Surface Modification of Nanocrystalline Zeolite X and Its Application as Catalyst in Synthesis of Cumene in a Packed Bed Flow Reactor: A Kinetic Study

AbstractIn the present investigation, synthesis of cumene by transalkylation of 1, 4 DIPB with benzene was studied over cerium modified nano crystalline zeolite X in a fixed bed plug flow reactor. Nano crystalline zeolite X was synthesized and characterized by XRD, SEM, TPD, EDS and FTIR. A series of nanocrystalline zeolite X (MX4, MX6, MX10) modified with ceric ammonium nitrate of different concentrations (4 %, 6 %, 10 %) was used for synthesis of cumene. MX10zeolite was proved to be the most active catalyst over which 27.12 % yield of cumene was obtained at temperature 553K, benzene/1, 4 DIPB mole ratio of 7.5 and space time-10.54 kg h/kmol. Reduction of crystal size (100–500 nm) in MX10increases surface area (633m2/gm) and thereby increases cumene yield. A kinetic rate equation was developed from the product distribution pattern following Langmuir–Hinshelwood approach. Kinetic parameters were estimated by nonlinear regression analysis. The activation energy for transalkylation and isomerisation reaction was found to be 88.86 kJ/mol and 99.04 kJ/mol respectively.

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Comparison of Raschig Ring Packing Pattern via Mean Resident Time using CFD Particle Tracing Technique: Dry Methane Reforming for Case Study

10.20944/preprints201810.0077.v1 ◽

2018 ◽

Author(s):

Nattaporn Chutichairattanaphum ◽

Phavanee Narataruksa ◽

Karn Pana-Suppamassadu ◽

Sabaithip Tungkamani ◽

Chaiwat Prapainainar ◽

...

Keyword(s):

Flow Reactor ◽

Flow Behavior ◽

Plug Flow ◽

Tubular Reactor ◽

Packed Bed ◽

Methane Reforming ◽

Particle Tracing ◽

Raschig Ring ◽

Resident Time

This paper aims to study the effect of raschig ring packing patterns using Computational Fluid Dynamics (CFD). CFD module of particle tracing was established to measure particles diffusing through the packed bed. The support raschigs catalyst was modeled in three patterns within a tubular reactor – namely, vertical staggered, chessboard staggered and reciprocal staggered pattern. A case study of Dry Methane Reforming (DMR) was investigated at 600°C, 1 atm. The study of Mean Resident Time (MRT) and E(t) function were investigated to identify the packing pattern performance. The results showed that the minimum value of the E(t), which means the flow behavior, was close to ideal plug flow behavior. MRT can be used to systematically identify the deviation from the ideal plug flow reactor of the three different packing patterns.

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Surface Modification of Nanocrystalline Zeolite X and Its Application as Catalyst in Synthesis of Cumene in a Packed Bed Flow Reactor: A Kinetic Study

nano Online ◽

10.1515/nano.0019.00021 ◽

2018 ◽

Author(s):

Ruchika Thakur ◽

Sanghamitra Barman ◽

Gopinath Halder

Keyword(s):

Surface Modification ◽

Kinetic Study ◽

Flow Reactor ◽

Packed Bed ◽

Zeolite X

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From batch to continuous: Au-catalysed oxidation of d-galacturonic acid in a packed bed plug flow reactor under alkaline conditions

Reaction Chemistry & Engineering ◽

10.1039/c8re00047f ◽

2018 ◽

Vol 3 (4) ◽

pp. 540-549 ◽

Cited By ~ 2

Author(s):

F. van der Klis ◽

L. Gootjes ◽

J. van Haveren ◽

D. S. van Es ◽

J. H. Bitter

Keyword(s):

Galacturonic Acid ◽

Flow Reactor ◽

Plug Flow ◽

Packed Bed ◽

Plug Flow Reactor ◽

Catalysed Oxidation ◽

Alkaline Conditions

Comparing the Au-catalysed oxidation of sugar acids: highest selectivity obtained in batch, superior productivity in flow.

