Direct Synthesis of Nano‐Ferrierite along the 10‐Ring‐Channel Direction Boosts Their Catalytic Behavior

Abstract

Ferrierite zeolites with nanosized crystals and external surface areas higher than 250 m g have been prepared at relatively low synthesis temperature (120 °C) by means of the collaborative effect of two organic structure directing agents (OSDA). In this way, hierarchical porosity is achieved without the use of post-synthesis treatments that usually involve leaching of T atoms and solid loss. Adjusting the synthesis conditions it is possible to decrease the crystallite size in the directions of the 8- and 10-ring channels, [010] and [001] respectively, reducing their average pore length to 10-30 nm and increasing the number of pores accessible. The small crystal size of the nano-ferrierites results in an improved accessibility of reactants to the catalytic active centers and enhanced product diffusion, leading to higher conversion and selectivity with lower deactivation rates for the oligomerization of 1-pentene into longer-chain olefins.

State of the Art and Perspectives of Hierarchical Zeolites: Practical Overview of Synthesis Methods and Use in Catalysis

“…Ferrierite shows a good thermal, hydrothermal, and chemical stability and is currently used in many applications such as the hydroisomerization of n-alkanes, isomerization of n-alkenes, cracking of n-paraffins, NO x reduction, styrene epoxidation, N 2 O decomposition, etc. [47][48][49] The main industrial application of ferrierite is the isomerization of 1-butene. [50] Top-Down Methods-Dealumination/Desilication: Dealumination and desilication have been reported multiple times to introduce mesopores in ferrierite.…”

“…This nanocatalyst showed a very high 1-pentene oligomerization activity with high diesel selectivity and a longer life time, explained by the short diffusion path lengths in the zeolite crystals. [48] Finally, Wuamprakhon et al assembled nanosheets of ferrierite into a ball-shaped morphology during a direct hydrothermal synthesis in the presence of dimethyloctadecyl [3-(trimethoxysilyl)propyl]ammonium chloride (TPOAC) as SDA. As such, a hierarchical ferrierite system with high crystallinity and microporosity was acquired.…”

Advances in the Synthesis of Ferrierite Zeolite

“…Zeolites are crystalline microporous materials which have been widely applied on an industrial scale in heterogeneous catalysis, adsorption, separation and ion exchange in the past decades [ 1 , 2 , 3 , 4 , 5 ]. Among them, Ferrierite (FER) zeolite is one of the industrialized types, which has excellent catalytic properties in skeletal isomerization of n-alkene, methanol to olefin, N 2 O decomposition, CO 2 hydrogenation, dehydration of methanol or ethanol, dimethyl ether carbonylation, and so on [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ].…”

Computational Modeling of Open Framework Silicates: Probing Straight Bond Angles in Ferrierite Reveals Intriguing Links Between Mineralogy, Nanomaterial Science and Technological Applications

“…Natural FER is an aluminosilicate zeolite generally found both in volcanic and sedimentary rocks, often coexisting with other minerals (zeolites, silica polymorphs, carbonates) (Yokomori et al 2001). By judiciously tuning the process parameters, it can also be synthesized via hydrothermal routes with desired Al/Si ratio (Guo et al 2000;Cheng et al 2006), hierarchical porosity (Xue et al 2015) and in nanostructured form (Margarit et al 2018). At relatively mild temperatures, ferrierites with high Si/Al ratio and Bronsted acid sites are excellent and highly selective catalysts for alkene isomerization and cracking -another essential process in petrochemical industry (Corma 2003;de Ménorval et al 2005;Čejka et al 2012;Wiedemann et al 2016) -as well as for low-density polyethylene pyrolysis, which allows for the green conversion of plastic waste into valuable fuels (Bonilla et al 2009).…”