Synthesis of Uniform Mesoporous Zeolite ZSM-5 Catalyst for Friedel-Crafts Acylation

This work highlights how the treatment of ZSM-5 (parent Zeolite Socony Mobil–5, Si/Al = 23) with different surfactant templates and alkaline solution, improved the catalytic performance in the Friedel-Crafts acylation of anisole with a propionic anhydride to obtain p-methoxypropiophenone. The modified microporous to mesoporous zeolite catalysts were characterized using different analytical techniques, including X-ray diffraction (XRD), nitrogen porosimetry, Fourier-transform infrared spectroscopy (FT-IR), temperature-programmed desorption (ammonia-TPD) and field emission scanning electron microscopy (FE-SEM) to analyze the crystallographic structure, surface acidity, surface area, porosity, morphology, and particle size. The results showed that the formed mesoporous zeolite by NaOH solution had smaller mesopores (ca. 3.7 nm) as compared to the mesoporous zeolites obtained by surfactant templates, such as, CTAB (ca. 14.9 nm), TPAOH (ca. 11.1 nm) and mixture of CTAB/TPAOH (ca. 15.2 nm). The catalytic acylation reaction was conducted in a batch glass reactor at various temperatures and the products were analyzed using off-line gas chromatography–mass spectrometry (GC-MS). It was found that the activity of treated ZSM-5 with mixed surfactant templates (CTAB/TPAOH) exhibited enhanced selectivity towards the main product (p-methoxypropiophenone) by a factor 1.7 or higher than unmodified ZSM-5 due to its increased surface area by 1.5 times and enhanced acid sites.

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Effect of Acid Treatment on the Properties of Zeolite Catalyst for Straight-Run Gasoline Upgrading

10.21926/cr.2104004 ◽

2021 ◽

Vol 1 (4) ◽

pp. 1-1

Author(s):

Ludmila Velichkina ◽

◽

Yakov Barbashin ◽

Alexander Vosmerikov ◽

◽

...

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Acid Treatment ◽

Catalytic Properties ◽

Fixed Bed ◽

Acid Sites ◽

Gasoline Fraction ◽

Zeolite Catalysts ◽

Acidic Properties

The objective of this research was to analyze the effect of different concentrations of nitric and hydrochloric acids on the structural, acidic, and catalytic properties of a post-synthetic treated ZSM-5 type zeolite at various temperatures. The properties of zeolite catalysts were determined using different methods, such as the Brunauer-Emmett-Teller (BET) method for specific surface area, temperature-programmed desorption (TPD) of ammonia method for acidic properties, and a flow-through unit with fixed bed catalyst (with upgrading straight-run gasoline fraction of oil) for catalytic activities of initial zeolite and acid-treated samples. The structural and acidic properties of both untreated and treated zeolites were investigated, and the effect of acid treatment on the catalytic properties of the samples in the course of upgrading the straight-run gasoline fraction of oil was determined. The post-synthetic treatment with aqueous nitric acid increased the specific surface area and volume of micropores of ZSM-5 zeolite, while the treatment with aqueous hydrochloric acid led to the formation of mesopores. Acid treatments of zeolite decreased the number of acid sites, mainly due to diminished concentration of low-temperature sites. The yield of liquid products in the conversion of straight-run gasoline fraction of oil, i.e., generation of high-octane gasolines with improved environmental features, was increased using acid-treated zeolites, which was due to the decrease in arene content.

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Effect of Mg/Al2O3 and Calcination Temperature on the Catalytic Decomposition of HFC-134a

Catalysts ◽

10.3390/catal9030270 ◽

2019 ◽

Vol 9 (3) ◽

pp. 270 ◽

Cited By ~ 1

Author(s):

Caroline Andrew Swamidoss ◽

Mahshab Sheraz ◽

Ali Anus ◽

Sangjae Jeong ◽

Young-Kwon Park ◽

...

