An overview on the effects of metal promoters and acidity of ZSM-5 in performance of the aromatization of liquid hydrocarbons

Abstract

<jats:title>Abstract</jats:title><jats:p>The use of liquid hydrocarbons, such as FCC naphtha, having olefin components makes an adverse impact on our environment. To deal with the problem, one could convert those lethal components, including olefin and paraffin structures, into aromatic compounds under aromatization processes. To this aim, generally zeolite catalysts, especially the ZSM-5 sample, are utilized to facilitate the aromatization processes. According to the general knowledge in this field, such parameters as the metal promoter and the amount of acidity of catalyst affect the performance of zeolite catalysts. In this paper, with the aim of getting acquainted with the conditions to form the desirable products under the best performance of the zeolites, numerous published papers were reviewed.</jats:p>

Hydrocracking optimization of palm oil to bio-gasoline and bio-aviation fuels using molybdenum nitride-bentonite catalyst

“… 68 The highest catalyst acidity of 0.13 mmol g −1 was achieved by MoN-bentonite 8 mEq g −1 . The acidity of the catalyst greatly affected the hydrocracking process of the oil, 69 in which a higher amount of acidity was associated with more active sites and a greater adsorption capacity of the reactants. 70 Hence, a high acidity of catalysts would provide more conversion of palm oil into biofuels.…”

Selective Valorization of CO2 towards Valuable Hydrocarbons through Methanol‐mediated Tandem Catalysis

“…BAS density of zeolite can also be modulated to reduce catalyst deactivation. Apart from changing the Si/Al ratio, other alternative techniques include metal impregnation, [148–150] treatment with reagents such as silicon tetrachloride, tetraethyl orthosilicate, and tetramethyl orthosilicate to suppress the external acidity, [8] and higher calcination temperatures to convert BAS to Lewis acid sites [148] . These methods have the potential to reduce BAS density and minimize zeolite deactivation [148–150] …”

“…[148] These methods have the potential to reduce BAS density and minimize zeolite deactivation. [148][149][150] The deactivation of zeolite could further be avoided by encapsulation. For instance, an acidic ZSM-5 zeolite was encapsulated with an ultrathin protective shell of silicalite-1 zeolite that passivated the surface of the acidic zeolite.…”

Nanoreactor Engineering Can Unlock New Possibilities for CO2 Tandem Catalytic Conversion to CC Coupled Products

“…As explained in the studies, the stronger Brønsted acidity of H‐ZSM‐5 supports the aromatization reaction, while the weaker acidity of H‐beta or H‐MCM‐22 supports the isomerization reaction. [ 161 , 162 ] The content of the final product can be adjusted by adjusting the acid strength and pore size of the zeolites. Oxygen cavities on the surface of In 2 O 3 are proposed to activate CO 2 and hydrogen, resulting in the formation of methanol.…”