Ethylbenzene Selectivity Research Articles

Efficient ethylbenzene production from CO2 and benzene in a single-bed reactor

The selective synthesis of specific value-added aromatic hydrocarbons through CO2 hydrogenation holds significant strategic importance in mitigating energy and climate issues. However, the process of forming ethylated side chains on benzene rings is challenging, and the methods reported are often limited by multi-bed systems. Here, we show the first CO2 hydrogenation in tandem coupling with benzene alkylation to synthesize ethylbenzene over a single-bed system containing ZnFeOx and nano ZSM-5 catalysts. The results indicated that the bifunctional catalyst composed of ZnFeOx with a Zn/Fe ratio of 0.5 and nano-HZSM-5 exhibits excellent catalytic performance under optimized conditions. The benzene conversion reaches 28.0 %, ethylbenzene selectivity is 61.3 % and the conversion of CO2 is remarkably high, achieving 45.0 %. This single-bed system significantly promotes the in-situ utilization of ethylation intermediates. The introduction of zinc promoted the formation of ZnFe2O4 spinel, which increased the number of active sites due to its superior dispersibility and reducibility. Nano-HZSM-5 demonstrated outstanding ethylbenzene selectivity and catalytic stability owing to its unique shape selectivity, moderate acidity, and superior diffusion properties. This study further explores the reaction network and mechanism through GC–MS analysis and various model reactions, elucidating the formation pathways of primary products in detail. This research provides a new strategy for the controllable synthesis of ethylbenzene using CO2 as a C1 source in a single-bed system.

Controllable interlayer hydroxyl condensation of MWW zeolite and its alkylation performance of benzene with ethylene

MWW zeolite holds great promise in the petrochemical industry. However, achieving precise control over its dimension and interlayer hydroxyl condensation remains challenging when using a single, low-toxicity, readily available template. In this study, the rational and targeted hydrothermal synthesis of two-dimensional (2D) MCM-22(P) and three-dimensional (3D) MCM-49 using low-toxic piperidine is realized. The synergistic effect of the organic template and inorganic ions plays a crucial role in the precise synthesis of 2D and 3D MWW zeolite. In contrast to the traditional hexamethyleneimine template, piperidine introduces a distinct characteristic whereby disordered MWW layers coexist with the synthesized products. Specifically, the higher concentration of Na+ species directs more Al species to locate in the T1 site, promoting the condensation of interlayer hydroxyl and leading to the formation of 3D MWW zeolite. In contrast, a system with abundant PI can suppress the condensation of interlayer hydroxyl, resulting in the formation of 2D MWW zeolite. H-MCM-49 synthesized exhibits higher ethylene conversion and ethylbenzene selectivity than H-MCM-22 in the liquid alkylation of benzene and ethylene.

Insight into the competitive adsorption mechanism of ethylbenzene and octane on zeolite NaY with different SAR

The Si/Al molar ratio (SAR) of zeolites is crucial for separating unsaturated hydrocarbon components, but it was difficult to rule out the impact of changes in pore properties. In this work, a GCMC method was developed to investigate the effect of varying SAR (2.4, 20, and 50) using a module of NaY zeolite. The deviation of pore properties is less than 5%. When using ethylbenzene and n-octane as probe molecules, increasing the SAR is not conducive to improving the selectivity of ethylbenzene in single component adsorption, but in the two components, the selectivity increases from 76.0% to 92.6% when SAR increasing from 2.4 to 50. The increase of diffusion coefficient in two component is also significantly different. The NH3 radial distribution functions (RDF) method was used to investigate the number of acid sites and acid strength, it can be observed that the adsorption capacity of ammonia decreases with SAR increasing but slightly when the SAR exceed 50. However, the number of ammonia molecules adsorbed per site significantly increases, the II site exhibits stronger acidity than III site. To distinguish different preferences of adsorbate onto zeolites with different SAR, concentration distribution combined with RDF was used. During single-component adsorption, both ethylbenzene and n-octane could be freely adsorbed on the II and III sites, however in binary situation, ethylbenzene tended on the II sites, while n-octane on the III sites. As the SAR increased, the adsorption of ethylbenzene, which displaced the original adsorption sites occupied by n-octane and consequently improved the selectivity of ethylbenzene. To investigate the interaction between adsorbents with different polarities, different feed concentration and RDF between the adsorbates were used, which revealed that polarities may have a greater impact on selectivity. Through the Monte Carlo series of tools, the structure-performance relationship between complex adsorbates and adsorbed molecules can be studied clearly.