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Synthesis of Ethyl Phenol over Modified HZSM-5 Catalyst in a Fixed Bed Reactor

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2018-0224 ◽

2019 ◽

Vol 17 (7) ◽

Cited By ~ 1

Author(s):

Renuka Saharan ◽

Gopinath Halder ◽

Sanghamitra Barman

Keyword(s):

Flow Reactor ◽

Linear Regression Analysis ◽

Nitrate Solution ◽

Fixed Bed ◽

Fixed Bed Reactor ◽

Ceric Ammonium Nitrate ◽

Optimum Operating ◽

Optimum Operating Condition ◽

Modified Zeolite ◽

Ammonium Nitrate Solution

Abstract The selective synthesis of p-ethyl phenol in vapor phase alkylation of phenol with ethanol was investigated in a fixed bed flow reactor on cerium modified zeolite CeZSM5 at temperature 693 K. A series of cerium modified zeolite such as Ce4ZSM54, Ce6ZSM56, Ce8ZSM58, Ce10ZSM5 were prepared by modifying with 4 %, 6 %, 8 % and 10 % ceric ammonium nitrate solution respectively. HZSM-5 zeolite exchanged with 10 % cerium nitrate solution was proved to be the best of all the catalyst used. The modified catalyst was further characterized by SEM, XRD and EDS. Phenol reacted with ethanol to form ethylphenyl ether by O-alkylation, and p-ethylphenol- and o-ethylphenol isomers by C-alkylation; secondary products were m-ethylphenol and dialkylated compounds. Reactions were carried out in the temperature 623 K–693 K, reactant mole ratio 0.2–0.5 over modified HZSM-5 zeolite. The optimum operating condition for maximum selectivity of p-ethyl phenol were EtOH to phenol mole ratio, 4:1; temperature, 623 K; space-time, 10.2 kg h/kmol and 1 atm pressure. A detailed kinetic study was carried out for the ethyl phenol synthesis reaction. From the product distribution pattern, a kinetic model for the reactions was proposed following the Langmuir–Hinshelwood approach. The kinetic and adsorption parameters of the rate equation were determined by non-linear regression analysis. From the kinetic analysis of the experimental data, the apparent activation energy for the reaction was determined as 43.27 kJ/mol.

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Design Cum Performance Equation for a Reactor Type Adsorption Unit

Journal of Scientific Research ◽

10.3329/jsr.v1i3.2592 ◽

2009 ◽

Vol 1 (3) ◽

pp. 450-460

Author(s):

M. A. Islam ◽

M. S. I. Mozumder ◽

M. M. R. Khan

Keyword(s):

Conventional Method ◽

Flow Reactor ◽

Plug Flow ◽

Fixed Bed ◽

Optimal Operation ◽

Operating Conditions ◽

Adsorption System ◽

Column Test ◽

Physico Chemical ◽

Reactor Type

The conventional method for designing a fixed bed adsorption unit has been discussed. The method is based on the data obtained from an adsorption column test. The characterization of an adsorption system, however, is performed in a laboratory batch experiment. It is shown that the conventional method does not make proper use of the physico-chemical parameters of an adsorption system determined by batch test. Also the method fails to predict the performance of an adsorption unit, if the operating condition differs from that under which the column test has been conducted for design purposes. New design equation has been proposed for both ‘Constantly Stirred Tank Reactor (CSTR)’ and ‘Plug Flow Reactor (PFR)’ type adsorption units. The equation predicts the performance of a reactor type adsorption unit under varying operating conditions. The proposed method is based only on the data obtained in batch experiment.Keywords: Adsorption; Unit design; Reactor; Optimal Operation, Dosage; Coefficient of utilization.© 2009 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.DOI: 10.3329/jsr.v1i3.2592 J. Sci. Res. 1 (3), 450-460 (2009)

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Catalyst Stability Assessment in a Lab-Scale Liquid-Solid (LS)² Plug-Flow Reactor

Catalysts ◽

10.3390/catal9090755 ◽

2019 ◽

Vol 9 (9) ◽

pp. 755 ◽

Cited By ~ 3

Author(s):

Anton De Vylder ◽

Jeroen Lauwaert ◽

Stijn Van Auwenis ◽

Jeriffa De Clercq ◽

Joris W. Thybaut

Keyword(s):

