Acidic and Catalytic Properties of Zeolites Modified by Zinc in the Conversion Process of Lower C3–C4 Alkanes

The acid and catalytic properties of the modified MFI zeolite catalysts during the conversion of the propane–butane fraction of the associated petroleum gases into the aromatic hydrocarbons were studied. It was established that the high-silica zeolites synthesized with the new structure-forming additive of the alcohol fraction (ZKE-AF) belong to the high-silica MFI zeolites. The resulting zeolites were modified by 1–5 wt. % additives consisting of zinc oxide and sulfide. The influence of the modifying additive concentration containing zinc oxides and sulfides in an amount of 1–5% on the acid and catalytic properties of the catalysts in the conversion process of lower C3–C4 alkanes into liquid hydrocarbons was studied. The research of the acid properties of the modified zeolite catalysts by thermal desorption of ammonia showed that the total concentrations of the acidic centers of H-ZKE-AF modified by 3% and 5% ZnO increased. It was found that the highest yield of liquid hydrocarbons was on the zeolite catalysts modified by 3% and 5% ZnS, and is 60.6% and 60.5%, respectively, which is 9% more than in the initial H-ZKE-AF. The activity of the zeolite catalysts modified by zinc oxide and zinc sulfide was in correlation with their acid properties.

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Linear Hexane Isomerization Over Bimetallic Zeolite Catalysts

Chemistry & Chemical Technology ◽

10.23939/chcht15.03.330 ◽

2021 ◽

Vol 15 (3) ◽

pp. 330-335

Author(s):

Lyubov Patrylak ◽

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Oleksandra Pertko ◽

Yuliya Voloshyna ◽

Angela Yakovenko ◽

...

Keyword(s):

Catalytic Properties ◽

Maximum Yield ◽

Nitrogen Adsorption ◽

Zeolite Catalysts ◽

Optimum Process ◽

Mfi Zeolite ◽

Hydrogen Form ◽

Alkane Isomerization ◽

Adsorption Desorption ◽

Palladium Content

The aim of this study was to evaluate the activity and selectivity in isomerization of n-hexane of bimetallic zeolite catalysts containing a nickel transition metal in addition to palladium. Bimetallic bifunctional linear alkane isomerization catalysts based on the hydrogen form of MFI zeolite have been synthesized. The porous properties of the samples were investigated by means of low-temperature nitrogen adsorption/desorption, the size of the metal component – by TEM, and the catalytic properties – in the micro-pulse isomerization of n-hexane. Antisymbatic correlation between the temperature of the maximum yield of hexane isomers and the amount of nickel in the sample was found for a stable palladium content. The introduction of nickel allows to reduce the optimum process temperature from 598 to 523 K.

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Conversion of the Propane–Butane Fraction into Arenes on MFI Zeolites Modified by Zinc Oxide and Activated by Low-Temperature Plasma

Molecules ◽

10.3390/molecules25112704 ◽

2020 ◽

Vol 25 (11) ◽

pp. 2704

Author(s):

Vladimir I. Erofeev ◽

Sofiya N. Dzhalilova ◽

Mikhail V. Erofeev ◽

Vasilii S. Ripenko ◽

Vladimir P. Reschetilowski

Keyword(s):

