Tuning the Brønsted and Lewis acid nature in HZSM-5 zeolites by the generation of intracrystalline mesoporosity—Catalytic behavior for the acylation of anisole

Cited by 14 publications

References 72 publications

Catalytic Conversion of Glycerol to Bio-Based Aromatics

Catalytic Conversion of Glycerol to Bio-Based Aromatics

Micron-Sized Hierarchical Beta Zeolites Templated by Mesoscale Cationic Polymers as Robust Catalysts for Acylation of Anisole with Acetic Anhydride

Insights into Sorption and Molecular Transport of Aqueous Glucose into Zeolite Nanopores

Contact Info

Product

Resources

About