Reaction Of Benzene Research Articles

An advanced bath model to simulate association followed by ensuing dissociation dynamics of benzene + benzene system: a comparative study of gas and condensed phase results.

The role of the environment (N2 molecules) on the association followed by the ensuing dissociation reaction of benzene + benzene system is studied here with the help of a new code setup. Chemical dynamics simulations are performed to investigate this reaction in vacuum as well as in a bath of 1000 N2 molecules, equilibrated at 300 K. Bath densities of 20 and 324 kg m-3 are considered with a few results from the latter density. The simulations are performed at three different excitation temperatures of benzene, namely, 1000, 1500, and 2000 K, with an impact parameter range of 0-12 Å for both vacuum and bath models. Higher association probabilities and hence, higher temperature dependent association rate constants are obtained in the condensed phase. In the condensed phase, when a trajectory takes a longer time for the monomers to associate, the associated complex is formed with a longer lifetime and provides a lower rate of ensuing dissociation. Higher association rate and lower dissociation rate in condensed phase dynamics are due to the energy transfer process. Hence, the energy transfer phenomenon plays a decisive role in the association/dissociation dynamics, which is completely ignored in the same reaction when studied in vacuum.

Engineering atomically dispersed single Cu–N3 catalytic sites for highly selective oxidation of benzene to phenol

A single-atom Cu catalyst with a CuN3 structure is prepared by a facile and practical strategy, the pyrolysis method, showing desirable conversion and selectivity for the oxidation reaction of benzene to phenol.

The The perceptions of Senior High School students and teachers about organic chemistry: A Ghanaian perspective

The purpose of the study was to determine the perceptions that senior high school (SHS) chemistry students and teachers have about organic chemistry as well as to compare organic chemistry topics that are difficult for students and teachers. Simple random sampling (lottery) and purposive sampling methods were used to select a sample of one hundred (100) SHS students who studied elective chemistry and ten (10) chemistry teachers. The research instruments used to collect data for this study were the ‘organic chemistry perceptions questionnaire for students’ (OCPQS) and ‘organic chemistry perceptions questionnaire for teachers’ (OCPQT). Descriptive statistics (frequencies and percentages) were used to analyze the data collected. The findings revealed that these SHS students have a fairly positive perception of organic chemistry while their teachers had a highly positive perception of organic chemistry. Preparation and chemical reactions of alkenes, preparation and chemical reactions of alkynes, structure and stability of benzene, reactions of benzene, comparison of reactions of benzene and alkenes, petroleum, polymers and naming of alkanes and structural isomerism were perceived by students as difficult to understand. The rest of the Ghanaian SHS organic chemistry topics (26 out of 34 topics) were perceived as easy to understand by students. Also, the teachers perceived all the SHS organic chemistry topics as easy to teach with the exception of reactions of benzene. The insights gained about teachers’ and students’ perceived difficult organic chemistry topics in this study imply that teachers’ perceptions and how these are communicated to students can have significant effects on learning. The authors believe that both teachers and learners could benefit from this increased awareness of perceptions about difficulties in teaching and learning organic chemistry. They therefore suggest that further studies into how teachers’ perceptions influence their teaching and consequently their students’ experiences be carried out. In addition, in future research, a diagnostic test based on the topics in the SHS organic chemistry syllabus could be added to ascertain whether the perceived difficult topics are actually difficult for students to answer questions on. This would help teachers to separate perceived difficulties from the actual difficulties (realities) and be able to address them in their lessons.

Optimizing bromide anchors for easy tethering of amines, nitriles and thiols in porous organic polymers towards enhanced CO2 capture