Keyword(s):

Surface Area ◽

Calcination Temperature ◽

Flow Reactor ◽

Coke Formation ◽

Plug Flow ◽

Strong Acid ◽

Acid Sites ◽

Gas Chromatography Mass Spectrometry ◽

Hfc 134A ◽

Strong Acid Sites

This paper evaluated the effect of calcination temperature and the use of Mg/Al2O3 on the decomposition of HFC-134a. Two commercialized catalysts, Al2O3 and Mg/Al2O3, were calcined at two different temperatures (500 and 650 °C) and their physicochemical characteristics were examined by X-ray diffraction, Brunauer–Emmett–Teller analysis, and the temperature-programed desorption of ammonia and carbon dioxide analysis. The results show that, in comparison to Al2O3, 5% Mg/Al2O3 exhibited a larger Brunauer–Emmett–Teller surface area and higher acidity. The relative amount of strong acid sites of the catalysts decreased with increasing calcination temperature. Although a more than 90% decomposition rate of HFC-134a was achieved over all catalysts during the sequential decomposition test of HFC-134a using a vertical plug flow reactor connected directly to a gas chromatography/mass spectrometry system, the lifetime of the catalyst differed according to the catalyst type. Compared to Al2O3, Mg/Al2O3 revealed a longer lifetime and less coke formation due to the increased Brunauer–Emmett–Teller surface area and weak Lewis acid sites and basic sites arising from Mg impregnation. Higher temperature calcination extended the catalyst lifetime with the formation of less coke due to the smaller number of strong acid sites, which can lead to severe coke formation. A valuable by-product, trifluoroethylene, was formed as a result of the decomposition. Based on the experimental results, a reaction is proposed which reasonably explains the decomposition reaction.

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KARAKTERISASI KATALIS BATU PADAS LEDGESTONE TERAKTIVASI ASAM DAN APLIKASINYA PADA PEMBUATAN BIODIESEL DARI MINYAK JELANTAH

Jurnal Kimia ◽

10.24843/jchem.2016.v10.i01.p05 ◽

2016 ◽

Author(s):

Ika Juliana ◽

Ida Ayu Gede Widihati ◽

Oka Ratnayani

Keyword(s):

Cation Exchange ◽

Surface Area ◽

Cation Exchange Capacity ◽

Active Sites ◽

Surface Acidity ◽

Acid Value ◽

Exchange Capacity ◽

Gas Chromatography Mass Spectrometry ◽

Acid Activation

This research aims to improve characteristics of ledgestone catalyst by using acid activation with various concentrations. The acid used for activation was H2SO4 with concentrations of 1, 2 and 3M. The characterization of catalysts was carried out by acid-base titration method to determine the surface acidity, methylene blue adsorption to measure the spesific surface area of ??the catalyst, and the NH4OAc extraction method to measure the value of cation exchange capacity of the catalyst. Ledgestone catalyst with the best character was applied to convert waste cooking oil into biodiesel. The characterization of biodiesel was carried out by densitometry to determine the density of biodiesel, Oswald viskosimetry to measure the viscosity, and Gas Chromatography-Mass Spectrometry (GCMS) to determine the composition of chemical compounds of the biodiesel. The results showed that the concentration of acid used to activate ledgestone catalyst with the best character was 1M. This acid-activated ledgestone (catalyst A1) had a value of surface acidity, surface area, active sites number, and high cation exchange capacity were 0.3530 ± 0.0011 mmol / gram and35.7581 m2/gram, 2.1258 x 1020 atoms/gram, and 5.88 me/100 g, respectively. The concentration of catalyst A1 producing the highest biodiesel yield was 1% w/v. The produced biodiesel was 74,71% with 0.02% FFA, acid value of 0.0438 mg KOH/gram biodiesel, density of 0.7850 g/mL, kinematic viscosity of 0.4650 cSt. Two major compounds of the biodiesel were methyl hexadecanoate with area of 71.84% and cis methyl-9-octadecenoate with area of 28.16%.

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Comparison of Three Approaches to Assess the Flavour Characteristics of Scotch Whisky Spirit

Applied Sciences ◽

10.3390/app11041410 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1410

Author(s):

Martina Daute ◽

Frances Jack ◽

Irene Baxter ◽

Barry Harrison ◽

John Grigor ◽

...