Iridium Nanoparticles on SPIONs as a Catalyst for N‐Heteroarene and Styrene Hydrogenation Reactions and their DFT Studies

AbstractIn this study, iridium nanoparticles (IrNPs) on superparamagnetic iron oxide nanoparticles (SPIONs) are used to catalyze N‐heteroarene and styrene hydrogenation processes. The IrNP@SPIONs catalyst was fabricated by reducing the Ir‐salt precursors in deionized water on SPIONs (Fe3O4), and its catalytic reactivity for the hydrogenation of N‐heteroarenes and styrene under mild reaction conditions as hydrogen under pressure was evaluated. The catalyst was characterized by FTIR, Raman, XRD, SEM, XPS, ICP‐OES, and TEM. The results showed that IrNPs@SPIONs exhibited >99 % conversion with 1,2,3,4‐tetrahydroquinoline (py‐THQ) selectivity under 30 bar H2 at 100 °C temperature in 24 h using DCM as a solvent. The functional group tolerance of 6‐chloroquinoline demonstrated 99 % chemoselectivity towards the 6‐chloro‐tetrahydroquinoline (6‐Cl‐py‐THQ) formation. The reactivity trend in 2‐, 4‐, and 8‐methylquinoline was evaluated and corroborated with the DFT studies. The catalytic application was extended to the hydrogenation of styrene, which resulted in a 70 % conversion with >99 % ethylbenzene selectivity. The hydrogenation of 2‐bromostyrene produced a 75 % conversion with >99 % chemoselectivity of 2‐bromoethylbenzene.

Machine learning-driven prediction and optimization of monoaromatic oil production from catalytic co-pyrolysis of biomass and plastic wastes

Catalytic co-pyrolysis of biomass and plastic wastes is an efficient way for monoaromatic-rich oil production, while it is difficult to conclude oil evolution rule due to the complex interaction of multiple factors during co-pyrolysis. Hence, multiple machine learning algorithms were devised to aid process optimization and zeolite catalyst screening. The results showed that gradient boosting decision tree model performed the best prediction accuracy and generalization ability, as its coefficient of determination (R2) and root-mean-square error were 0.90 and 5.04, compared to random forest (R2 ∼ 0.84), extreme gradient boosting (R2 ∼ 0.90), and light gradient boosting machine (R2 ∼ 0.86). Both feature importance and partial dependence analysis showed that operating parameters, catalyst properties, and feedstock composition were in the descending order to affect oil yield with monoaromatic selectivity. The reaction temperature (∼500 °C) and feedstock/catalyst ratio (<5:1) had preferable influence on higher oil yield. The optimal selectivity of benzene, toluene, ethylbenzene and xylene (BTEXs) in oil would be obtained at plastic proportion of around 60 wt% and Si/Al ratio of 20–30. The two-way PDA about interaction effect between multiple factors for oil products were also discussed in detail. The work favors to rationalize large-scale oil production from pyrolysis of solid wastes.