Catalyst Deactivation ◽

Flow Reactor ◽

Catalyst Activity ◽

Plug Flow ◽

Experimental Tests ◽

Packed Bed ◽

Plug Flow Reactor ◽

Catalyst Stability ◽

Commercial Resin ◽

Intrinsic Kinetics

A packed-bed plug-flow reactor, denoted as the lab-scale liquid-solid (LS)² reactor, has been developed for the assessment of heterogeneous catalyst deactivation in liquid-phase reactions. The possibility to measure intrinsic kinetics was first verified with the model transesterification of ethyl acetate with methanol, catalyzed by the stable commercial resin Lewatit K2629, for which a turnover frequency (TOF) of 6.2 ± 0.4 × 10−3 s−1 was obtained. The absence of temperature and concentration gradients was verified with correlations and experimental tests. The potential for assessing the deactivation of a catalyst was demonstrated by a second intrinsic kinetics evaluation where a methylaminopropyl (MAP)-functionalized mesoporous silica catalyst was used for the aldol reaction of acetone with 4-nitrobenzaldehyde in different solvents. The cooperative MAP catalyst deactivated as a function of time on stream when using hexane as solvent. Yet, the monofunctional MAP catalyst exhibited stable activity for at least 4 h on stream, which resulted in a TOF of 1.2 ± 0.1 × 10−3 s−1. It did, however, deactivate with dry acetone or DMSO as solvent due to the formation of site-blocking species. This deactivation was mitigated by co-feeding 2 wt % of water to DMSO, resulting in stable catalyst activity.

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Nanostructured catalysts for BIOEthanol transformation to industrially important chemicals

Acta Chimica Slovaca ◽

10.2478/acs-2021-0009 ◽

2021 ◽

Vol 14 (1) ◽

pp. 66-78

Author(s):

Blažej Horváth ◽

Matúš Petrík ◽

Dana Gašparovičová ◽

Tomáš Soták

Keyword(s):

Flow Reactor ◽

Low Cost ◽

Plug Flow ◽

Value Added ◽

Nanostructured Catalysts ◽

Product Distribution ◽

Catalytic Transformation ◽

Basic Catalysts ◽

Acid Catalyzed ◽

The Impact

Abstract Utilization of a low-cost biomaterial, such as bioethanol, to produce value–added compounds for current industry has been investigated. This work is focused on the catalytic transformation of bioethanol into industrially significant alkenes. Catalytic transformation of ethanol was studied using catalysts based mainly on nanostructured materials as Mg-Al hydrotalcites, sepiolites and zeolites doped with Cu, K, Sr, Zn and Mn. The catalytic tests were carried out in a plug-flow reactor in the temperature range of 350—550 °C. Undoped zeolites promote acid-catalyzed dehydration of ethanol, while in case of basic catalysts, such as hydrotalcites, the product distribution is shifted toward butadiene. The impact of the hydrotalcites preparation method on their structure and catalytic activity is reported. It was found that hydrotalcite with well-developed layered structure, prepared by slow hydrolysis, promotes the formation of butadiene (with butadiene yield of 28.2 % at 400 °C vs. ethylene yield of 17.2 % at 550 °C).

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Robust generic model feedback under model uncertainties: Application of a tubular reactor for the treatment of industrial plating wastewater

Journal of Applied Research and Technology ◽

10.22201/icat.16656423.2008.6.03.522 ◽

2008 ◽

Vol 6 (03) ◽

Author(s):

Ricardo Aguilar-López ◽

Ricardo Acevedo-Gómez ◽

María Isabel Neria González ◽

Alma Rosa Domínguez-Bocanegra

Keyword(s):

Flow Reactor ◽

Laboratory Data ◽

Plug Flow ◽

Tubular Reactor ◽

Generic Model ◽

Model Uncertainties ◽

Kinetic Rate ◽

Integral Action ◽

The Stability ◽

Plating Wastewater

The goal of this work is to describe the design of a feedback controller to regulate the Hexavalent chromium (Cr (VI)) concentration in industrial plating wastewater in a tubular reactor. Cr(VI) is a major pollutant present in industrial wastewaters common to the metal and mineral processing as well as to plating industries. For control purposes, a dynamic model of a plug flow reactor with dispersion is developed in the form of partial differential equations (PDE) via applying classical conservation principles; this model is experimentally corroborated using laboratory data. The proposed controller is based on uncertainty observer to infer unknown terms as diffusive transport and Cr(VI) kinetic rate; also Generic Model Controller (GMC) is coupled with this estimation methodology to provide robustness against model uncertainties. The controller leads to nonlinear PID plus double integral action, where the tuning rules are given in terms of the observer and GMC gains. A theoretical frame is given in order to show the stability properties of the closed-loop system under the proposed controller. Numerical simulation illustrates performance of the methodology proposed; a comparison with observer based I/O linearizing controller and a well tuned PID controller is done, which allows concluding that the observer based Generic Model Controller exhibits better performance.

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