Rhenium Effect on the Performance of CoMoNi/γ‐Al2O3 Catalyst in Thiophene Hydrodesulphurization. Performance Evaluation and Process Kinetics

ChemistrySelect

Published On 2021/4/28

The rhenium effect on the performance of CoMoNi/γ‐Al2O3 catalyst was studied in thiophene hydrodesulphurization. The unsulfided and freshly sulfided catalysts were characterized by N2 adsorption‐desorption, IR spectroscopy, X‐ray photoelectron spectroscopy (XPS) and total acidity. The effects of reaction temperature, pressure, and liquid hourly space velocity (LHSV) on thiophene HDS performance shown that the activity of the CoMoNiRe/γ‐Al2O3 catalyst for thiophene HDS was superior to that of the CoMoNi/γ‐Al2O catalyst, which was mainly ascribed to the higher acidic functional groups. Based on Langmuir‐Hinshelwood approach, a kinetic model for thiophene HDS over both catalysts have been developed. In this respect, two mechanisms have been considered, one hypothesizing that hydrogen is adsorbed on different active centers than thiophene (two‐centers mechanism) and the other considering …

Journal

ChemistrySelect

Published On

2021/4/28

Volume

6

Issue

16

Page

3858-3868

Authors

Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

Position

H-Index(all)

10

H-Index(since 2020)

9

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Chemical Reaction Engineering

Ion Bolocan

Ion Bolocan

Universitatea Petrol-Gaze din Ploiesti

Position

Professor of Organic Chemistry

H-Index(all)

8

H-Index(since 2020)

6

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Chemical Engineering

Chemistry

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

Chemical Engineering Research and Design

One-stage ethanol to butadiene process: Analysis and design of a multi-tubular fixed bed reactor

The paper develops a design feasibility study of a multi-tubular polytropic fixed bed reactor for the one-stage ethanol to 1,3-butadiene (ETB) process employing a modified MgO-SiO2 catalyst. The analysis quantifies the effect of the internal diffusion on scaling up the catalyst activity and selectivity by considering a complex chemistry of seven parallel/series reactions described by detailed kinetic modelling. The efficient numerical solution takes advantage from the MATLAB™ function bvp5c. The simulation model allows scanning the catalytic process by profiles of species’ concentrations, reaction rates and effectiveness factors, inside the catalyst particle and over the reactor. The butadiene yield is controlled by the accumulation in particle of ethanol and key intermediates, as acetaldehyde and crotonaldehyde, related to internal chemical reaction with diffusion and external mass and heat transport rates. The catalyst …

Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

Catalysts

An Analysis of Fixed-Bed Catalytic Reactors Performances for One-Stage Butadiene Synthesis from Ethanol

The present study assesses, using a theoretical approach, the performances of two widely used fixed-bed reactors for the ethanol-to-butadiene (ETB) one-stage (Lebedev) process: multibed adiabatic reactors (MBAR) with inter-bed heating and a multitubular reactor (MTR). The mathematical model consists of mass and heat conservation equations at catalyst particle and particle bed scales, coupled with a published kinetic model specific for a modified MgO–SiO2 catalyst. The process simulations at the level of catalyst particle have shown that the inter-phase concentration and temperature gradients are negligible, the only physical step with a limiting influence on process kinetics being the internal diffusion. A simplified version of the reactor model was also formulated, including empirical expressions developed in the study for the calculation of internal effectiveness factors. The reactor simulations highlighted that the MBAR with inter-bed heating by injection of hot reactants provides worse butadiene (BD) yields as a consequence of reduced reaction times (due to reactant by-pass of catalyst beds). The MBAR with inter-bed heating using heat exchangers provides better performances but inferior to those of MTR if the number of catalyst beds is less than six. A preliminary optimization study for the MBAR and MTR is also presented. The results showed that the maximization of BD yield has the drawback of a low BD production rate, whereas the maximization of BD production rate corresponds to a relatively low BD yield and high ethanol and inert recycles. A trade-off between the two extreme cases can be attained by maximizing the income …

Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

Catalysts

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

Sustainability

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

Coprecipitation nanoarchitectonics for the synthesis of magnetite: A review of mechanism and characterization

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

Renewable Energy

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

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Ion Bolocan

Ion Bolocan

Universitatea Petrol-Gaze din Ploiesti

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

Scientific Reports

Mutual inhibition effect of sulfur compounds in the hydrodesulfurization of thiophene, 2-ethylthiophene and benzothiophene ternary mixture

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

Industrial & Engineering Chemistry Research

Ethanol conversion to butadiene: a thermodynamic analysis

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Ion Bolocan

Universitatea Petrol-Gaze din Ploiesti

Reaction Kinetics, Mechanisms and Catalysis

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

International Multidisciplinary Scientific GeoConference: SGEM

EFFECTS OF STRESS FACTORS IN THE GROWTH MEDIUM ON BIO-COMPOUNDS PRODUCTION BY PORPHYRIDIUM PURPUREUM

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

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Ionut BANU

Ionut BANU

Universitatea Politehnica din Bucuresti

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ChemistrySelect

Fabrication and Investigation of a MoS2/Fe3O4/PANI Composite for Supercapacitor Applications

This study investigates a successful fabrication of MoS2/Fe3O4/PANI composite by chemical co‐precipitation method. The facile hydrothermal approach was employed to synthesize a MoS2/Fe3O4 composite, followed by the utilization of a conventional chemical oxidation strategy to produce a PANI coating on the composite, thereby generating an active material for electrochemical reactions and a structure facilitating the transportation of ions via multiple pathways. The fabricated MoS2/Fe3O4/PANI composite was characterized by SEM, ICP, XRD, FT‐IR, and so on. In this study, we delved into the electrochemical charge storage feature of MoS2/Fe3O4/PANI. The electrochemical characteristics of the nanocomposite were assessed through the implementation of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronopotentiometry techniques in a 3 M KOH electrolytic solution, utilizing …

Yılmaz Uğur

Yılmaz Uğur

Inönü Üniversitesi

ChemistrySelect

Changes in the Phenolic, Melatonin, Sugar Contents and Antioxidant Capacity, Depending on Ripening Stage in Different Cornelian Cherry (Cornus mas L.) Fruits

Cornelian cherry (CC) is a source of bioactive compounds such as phenolics, melatonin and, vitamin C and used as traditional food and in folk medicine. In this study, we analyzed and compared the variation of some bioactive compounds and antioxidant capacity in CC fruits depending on ripening and genotype. CC fruit was sampled at different ripening times (unripe, semi‐ripe and ripe) and the contents of sugars, vitamin C, melatonin and phenolic compounds were analysed by ultra‐fast liquid chromatography (UFLC‐PDA). The results showed that the fruits at the unripe samples had a significantly higher chemical components and antioxidant capacity. Chlorogenic acid, catechin, gallic acid and rutin were the four major phenolic compounds identified in all genotypes. Melatonin concentration of unripe fruits was found to be high in all genotypes (ranged from 1664.78–114.60 ng/mL) and a decrease was …

Nandang Mufti

Nandang Mufti

Universitas Negeri Malang

ChemistrySelect

A Facile Route Preparation of Fe3O4/MWCNT/ZnO/PANI Nanocomposite and its Characterization for Enhanced Microwave Absorption Properties

With increasing concerns regarding the potential health risks associated with microwave‐based technology, researchers have been actively investigating materials with impressive microwave absorption properties. In this study, a synthesis and investigation of a nanocomposite, named Fe3O4/MWCNT/ZnO/PANI, consisting of magnetite (Fe3O4), multi‐walled carbon nanotube (MWCNT), zinc oxide (ZnO), and polyaniline (PANI) as a microwave‐absorbing material, was carried out for the first time. The nanocomposite was prepared through a simple physical mixing approach and demonstrated tunable microwave absorption, making it highly suitable for shielding applications. Structural analysis techniques, including X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FTIR), and scanning electron microscopy with energy‐dispersive X‐ray analysis (SEM‐EDAX), confirmed the presence of all components …