B-Axis-Oriented ZSM-5 Nanosheets for Efficient Alkylation of Benzene with Methanol: Synergy of Acid Sites and Diffusion

ZSM-5 nanosheets are promising catalysts for the catalytic reactions controlled by diffusion limitations. This study reveals its significant application in the alkylation of benzene with methanol. The b-axis-oriented ZSM-5 nanosheets with similar acid property but varied thicknesses of about 30, 90, and 300 nm were prepared to investigate the effect of thickness on their catalytic properties for alkylation reactions. Comparative results demonstrate that the sample with a thickness of 30 nm exhibits higher benzene conversion, xylene selectivity, and methyl selectivity (up to 97%), accompanied by an ultralong lifetime (up to 1000 h, 10 times longer than that of the sample with a thickness of 300 nm) and lower byproduct ethylbenzene selectivity. This is ascribed to the shortened straight channel length, increased specific surface area, and enlarged mesopore volume that significantly facilitate the diffusion of reactants and products, increase the accessibility of acid sites, and decrease the coke formation. Moreover, compared with conventional ZSM-5 nanocrystals, ZSM-5 nanosheets deliver a substantially extended lifetime due to fewer framework defects. Most significantly, this study unravels the diffusion effect on ethylbenzene selectivity over ZSM-5 nanosheets with different thicknesses and illustrates the role of strong Brønsted acid sites in the dynamic changes of ethylbenzene selectivity. In light of the above analysis, we developed a precoking strategy and an introducing-heteroatom strategy to precisely tailor the catalyst acidity, further suppressing the ethylbenzene formation (<0.3%) while maintaining long-term stable operation (>300 h).

Synergetic and efficient alkylation of benzene with ethane over Pt/ZSM-5 nanosheet bifunctional catalysts to ethylbenzene

Alkylating benzene with ethane is advantageous but more challenging than the conventional alkylation with ethylene. The present work explored rational design of Pt/ZSM-5 bifunctional catalysts for alkylating benzene with ethane to produce ethylbenzene. Here, two series of ZSM-5 nanosheets with different b-axis thicknesses (30 ∼ 400 nm) and varied Si/Al ratio (10 ∼ 100) were synthesized for preparing Pt/ZSM-5 catalysts. The catalytic performance (conversion of ethane and benzene, EB selectivity) of these catalysts was evaluated in direct alkylation of benzene with ethane. As expected, Pt/ZSM-5 with smallest average nanosheet thickness delivers the highest ethylbenzene yield (the yield with 30 nm nanosheet is ∼1.5 times that with 400 nm nanosheet), attributed to its high accessibility to acid sites and favourable diffusion condition. Most significantly, this study reveals that the Si/Al ratio of ZSM-5 regulates the dispersion and particle size of Pt of Pt/ZSM-5. With same Pt loading, the Pt/ZSM-5 catalyst with a lower Si/Al ratio exhibits a higher Pt dispersion and smaller particle size. This is attributed to the interaction between H+ of ZSM-5 and Pt. The interaction not only has the anchoring effect for Pt (thus enhances the Pt dispersion on ZSM-5 and limits the Pt particle size), but also weakens the acid strength. These two effects work interactively in controlling the product distribution and accompanied side reactions in alkylation of benzene with ethane. When optimized, at ultralow Pt loading of 0.05 wt%, Si/Al of 30 and ZSM-5 nanosheet thickness of 30 nm, the Pt/ZSM-5 catalyst delivers high ethylbenzene selectivity and yield with stability and completely suppresses the methane selectivity.

BTEX sensing potential of elemental-doped graphene: a DFT study.

Elementally-doped graphene demonstrates remarkable gas sensing capabilities as a novel 2D sensor material. In this study, we employed density functional theory calculations, we investigated the impact of various dopants on the BTEX (benzene, toluene, ethylbenzene, and xylene) sensing performance of graphene. Through the systematic analysis of electronic structures and sensitivity, we observed that both the doping method and dopant type significantly influence the interactions between graphene and BTEX molecules. Out of the 22 different elemental doped graphenes studied, N-, O-, and Pd-doped graphenes emerged as promising candidates for BTEX sensor materials. Graphene with N-doping exhibited relatively higher sensitivity towards toluene, ethylbenzene, and xylene compared to O- and Pd-doped graphenes. However, it demonstrated low sensitivity towards benzene. On the other hand, O-doped graphene displayed excellent selectivity for ethylbenzene over the other three gas molecules (benzene, toluene, and xylene). Similarly, Pd-doped graphene also exhibited significant selectivity for ethylbenzene and possessed higher sensitivity than the O-doped graphene. Their distinct characteristics and sensitivities make them potential candidates for future applications in gas sensing technology.