Porous organic polymers with labile leaving groups offer direct access to reactive functional groups, otherwise not permissible during network formation. In a one-step, open air, self-coupling reaction of tris bromomethyl benzene, we report highly porous, bromine rich C–C bonded porous polymers. Due to the steric nature of the monomer, restrictive crosslinking allowed pendent bromine groups to remain unreacted and provided rapid exchange into amines, nitriles, and thiols. This simple but powerful strategy yielded two isostructural but varying porosity and pendent group density polymers, allowing a comparative gas uptake study. Despite having lower surface area, the porous polymer formed at low temperature showed higher amination due to higher density of bromine groups. The polymers with more pendant groups resulted better CO 2 uptake performances than higher porosity polymers with less pendant groups. Although post-modification decreased surface area of materials, amine functionalization greatly improved the CO 2 uptake capacity. The ethylenediamine appended version exhibited 4.7 times increase in CO 2 uptake capacity with highest CO 2 /N 2 selectivity of 729 (298 K), and with an isosteric heat of 97 kJ mol −1 at zero coverage. • The one-step synthesis of bromine tethered C–C bonded nanoporous polymers. • The tuning of porosity and number of bromine anchors by changing reaction temperature. • Successful tailoring of benzyl bromides with amine, thiol, and nitrile moieties. • The density of surface functional groups exhibits higher impact on CO 2 adsorption performance than porosity.

Novel Vanadia/meso-Co3O4 catalysts for the conversion of benzene–toluene–xylene to environmental friendly components via catalytic oxidation

ABSTRACT Three – dimensional meso-porous Co3O4 was prepared by nanocasting pathway based on the use of mesoporous silica (KIT-6) as hard template with different Cobalt concentrations (0.5–2.5 mol ratio based on mesoporous silica KIT-6). The prepared samples was used as supports for preparing V2O5/Co3O4 (1, 6 wt% of V2O5) catalysts. The prepared samples were characterized by different techniques. The catalytic activity of the prepared samples were evaluated in the complete oxidation reaction of toluene, benzene, and/or p-xylene; (as model reactants of volatile organic compounds) in terms of CO2. The catalytic reaction was carried out in a fixed-bed micro-reactor operated under atmospheric pressure and within the reaction temperature range of 200–400 °C. The data confirmed that the three dimensional-mesoporous Co3O4 (1.0 mole ratio) replicated sample possessed improved different parameters compared to those of the Co3O4 sample with other mole ratios. The data reflected the yield of Co2 is decreased upon the increase in reaction temperature to 400°C. 1 wt.% V2O5/m-Co3O4 catalyst shows a reverse direction, the CO2 yield slowly increased in the range 150–250 °C, then jumped at 300 °C until maximum yield (100%) is observed at 400 °C. 1 wt.% V2O5/m-Co3O4 catalyst was found to be the active and selective promised catalyst for the complete oxidation of either individual aromatic volatile organic compounds (benzene, toluene, and/or xylene) and/or their mixtures to 100% CO2.

One-pass conversion of benzene and syngas to alkylbenzenes by ZnAlOx/ZSM-5 composite catalyst

Alkylbenzenes are important bulky chemicals. The production of alkylbenzenes through benzene and syngas alkylation technology of coal chemical industry can reduce the domestic dependence on petroleum. In this study, mechanical mixture of ZnAlO>x and ZSM-5 were used to catalyze the alkylation reaction of benzene and syngas. The results showed that the best performance catalyst was obtained with the 1:1 mass ratio of the two components and the 2:1 molar ratio of zinc to aluminum. It was suggested that the main reaction intermediates of methanol and dimethyl are produced on the O vacancy of ZnO and L acidic center of Al2O3 in ZnAlOx. And the alkylated benzenes are formed by the reaction of benzene with the intermediates over ZSM-5. Due to the high temperature property of ZnAlOx for methanol synthesis which can accommodate to the reaction of ZSM-5 for benzene alkylation, the high catalytic activity and selectivity was obtained.

Crossed-Beam and Theoretical Studies of the O(3P, 1D) + Benzene Reactions: Primary Products, Branching Fractions, and Role of Intersystem Crossing.