Hakan Kızıltaş

Hakan Kızıltaş

Atatürk Üniversitesi

ChemistrySelect

Synthesis of CoFe2O4/TiO2/PANI Nanocomposite Photocatalyst, and Examination of Its Decolorization Efficiency on Rhodamine B

This study aims to reduce the band gap by doping wide band‐gap TiO2 with CoFe2O4 and PANI to improve the photocatalytic efficiency and examine the decolorization kinetic of Rhodamine B (RhB). The characteristics of the nanocomposites were thoroughly assessed through the utilization of SEM‐EDS, TEM, XRD, FTIR, VSM, UV‐Vis, PL, and XPS analyses. The SEM and TEM analyses revealed that CoFe2O4/TiO2/PANI has a homogeneously porous structure. XRD analysis results were found to show good agreement with the standard diffraction data cards. The band structures obtained by FTIR analyses were compatible with literature studies. The band gap energies determined by UV‐Vis analyses were determined as 2.86 eV for CoFe2O4/TiO2/PANI. The decrease of CoFe2O4/TiO2/PANI recombination rate was proven with PL results. The different initial dye concentrations, temperature, and light intensity …

Dr. Srikrishna Saripella

Dr. Srikrishna Saripella

Banaras Hindu University

ChemistrySelect

Synthesis, Characterization, In‐Vitro and In‐Vivo Anti‐Cancer Evaluation of Novel Benzopyrylium Salts on Colorectal Cancer Model of Drosophila Melanogaster

A total of 10 benzopyrylium salts, 7 being novel, were synthesized by Claisen‐Schmidt condensation reaction and characterized by 1H and 13C NMR, High‐Resolution Mass Spectrometry, FT‐IR, and UV‐Vis spectroscopy. The purity of these synthesized compounds was determined by HPLC. The in‐vitro anti‐cancer evaluation of these synthesized benzopyrylium salts was done at National Cancer Institute (NCI), USA, against 60 human cancer cell lines. The compounds 4 and 8 showed promising anti‐cancer activities against various human cancer cell lines. The docking studies of the compounds were carried out against the oncogenic target JNK and their docking scores were compared to that of the known JNK inhibitor SP600125 (Pyrazolanthrone). Compound 4 exhibited an outstanding docking score of −9.0 kcal/mol, comparable to the docking score of SP600125 (−9.3 kcal/mol). The ex‐vivo studies in …

Faris Hermawan

Faris Hermawan

Universitas Gadjah Mada

ChemistrySelect

In silico Approach for Design, Synthesis and Biological Evaluation of Tioxanthone Derivatives as Potential Anticancer Agents

The investigation of thioxanthones involved molecular docking, molecular dynamics simulation, synthesis, and evaluation of their potential as anticancer agents. Molecular docking analyses indicated that 2,4‐dichloro‐1,3‐dihydroxythioxanthone and 2,4‐dibromo‐1,3‐dihydroxythioxanthone had lower binding energies and 4‐bromo‐1,3‐dihydroxythioxanthone had the similar binding energy compared to erlotinib. In 50 ns molecular dynamics simulation, 2,4‐dichloro‐1,3‐dihydroxythioxanthone and 2,4‐dibromo‐1,3‐dihydroxythioxanthone complex exhibited more stability than 4‐bromo‐1,3‐dihydroxythioxanthone and erlotinib, while it had similar stability with doxorubicin. These compounds comply the Lipinski's rule parameters and the minimum required parameters of ADMET. The evaluated anticancer activity of 2,4‐dichloro‐1,3‐dihydroxythioxanthone and 2,4‐dibromo‐1,3‐dihydroxythioxanthone revealed …

Sajjad Ahmad

Sajjad Ahmad

Quaid-i-Azam University

ChemistrySelect

Biological Activities, DFT and Molecular Docking Studies of Novel Schiff Bases Derived from Sulfamethoxypyridazine