Stabilization of Extra-Large-Pore Zeolite by Boron Substitution for the Production of Commercially Applicable Catalysts.

Stable extra-large-pore zeolites are desirable for industrial purposes due to their ability to accommodate bulky reactants and diffusion through channels. Although there are several extra-large pore zeolites reported, stable ones are rare. Thus, their stabilization is a feasible strategy for industrial applications. Here, an extra-large-pore zeolite EWT with boron substitution is presented, and the resulting zeolite B-RZM-3 increased the thermal stability from 600 °C in its silica form to 850 °C. The crystal structure, determined by combining continuous rotation electron diffraction (cRED) and powder X-ray diffraction (PXRD), shows that B atoms preferentially substitute the interrupted (HO)T(OT)3 (Q3 ) sites and are partially converted into 3-coordination to relax framework deformation upon heating. After Al-reinsertion post-treatment, Al-B-RZM-3 shows higher ethylbenzene selectivity and ethylene conversion rate per mol acid site than commercial ZSM-5 and Beta zeolite in benzene alkylation reaction. Synthesizing extra-large-pore zeolite in borosilicate form is a potential approach to stabilize interrupted zeolites for commercial applications.

Dual-template synthesis of thinner-layered MCM-49 zeolite to boost its alkylation performance

MCM-49 zeolite has MWW toplological structure similar to MCM-22 and it possesses connatural more external acid sites, performing more advantages in solid acid catalysis. Herein, a thinner-layered C18-MCM-49 microsphere by using diquaternary ammonium salts (C18–6–6Br2, denoted as C18, or Cn6n series) in mixture sols was achieved. This C18-MCM-49 microsphere possesses a 1–2 µm particle size, for which the crystal sheets decrease to ∼200 nm in size and 5–20 nm in thickness, which originated from that more C18 molecules located in the half cups and supercages pores to achieve the separation of MWW layer thickness in the c direction. The C18-MCM-49 zeolite provides an ultra-large external surface area (212 m2•g−1) and mesopore volume (0.767 cm3•g−1), and compared with traditional MCM-49 (Sext = 133 m2•g−1, Vmes = 0.414 cm3•g−1), external surface area and mesopore volume were increased by 59.4% and 85.3%, respectively. Due to its thinner-layered structure, this C18-MCM-49 microsphere displays more active acid sites on the external surface, leading to an improved ethylbenzene selectivity (94.7%) and benzene conversion (34%) in alkylation reaction. By using synchrotron radiation Small-angle X-ray scattering, we further studied series of synthetic sols during aging period. The results prove the behavior of aluminosilicate species in the mixture plays critical role in thinner-layered MCM-49, specifically, the precursor fractal between 2 and 2.5 is a key factor in synthesizing MCM-49. Collectively, this result offers a convenient and valid way to synthesize other types of zeolites.

Production of aromatics from butanol over Ga-promoted HZSM5 catalysts: tuning of benzene–toluene–xylene and ethylbenzene (BTEX) selectivity

The present investigation demonstrates the conversion of n-butanol to aromatics (BTA) including building block aromatics over Ga modified HZSM5 catalysts in a fixed bed reactor under varying process parameters (temperature, pressure, and WHSV).