Reliable modeling of hydrocarbon oxidation relies critically on knowledge of the branching fractions (BFs) as a function of temperature (T) and pressure (p) for the products of the reaction of the hydrocarbon with atomic oxygen in its ground state, O(3P). During the past decade, we have performed in-depth investigations of the reactions of O(3P) with a variety of small unsaturated hydrocarbons using the crossed molecular beam (CMB) technique with universal mass spectrometric (MS) detection and time-of-flight (TOF) analysis, combined with synergistic theoretical calculations of the relevant potential energy surfaces (PESs) and statistical computations of product BFs, including intersystem crossing (ISC). This has allowed us to determine the primary products, their BFs, and extent of ISC to ultimately provide theoretical channel-specific rate constants as a function of T and p. In this work, we have extended this approach to the oxidation of one of the most important species involved in the combustion of aromatics: the benzene (C6H6) molecule. Despite extensive experimental and theoretical studies on the kinetics and dynamics of the O(3P) + C6H6 reaction, the relative importance of the C6H5O (phenoxy) + H open-shell products and of the spin-forbidden C5H6 (cyclopentadiene) + CO and phenol adduct closed-shell products are still open issues, which have hampered the development of reliable benzene combustion models. With the CMB technique, we have investigated the reaction dynamics of O(3P) + benzene at a collision energy (Ec) of 8.2 kcal/mol, focusing on the occurrence of the phenoxy + H and spin-forbidden C5H6 + CO and phenol channels in order to shed further light on the dynamics of this complex and important reaction, including the role of ISC. Concurrently, we have also investigated the reaction dynamics of O(1D) + benzene at the same Ec. Synergistic high-level electronic structure calculations of the underlying triplet/singlet PESs, including nonadiabatic couplings, have been performed to complement and assist the interpretation of the experimental results. Statistical (RRKM)/master equation (ME) computations of the product distribution and BFs on these PESs, with inclusion of ISC, have been performed and compared to experiment. In light of the reasonable agreement between the CMB experiment, literature kinetic experimental results, and theoretical predictions for the O(3P) + benzene reaction, the so-validated computational methodology has been used to predict (i) the BF between the C6H5O + H and C5H6 + CO channels as a function of collision energy and temperature (at 0.1 and 1 bar), showing that their increase progressively favors radical (phenoxy + H)-forming over molecule (C5H6 + CO and phenol stabilization)-forming channels, and (ii) channel-specific rate constants as a function of T and p, which are expected to be useful for improved combustion models.

Co-Crystalline ZSM-5/ZSM-11 Nanostructures for Alkylation of Benzene with Ethanol

The interzeolite transformation approach has been used extensively for the quick synthesis of zeolites at a lower cost. Herein, an interzeolite transformation method for the quick synthesis of co-crystalline ZSM-5/ZSM-11 (CDM-5) nanoaggregates has been developed by precisely controlling the synthesis parameters and using 1,6-hexamethylenediamine as an organic structure-directing agent. In contrast, the irregular CDM-5 zeolite block obtained from an amorphous aluminosilicate gel takes a longer crystallization time using the conventional method. Combined with the related results of characterization, UV-Raman spectra show that double 6-membered rings in the parent USY zeolite framework are broken, and an ordered aluminosilicate aggregate species (OAAS) containing 4-membered rings (4Rs) are formed during the interzeolite transformation. HRTEM and SEM images demonstrate that the block OAAS is dissolved into amorphous nanoparticles, followed by converting into CDM-5 nanoaggregates. These results reveal that an OAAS is essential for the synthesis of CDM-5 nanoaggregates via the interzeolite transformation method. In addition, the CDM-5 nanoaggregate catalyst exhibits superior stability and resistance to carbon deposition in the alkylation reaction of benzene with ethanol compared with the irregular block CDM-5 catalyst.

Study on using cellulose derivatives as pore directing agent for preparation of hierarchical ZSM-5 zeolite catalyst

Cellulose derivatives such as hydroxyethylmethylcellulose (HEMC), and hydroxypropylmethylcellulose (HPMC), which are originated from biomass, were used as mesoporous directing agent for the synthesis of hierarchical ZSM-5 zeolite. Hierarchical ZSM-5 zeolites with outstanding mesoporosity and high hierarchy factors were achieved by hydrothermal method in the presence of bio-mesoporogen. The as-synthesized hierarchical ZSM-5 zeolites were characterized by X-ray diffraction (XRD), nitrogen adsorption–desorption (BET), scanning electron microscope (SEM) to determine the structure of samples. The influences of different mesoporogens with different dosage in the synthetic process on the physicochemical and catalytic properties of hierarchical ZSM-5 zeolite were investigated. Possession of the high mesopores, high surface areas and abundant accessible acid sites, the hierarchical zeolites exhibited excellent catalytic performance in the alkylation reaction of benzene and benzyl alcohol.