The present study reported the synthesis and biological activities of sulfamethoxypyridazine (SMPR) Schiff bases (SBs) with different aromatic aldehydes. The antimicrobial potential of SBs against various pathogenic strains (S. epidermidis, E. coli, S. agalactiae, S. aureus, S. typhi, K. pneumoniae, C. albicans, and C. tropicalis) was explored by disc diffusion method. The antidiabetic potential was monitored by inhibition of α‐amylase, α‐glucosidase, and anti‐inflammatory activity was studied by protein denaturation assay. The binding of protein with SBs was determined by MOE docking. The synthesized SBs reveal significant antimicrobial potential against all strains (p values<0.0001) better than the parent drug SMPR but less than amoxicillin. The synthesized SBs exhibited reasonable inhibition potential against α‐glucosidase, α‐amylase, and anti‐inflammatory activity. The derivative 10 a depicted antioxidant (IC …

Siti Munirah Mohd Faudzi

Siti Munirah Mohd Faudzi

Universiti Putra Malaysia

ChemistrySelect

Synthesis of a Series of Quinoxaline Derivatives and Their Antibacterial Effectiveness Against Pathogenic Bacteria

The pharmacological importance of quinoxaline derivatives in antibacterial research is well recognized. This study focuses on the synthesis of new 2,3‐dichloroquinoxaline derivatives containing thioether/ether groups to explore their potential as potent antibacterial agents against various pathogenic bacteria. Most of the compounds exhibited significant antibacterial properties comparable to the standard drug chlorhexidine (CHX). The derivatives of 2‐chloro‐3‐(arylthiol)quinoxaline demonstrated efficacy against Escherichia coli with minimum inhibitory concentrations (MIC) of 2.5 mg/mL and minimum bactericidal concentrations (MBC) of 2.5 to 5.0 mg/mL. These derivatives also showed similar sensitivity to Bacillus pumilus. In addition, molecular docking simulations were performed to investigate the interaction between the synthesized compounds and the DNA gyrase protein (PDB ID: 1KZN), a target for …

Nilwala Kottegoda

Nilwala Kottegoda

University of Sri Jayewardenepura

ChemistrySelect

Low‐Carbon‐Footprint Plasma‐Functionalized Coconut‐Coir‐Based Porous Carbon as an Efficient and Sustainable Adsorbent

Herein, the surface of pyrolyzed coconut coir (PCC) dust has been functionalized using atmospheric plasma under non‐equilibrium conditions without utilizing vacuum chambers. The reactive species present in the plasma such as, molecular ions, electrons, and radicals interact with PCC's surface, leading to the introduction of epoxy, carbonyl and amino functional groups on carbon surface. The resulting plasma functionalized carbon (PFC) material was characterized using several advanced material characterization techniques, including PXRD, FTIR, XPS, N2 BET specific surface area, SEM and TEM imaging techniques, etc. Moreover, it has been used in diverse applications in toxic gas removal (CO2, CO, NOx), fluoride (F−) removal from drinking water and cationic organic dye (methylene blue–MB) removal. The reported method for synthesis of functional carbon introduces a platform technology for low carbon …

Oguzhan Gunduz

Oguzhan Gunduz

Marmara Üniversitesi

ChemistrySelect

Mapping the Influence of Solvent Composition over the Characteristics of Polylactic Acid Nanofibers Fabricated by Electrospinning

This study investigated the solubility of poly(lactic acid) (PLA) in various solvents (to achieve an 8 % (w/v) polymer solution) and its impact on the morphology of electrospun PLA nanofibers. Several solvents, such as dichloromethane (DCM), chloroform (CHL), tetrahydrofuran (THF), acetone (AC), acetonitrile (ACTNR), dimethylformamide (DMF), dimethylacetamide (DMAc), ethylene glycol (ETGLY), distilled water (WATER), methanol (MEOH), formic acid (FA), and n‐hexane (NHX) were used in their pure and binary forms at several ratios (4 : 1, 2 : 1, 1 : 1, 1 : 2, 1 : 3, and 1 : 4). The study aims to explore the correlation between PLA solubility and its electrospinnability using solvents mapped from the Teas graph across different parameter zones and chemical groups. Hansen solubility parameters, including dispersion cohesion fractional solubility parameter (fd), the polar cohesion fractional solubility …