Three-phase modeling and optimization of benzene alkylation in commercial catalytic reactors

Abstract The main object of this research is heterogenous modeling of benzene alkylation in three phase reactors based on the mass and energy balance equations by coupling the kinetic and equilibrium models and optimization the process conditions to enhance production capacity. In the first step, the alkylation reactors are simulated considering a three-phase model including heat and mass transfer resistances in the solid catalyst, gas and liquid phases. To prove the accuracy of developed model and adopted assumptions, the simulation results are compared with the plant data. Based on the simulation results, the benzene conversion and ethylbenzene selectivity in the alkylation reactors are 15.03 and 94.60% at the conventional condition. In the second step, considering the temperature of inlet streams to the reactors as decision variables, an optimization problem is formulated to maximize the ethylbenzene production rate as the objective function. Based on the simulation results, applying optimal condition on the system improves the ethylbenzene production by 1.33% at the same ethylene conversion compared to the conventional condition.

“Desert Rose” MCM-22 microsphere: Synthesis, formation mechanism and alkylation performance

A “Desert Rose” MCM-22 microsphere is achieved by combination of a gemini quaternary ammonium (C18-6-6 or C6-6-6) surfactant in HMI growth mixture. This specific MCM-22 microsphere appears about 2 μm in diameter, which is vortically assembled by hexagonal nanosheets with 200 nm long and 5–20 nm thick. The synergistic effect between C6-6-6/C18-6-6 and HMI is significant for controlling the flakelet crystal growth and forming the desert rose-like shaped morphology. This work focuses on fundamental nucleation and crystallization of zeolites, especially, the effect of C18-6-6/C6-6-6 on the structural morphology and properties. Typically, C6-6-6 preferentially interacts with aluminosilicate species, allowing slow depolymerization of silicon species and crystal nucleation, and promoting exfoliation of the interlayer by connecting with Al site on the surface. This rose-like shaped MCM-22 zeolite exhibits high benzene conversion (30–32%) and ethylbenzene selectivity (~90%) in the reaction of benzene and ethylene, which should be attributed to its lamellar structure with large surface area and mesoporous property, exposing more accessible acid sites than conventional MCM-22. Above all, our findings demonstrate a facile and effective route to directly synthesize thinner MWW-type materials, which may prove to be more broadly applicable to other layered zeolites.

Effect of relative percentage of acid and base sites on the side-chain alkylation of toluene with methanol.

K3PO4/NaX catalysts were prepared by loading potassium phosphate on NaX zeolite, and the catalytic performance was studied for the side-chain alkylation of toluene with methanol to styrene and ethylbenzene. Combined with the characterization of XRD, TPD-NH3, TPD-CO2, and FTIR and the determination of phosphorus content, it is revealed that firstly, the P element loaded on the catalyst surface can prominently promote the percentage of middle base sites, which will accordingly enhance the selectivity of the products (styrene and ethylbenzene) of side-chain alkylation of toluene; secondly, if there are enough middle base sites distributed on the catalysts, the higher percentage of strong base sites benefit the selectivity of styrene, which is confirmed by the performance of the two-stage catalysts.

Realizing Catalytic Acetophenone Hydrodeoxygenation with Palladium-Equipped Porous Organic Polymers.