Carbon clusters formed from shocked benzene

Benzene (C6H6), while stable under ambient conditions, can become chemically reactive at high pressures and temperatures, such as under shock loading conditions. Here, we report in situ x-ray diffraction and small angle x-ray scattering measurements of liquid benzene shocked to 55 GPa, capturing the morphology and crystalline structure of the shock-driven reaction products at nanosecond timescales. The shock-driven chemical reactions in benzene observed using coherent XFEL x-rays were a complex mixture of products composed of carbon and hydrocarbon allotropes. In contrast to the conventional description of diamond, methane and hydrogen formation, our present results indicate that benzene’s shock-driven reaction products consist of layered sheet-like hydrocarbon structures and nanosized carbon clusters with mixed sp2-sp3 hybridized bonding. Implications of these findings range from guiding shock synthesis of novel compounds to the fundamentals of carbon transport in planetary physics.

Determination of the Rate Constant of the Reaction of Benzene with Atomic Fluorine by the Method of Competing Reactions

Determination of the Rate Constant of the Reaction of Benzene with Atomic Fluorine by the Method of Competing Reactions

Combined dealkylation and transalkylation reaction in FCC condition for efficient conversion of light fraction light cycle oil into value-added products

The light fraction light cycle oil (LLCO) rich in alkyl-benzene and alkyl-naphthalene with short chains is expected to have a dealkylation reaction to produce value-added products. However, since the high bond energy of its side chains, low reactivity is inevitable under catalytic cracking circumstance. In this work, the catalytic cracking performance of 1,2,4,5-TeMBs, as a model molecule of LLCO, was evaluated in FCC condition. Interestingly, the benzene additive can contribute to the conversion of 1,2,4,5-TeMBs by transalkylation reaction. Based on this, we investigated the effect of benzene on the catalytic cracking of LLCO. Compared with the catalytic cracking of LLCO alone, higher reactivity of macromolecular alkyl-benzene and alkyl-naphthalene was achieved when benzene was used as an additive in LLCO. Meanwhile, a high yield of toluene was observed produced from the transalkylation reaction of benzene. Furthermore, several zeolite catalysts were evaluated for efficient conversion of a mixture of benzene and LLCO. The results indicated that the mesoporous BEA zeolite with the appropriate acidity property and mass transfer ability was regarded as the optimal catalyst given its highest yield of value-added products.

Exploration of the Influences of the PODE3 Additive on the Initial Pyrolysis of Diesel by ReaxFF Molecular Dynamics Simulations

Understanding the pyrolysis mechanism of oxygenated additives blending with diesel fuel is of great importance for the in-depth research of diesel additives and soot formation. In this work, molecular dynamics simulations combined with reactive force field (ReaxFF) were performed to study the initial pyrolysis mechanisms of PODE3 and its effects on the pyrolysis of different types of diesel compounds including hexadecane, cyclopentane, benzene, and naphthalene as an additive. The simulations at 2400 K showed that the initial pyrolysis of PODE3 starts with the dissociation of C–O bonds and proceeds in four directions. The bond dissociation energies of C–O bonds have an impact on the initial reaction selectivity, and subsequently, products are continuously pyrolyzed to form a pyrolysis reaction network, the end of which are CH2O, CH3O·, ·CH3, and H·. The results further revealed that the intermolecular reactions make reactions and product types more complex. The calculated activation energy of PODE3 under 2100 to 2700 K is 45.5 kcal/mol with a pre-exponential factor of 1.14 × 1015. For binary blending systems of diesel compounds and PODE3, it was found that the rapid pyrolysis of PODE3 creates a radical-rich environment in the initial stage of the simulation, which promotes the pyrolysis of hexadecane and the ring-opening reactions of cyclopentane, benzene, and naphthalene. After the ring-opening reactions, cyclopentane and benzene molecules continue to be pyrolyzed into small species, while naphthalene will form monocyclic aromatic hydrocarbons.