Aromatic Hydrocarbons ◽

Maximum Yield ◽

Acid Sites ◽

Zeolite Catalysts ◽

Silica Gels ◽

Mfi Zeolite ◽

Temperature Plasma ◽

High Silica ◽

Mfi Zeolites ◽

Propane Butane

The effect of modification of MFI zeolite 1–5 wt.% ZnO activated by plasma on acid and catalytic properties in the conversion of the propane–butane fraction into arenes was investigated. The high-silica zeolites with silicate module 45 were synthesized from alkaline alumina–silica gels in the presence of an ‘X-oil’ organic structure-forming additive. The modification of the zeolite with zinc was carried out by impregnating the zeolite granules in the H-form with an aqueous solution of Zn(NO3)2. The obtained zeolites were characterized by X-ray phase analysis and IR spectroscopy. It is shown that the synthesized zeolites belong to the high-silica MFI zeolites. The study of microporous zeolite-containing catalysts during the conversion of C3-C4 alkanes to aromatic hydrocarbons made it possible to establish that the highest yield of aromatic hydrocarbons is observed on zeolite catalysts modified with 1 and 3% ZnO and amount to 63.7 and 64.4% at 600 °C, respectively, which is 7.7–8.4% more than on the original zeolite. The preliminary activation of microporous zeolites modified with 1–5% ZnO and plasma leads to an increase in the yield of aromatic hydrocarbons from the propane–butane fraction; the maximum yield of arenes is observed in zeolite catalysts modified with 1 and 3% ZnO and activated by plasma, amounting to 64.9 and 65.5% at 600 °C, respectively, which is 8.9–9.5% more than on the initial zeolite. The activity of the zeolite catalysts modified by ZnO and activated by plasma show good agreement with their acid properties. Activation of the zeolites modified by 1 and 3% ZnO and plasma leads to an increase in the concentration of the weak acid sites of the catalyst to 707 and 764 mmol/g in comparison with plasma-inactivated 1 and 3% ZnO/ZKE-XM catalysts at 626 and 572 mmol/g, respectively.

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Selective Production of Aromatics from 2-Octanol on Zinc Ion-Exchanged MFI Zeolite Catalysts

Catalysts ◽

10.3390/catal5042122 ◽

2015 ◽

Vol 5 (4) ◽

pp. 2122-2133 ◽

Cited By ~ 2

Author(s):

Masakazu Iwamoto ◽

Ryota Takezawa ◽

Masao Morimoto

Keyword(s):

Zinc Ion ◽

Zeolite Catalysts ◽

Mfi Zeolite

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Preferred stability of aluminum-oxygen-silicon-oxygen-aluminum linkages in high-silica zeolite catalysts: theoretical predictions contrary to Dempsey's rule

The Journal of Physical Chemistry ◽

10.1021/j100127a003 ◽

1993 ◽

Vol 97 (25) ◽

pp. 6579-6581 ◽

Cited By ~ 35

Author(s):

Klaus Peter Schroeder ◽

Joachim Sauer

Keyword(s):

Zeolite Catalysts ◽

Theoretical Predictions ◽

High Silica ◽

Silicon Oxygen

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

REVIEWS ON ADVANCED MATERIALS SCIENCE ◽

10.1515/rams-2020-0037 ◽

2020 ◽

Vol 59 (1) ◽

pp. 188-206

Author(s):

Khashayar Sharifi ◽

Rouein Halladj ◽

Seyed Javid Royaee

Keyword(s):

Aromatic Compounds ◽

Zeolite Catalysts ◽

Adverse Impact ◽

General Knowledge ◽

Liquid Hydrocarbons

AbstractThe 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.

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Catalytic properties of ni kel-zeolite catalysts as a function of the state of the nickel in the reaction of benzene with ethylene

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science ◽

10.1007/bf00926395 ◽

1973 ◽

Vol 22 (11) ◽

pp. 2463-2468

Author(s):

Kh. M. Minachev ◽

Ya. I. Isakov ◽

G. V. Antoshin ◽

V. P. Kalinin ◽

E. S. Shpiro

Keyword(s):

Catalytic Properties ◽

The State ◽

Zeolite Catalysts

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Direct synthesis of high-silica nano ZSM-5 aggregates with controllable mesoporosity and enhanced catalytic properties

RSC Advances ◽

10.1039/c6ra21080e ◽

2016 ◽

Vol 6 (101) ◽

pp. 99129-99138 ◽

Cited By ~ 14

Author(s):

Hongyao Li ◽

Yaquan Wang ◽

Fanjun Meng ◽

Hengbao Chen ◽

Chao Sun ◽

...

Keyword(s):

Catalytic Properties ◽

Direct Synthesis ◽

High Silica

In the absence of additional mesoporous template, high-silica nano-sized ZSM-5 aggregates have been rapidly synthesized by solid-like state conversion.

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