Porous organic polymers (POPs) constructed through covalent bonds have raised tremendous research interest because of their suitability to develop robust catalysts and their successful production with improved efficiency. In this work, we have designed and explored the properties and catalytic activity of a template-free-constructed, hydroxy (-OH) group-enriched porous organic polymer (Ph-POP) bearing functional Pd nanoparticles (Pd-NPs) by one-pot condensation of phloroglucinol (1,3,5-trihydroxybenzene) and terephthalaldehyde followed by solid-phase reduction with H2. The encapsulated Pd-NPs rested within well-defined POP nanocages and remained undisturbed from aggregation and leaching. This polymer hybrid nanocage Pd@Ph-POP is found to enable efficient liquid-phase hydrodeoxygenation (HDO) of acetophenone (AP) with high selectivity (99%) of ethylbenzene (EB) and better activity than its Pd@Al2O3 counterpart. Our investigation demonstrates a facile, scalable, catalyst-template-free methodology for developing novel porous organic polymer catalysts and next-generation efficient greener chemical processes from platform molecules to produce value-added chemicals. With the aid of comprehensive in situ ATR-IR spectroscopy experiments, it is suggested that EB can be more easily desorbed in a solution, reflecting from the much weaker but better-resolved signal at 1494 cm-1 in Pd@Ph-POP compared to that in Pd@Al2O3, which is the key determining factor in favoring an efficient catalytic mechanism. Density functional theory (DFT) calculations were performed to illustrate the detailed reaction network and explain the high catalytic activity observed for the fabricated Pd@Ph-POP catalyst in the HDO conversion of AP to EB. All of the hydrogenation routes, including direct hydrogenation by surface hydrogen, hydrogen transfer, and the keto-enol pathway, are evaluated, providing insights into the experimental observations. The presence of phenolic hydroxyl groups in the Ph-POP frame structure facilitates the hydrogen-shuttling mechanism for dehydration from the intermediate phenylethanol, which was identified as a crucial step for the formation of the final product ethylbenzene. Besides, weaker binding of the desired product ethylbenzene and lower coverage of surface hydrogen atoms on Pd@Ph-POP both contributed to inhibiting the overhydrogenation reaction and explained well the high yield of EB produced during the HDO conversion of AP on Pd@Ph-POP in this study.

Synthesis of a Zeolite-Containing Catalyst for Gas-Phase Alkylation of Benzene with Ethylene

A multistage synthesis of the catalyst for the gas-phase alkylation of benzene with ethylene is implemented. A highly active catalyst is synthesized from zeolite ZSM-5 using thermal-vapor treatment. The obtained catalyst possesses an optimal acidity, which makes it possible to achieve a higher yield of ethylbenzene compared to the commercial catalyst based on ZSM-5 (88 and 62.7 wt %, respectively), an approximately equal ethylbenzene selectivity, and an almost three times lower concentration of the undesirable xylene impurity in an alkylate (0.004 and 0.011 wt %, respectively) in the gas-phase benzene alkylation with ethylene.

The Influence of Modification on the Properties of High-Silica TsVM Zeolite in the Benzene Alkylation Reaction with Ethanol

The influence of the nature of a modifying metal (Sc, La, Gd, Yb) on the physicochemical and catalytic properties of a high-silica zeolite of the TsVM type in the alkylation reaction of benzene with ethanol has been studied in a plug-flow- reactor unit in the temperature range of 350–450°C. It has been found that the activity and selectivity of the catalyst depend on the nature of the modifying metal. The maximum yield of ethylbenzene is achieved over the Yb-loaded zeolite to be 40.7 wt % with the selectivity of 56.1%. The modified catalysts are ranked as follows with respect to the yield of ethylbenzene: Yb–HTsVM > La–HTsVM > Gd–HTsVM > Sc–TsVM. The highest ethylbenzene selectivity (59.5%) is obtained on the La-promoted zeolite. The modified catalysts are arranged as follows with respect to the ethylbenzene selectivity: La–HTsVM > Gd–HTsVM > Yb–HTsVM > Sc–HTsVM. There are substantial of amounts xylenes and di- and triethylbenzenes formed in the presence of Sc–HTsVM, leading to a decrease in the ethylbenzene selectivity. As opposed to other modifiers, the micropore volume and average pore diameter of the zeolite increase in the case of modification by Sc. It has been found that the increase in the ethylbenzene selectivity of the catalysts modified with La, Gd, and Yb is associated with the nature of the modifying metal, a decrease in the strength and concentration of strong acid sites, and a decrease in the specific surface area and total pore volume of the zeolite as a result of its chemical modification.