Realization of rapid synthesis of H-ZSM-5 zeolite by seed-assisted method for aromatization reactions of methanol or methane

H-ZSM-5 zeolites are successfully synthesized within 1 h with an organic template free system by the seed-assisted method. The synthetic method not only reduces the production cost of H-ZSM-5 zeolite, but also decreases the environmental pollution produced compared with that of the conventional synthesis process. Characterization by SEM, XRD, N2 adsorption–desorption, NH3-TPD, and Py-IR confirms that the H-ZSM-5 product has a high crystallinity and reveals that the rapid synthesis process is in accordance with the seed surface crystallization mechanism. To improve the aromatic selectivity on the H-ZSM-5 zeolite, different concentrations of Mo and Zn catalysts were prepared by incipient wetness impregnation and the ion-exchange method. Mo-Zn/H-ZSM-5-SAS-1 h have similar catalytic lifetimes and higher selectivity of paraxylene in aromatic products compared with Mo-Zn/H-ZSM-5-seed in the reaction of methanol to aromatic. However, the catalytic lifetime of 6%Mo/H-ZSM-5-SAS-1 h is shorter than that of the 6%Mo/H-ZSM-5-seed catalyst in methane to benzene reaction under the same reaction conditions.

Au@SnO2 and SnO2@Au Hollow Spheres for Gas Sensor Applications: Selectivity Control

Introduction Metal oxide semiconductor (MOS) based gas sensors have attracted growing attention due to their excellent gas sensing characteristics, reasonable price, and facile integration. However, MOS based gas sensors show similar gas responses to a number of gases, which means that selective detection to the gases remains challenging. It has been frequently reported that the selectivity of MOS gas sensors can be controlled by doping or loading noble metal catalysts. In this research, we suggest that not only the type but also the location of catalysts in the nanostructure may cause a change in gas selectivity. We fabricated Au@SnO2 and SnO2@Au sensors and measured their sensing characteristics. : SnO2 hollow nanospheres whose inner part or outer part of shell are decorated with 0.3 at% Au. Method 0.15 g of sulfonated polysrtrene (SPS) beads were dispersed in 30 mL ethanol, and 0.075 g of poly-vinylpyrrolidone (PVP, MW = 40,000) was dissolved in 30 mL distilled water. Two solutions were mixed and homogenized by magnetic stirring. 30 mL of SnSO4, (95%) aqueous solution (0.07 M) were added drop by drop to the mixed solution. The solution was stirred at room temperature for 12 h, and subsequently washed and centrifuged five times with distilled water and ethanol. Finally, the precursor powders (SPS@Sn) were converted into SnO2 hollow spheres via a heat treatment at 550 °C for 2 h in air (2 °C min-1).0.0021 g of HAuCl4∙3H2O (99.999%) was dissolved in 30 mL ethanol containing 0.15 g of SPS. After magnetic stirring at room temperature for 2 h, 10 mL of NaBH4 (99.99%) aqueous solution (0.0026 M) was injected drop by drop into Au contained SPS suspension and stirred at 60 °C for 2 h. After washing and centrifuging five times with distilled water and ethanol, the suspensions were dried at 70 °C for 6 h to obtain SPS@Au. To confine the Au nanoparticles inside SnO2 hollow shell, SPS@Au were coated with Sn precursor in the same way as the synthesis of SPS@Sn.To load the Au nanoparticles outside the SnO2 hollow shell, Au was loaded on the as-prepared SPS@Sn, followed by SPS@Sn@Au. Loading Au on the surface of SnO2 was followed the previous way of preparing SPS@Au. The ratio between Au, and Sn ([Au] / [Sn]) were fixed to 0.3 at%. Results and Conclusions The pure SnO2 sensor exhibited the highest response to ethanol and the responses to other analyte gases (HCHO, p-xylene, toluene, benzene, and CO) were low at all sensing temperatures (300 – 375 oC). Both Au-out-SnO2 and Au-in-SnO2 showed significantly enhanced responses to all the analyte gases. However, they showed completely different gas selectivity depending on the location of Au catalysts. The Au-out-SnO2 sensor showed the highest gas response to 5 ppm ethanol over the entire range of sensing temperatures and this sensing characteristics are similar to those of pure SnO2 sensor although the maximum gas response levels were different from each other. In contrast, the Au-in-SnO2 sensor showed the highest response to p-xylene at 300 - 350 oC. Moreover, the responses to toluene and benzene were higher than those of ethanol at 350 and 375 oC. High response to xylene and relatively high responses to less reactive benzene and toluene can be attributed to the reforming of aromatic compounds into more reactive species for gas sensing. The catalyst-loaded micro reactor is a good model system to understand the gas sensing mechanism and provide a promising platform to detect the aromatic indoor pollutants in a highly sensitive and selective manner.

Updated yields of nitrogenated species in flames of ammonia/benzene via introducing an aniline sub-mechanism

Ammonia and cyclic aromatic compounds are principal products from combustion of various fractions of biomass. Yet, kinetic mechanistic models on formation of NOx from biomass de-couple the oxidation mechanism of ammonia from that of aromatic molecules. Literature kinetic models do not consider a plausible formation of aniline as the initial product from the interaction of amine radicals and benzene molecules (as the simplest aromatic molecule). Such reaction acts a sink for NH2 radicals, and thus may alter the yields of NOx and HCN. To fill in this gap, this study reports production pathways of aniline from NH2 + benzene reactions, maps out unimolecular decomposition pathways of aniline and its derived anilino radical into, and explores the effect of the title reaction on the yields of small nitrogenated species from co-combustion of ammonia and benzene. We find that anilino radical to preferentially decompose into iso-HNC and a cyclopentadienyl radical. The resonance-stabilized structure of the anilino radical enables it to undergo bimolecular reaction with the aniline molecule to generate N-analogous compounds of dioxins, namely diphenylamine, carbazole, and phenazine. Detail kinetic modeling discloses that decomposition of aniline initiates at 1100 K with ammonia and HCN signify the most abundant N-bearing species at intermediates and high temperatures, respectively. Introducing the newly constructed aniline sub-mechanism in NOx + benzene kinetic model from the literature (i.e., CERCK model) alters predicted concentrations of principal N species within factors of 1.2- 2 between 1100–1300 K. It is hoped that reaction rate constants and mechanistic pathways presented herein to improve the predictive performance of kinetic models that address NOx and HCN emission from flames of ammonia and aromatic-containing fuels in general.

The inhibition of mild steel corrosion in 0.5 M H2SO4 solution by N-phenethylhydrazinecarbothioamide (N-PHC)

A new corrosion inhibitor namely N-phenethylhydrazinecarbothioamide (N-PHC) was synthesized through the reaction of hydrazine hydrate and (2-isothiocyanatoethyl)benzene. N-PHC has been characterized by spectroscopically techniques and CHN micro-elemental analysis. The inhibitive activity of N-PHC on mild steel corrosion in 0.5 M sulphuric acid solution was examined by the weight loss techniques. The findings exhibited that the inhibition efficiency increased with an increase in the concentration of N-PHC and decreased with an increase in temperature. The inhibition efficiency reached 94.7% with 250 ppm at 303 K. The inhibitive mechanism involved chemical adsorption and the adsorption of the N-PHC molecules through active sites on the surface of mild steel to control or retard corrosion. The adsorption isotherm obeyed the Langmuir isotherm.

Chemical effect on muonic atom formation through muon transfer reaction in benzene and cyclohexane samples

Abstract To investigate the chemical effect on the muon capture process through a muon transfer reaction from a muonic hydrogen atom, the formation rate of muonic carbon atoms is measured for benzene and cyclohexane molecules in liquid samples. The muon transfer rate to carbon atoms of the benzene molecule is higher than that to the carbon atoms of the cyclohexane molecule. Such a deviation has never been observed among those molecules for gas samples. This may be because the transfers occur from the excited states of muonic hydrogen atoms in the liquid system, whereas in the gas system, all the transfers occur from the 1s (ground) state of muon hydrogen atoms. The muonic hydrogen atoms in the excited states have a larger radius than those in the 1s state and are therefore considered to be affected by the steric hindrance of the molecular structure. This indicates that the excited states of muonic hydrogen atoms contribute significantly to the chemical effects on the muon transfer reaction.

“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.

Dehydrogenative Coupling of Alkanes and Benzene Enhanced by Slurry-Phase Interparticle Hydrogen Transfer.

The dehydrogenative coupling reaction of alkanes and benzene has attracted attention as a method of direct conversion of alkanes to raw materials for useful chemical products. Here, we report the first combined catalyst system composed of hydrotalcite-supported palladium and solid acid aluminum-exchanged montmorillonite for the direct alkylation of benzene promoted by slurry-phase interparticle hydrogen transfer at 150 °C. The combination of the two catalytic particles showed excellent activity and achieved the maximum benzene conversion of 21% and target product selectivity of 84% in the reaction of n-heptane and benzene. Our results, thus, provide a feasible strategy to design efficient liquid-phase reaction systems employing simple physical mixing of two catalytic particles.