Characteristics of the catalytic fast pyrolysis of vegetable oil soapstock for hydrocarbon-rich fuel

Hydrocarbon-rich fuel from vegetable oil soapstock is potentially a good alternative to conventional fossil-derived fuels. This paper reported on pyrolysis experiments with compounds including vegetable oil soapstock, sodium stearate(C18), sodium palmitate(C16), sodium oleate(C18:1), and sodium linoleate(C18:2). The effects of pyrolysis temperature, HZSM-5 catalyst, unsaturation degree and carbon chain length on the formation of aromatic hydrocarbons were explored. Experimental results indicated that the relative content of oxygenated compounds significantly decreased in the condensable organic compounds of soapstock pyrolysis, and aromatic hydrocarbons increased when the HZSM-5 catalyst was used, in which toluene and xylene had the highest relative selectivity. High catalytic pyrolysis temperature was beneficial to the relative selectivity of benzene and toluene, but inhibited the relative selectivity of xylene and ethylbenzene. The increase in saturation of fatty acid salts promoted the reaction toward the production of polycyclic aromatic hydrocarbons, which were a kind of typical precursor of catalyst coking deactivation and carcinogenic pollutants.

Synthesis of Ni–Mo–N catalysts for removing oxygen from acetophenone

Ni–Mo–N precursor was synthesized via a complexation reaction using nickel acetate, ammonium molybdate and hexamethylenetetramine (HMT) as starting materials and then heat-treated at high temperature in hydrogen atmosphere to obtain the final catalyst. The effects of preparation conditions such as Ni/Mo molar ratio and treatment temperature on the catalytic hydrodeoxygenation (HDO) activity were studied by taking acetophenone as a carboxide in bio-oil. 100% Conversion with a 99.1% selectivity of ethylbenzene was achieved after reaction at 150 °C for 1 h. The deoxygenation degree was further enhanced by increasing the reaction temperature and hydrogen pressure. The high activity of Ni–Mo–N catalyst was attributed to the formation of Ni2Mo3N phase. During the reusability test, acetophenone conversion on Ni–Mo–N catalyst was almost unchanged, but the deoxygenation degree was slightly lowered with the increase of recycle number, which was mainly caused by the nitrogen loss.

STYRENE PRODUCTION BY SEQUENTIAL SYNTHESIS AND BUTADIENE-1,3 CYCLODYMERS DEHYDROGENATION

The paper presents the results of the experimental research of a two-stage process for styrene production from butadiene-1,3 by a sequential synthesis of the butadiene-1,3 (4-vinylcyclohexene-1 and cyclooctadiene) cyclodimers in the first stage and styrene – in the second stage. The purpose of the research is to increase the productivity of the process and its selectivity and to simplify the technology for producing styrene and ethylbenzene from one type of raw material – n-butane. The possibility of producing 4-vinylcyclohexene-1 and cyclooctadiene by thermal and catalytic butadiene-1,3 dimerization on batch and continuous installations using copper nitrate, copper [Cu(NH3)4] (NO2) complex salt, iron pentacarbonyl, iron trichloride as catalysts is shown, as well as the regularities of the thermal butadiene dimerization process in the gas phase are established. The goal has been achieved by carrying out the synthesis of butadiene dimers on a flow-through installation in the gas phase at a high temperature and low pressure, in the presence of water vapor and a gum inhibitor. The results of laboratory research of the process for the styrene production by 4-vinylcyclohexene-1 dehydrogenation at the industrial catalysts for the hydrocarbons dehydrogenation: palladium 1.0% Pd/γ-Al2O3 (AP), platinum 0.6% Pt/γ-Al2O3 (IP-62), iron-chromium-potassium oxide (K-28) aluminum-chromium granulated for one-step dehydrogenation of n-butane produced by "Houdry" are presented. The possibility of styrene production by 4-vinylcyclohexene-1 dehydrogenation at the industrial catalyst for the ethylbenzene dehydrogenation has been established. It is shown that turning 4-vinylcyclohexene-1 into styrene occurs with an increase in temperature above 400 °C through the ethylbenzene-forming stage. When dehydrating 4-vinylcyclohexene-1, selectivity for ethylbenzene on the aluminum-chromium catalyst for the dehydrogenation of paraffin hydrocarbons with the composition of 18–20% Cr2O3, γAl2O3 has been revealed. According to the results obtained, optimal conditions for the process have been chosen.