Keyword(s):

Mass Spectrometry ◽

Descriptive Analysis ◽

Analytical Techniques ◽

Gas Chromatography Mass Spectrometry ◽

Multiple Factor Analysis ◽

Quantitative Descriptive Analysis ◽

Yeast Strains ◽

Quantitative Descriptive ◽

Scotch Whisky ◽

Multiple Factor

This study compared the use of three sensory and analytical techniques: Quantitative Descriptive Analysis (QDA), Napping, and Gas Chromatography-Mass Spectrometry (GC-MS) for the assessment of flavour in nine unmatured whisky spirits produced using different yeasts. Hierarchical Multiple Factor Analysis (HMFA) showed a similar pattern of sample discrimination (RV scores: 0.895–0.927) across the techniques: spirits were mostly separated by their Alcohol by Volume (ABV). Low ABV spirits tended to have heavier flavour characteristics (feinty, cereal, sour, oily, sulphury) than high ABV spirits, which were lighter in character (fruity, sweet, floral, solventy, soapy). QDA differentiated best between low ABV spirits and GC-MS between high ABV spirits, with Napping having the lowest resolution. QDA was time-consuming but provided quantitative flavour profiles of each spirit that could be readily compared. Napping, although quicker, gave an overview of the flavour differences of the spirits, while GC-MS provided semi-quantitative ratios of 96 flavour compounds for differentiating between spirits. Ester, arenes and certain alcohols were found in higher concentrations in high ABV spirits and other alcohols and aldehydes in low ABV spirits. The most comprehensive insights on spirit flavour differences produced by different yeast strains are obtained through the application of a combination of approaches.

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Simple Equations Pertaining to the Particle Number and Surface Area of Metallic, Polymeric, Lipidic and Vesicular Nanocarriers

Scientia Pharmaceutica ◽

10.3390/scipharm89020015 ◽

2021 ◽

Vol 89 (2) ◽

pp. 15

Author(s):

M. R. Mozafari ◽

E. Mazaheri ◽

K. Dormiani

Keyword(s):

Drug Delivery ◽

Surface Area ◽

Particle Number ◽

Analytical Techniques ◽

Metallic Particles ◽

Nutraceutical Compounds ◽

Mathematical Formulas ◽

Simple Equations

Introduction: Bioactive encapsulation and drug delivery systems have already found their way to the market as efficient therapeutics to combat infections, viral diseases and different types of cancer. The fields of food fortification, nutraceutical supplementation and cosmeceuticals have also been getting the benefit of encapsulation technologies. Aim: Successful formulation of such therapeutic and nutraceutical compounds requires thorough analysis and assessment of certain characteristics including particle number and surface area without the need to employ sophisticated analytical techniques. Solution: Here we present simple mathematical formulas and equations used in the research and development of drug delivery and controlled release systems employed for bioactive encapsulation and targeting the sites of infection and cancer in vitro and in vivo. Systems covered in this entry include lipidic vesicles, polymeric capsules, metallic particles as well as surfactant- and tocopherol-based micro- and nanocarriers.

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Solvent-Free Synthesis of SAPO-34 Zeolite with Tunable SiO2/Al2O3 Ratios for Efficient Catalytic Cracking of 1-Butene

Catalysts ◽

10.3390/catal11070835 ◽

2021 ◽

Vol 11 (7) ◽

pp. 835

Author(s):

Xia Xiao ◽

Zhongliang Xu ◽

Peng Wang ◽

Xinfei Liu ◽

Xiaoqiang Fan ◽

...

Keyword(s):

Catalytic Cracking ◽

Acid Sites ◽

Solvent Free ◽

Zeolite Catalysts ◽

Light Olefins ◽

Molar Ratio ◽

Coordination Environment ◽

Starting Mixture ◽

Synthesis Methodology ◽

Solvent Free Synthesis

Solvent-free synthesis methodology is a promising technique for the green and sustainable preparation of zeolites materials. In this work, a solvent-free route was developed to synthesize SAPO-34 zeolite. The characterization results indicated that the crystal size, texture properties, acidity and Si coordination environment of the resulting SAPO-34 were tuned by adjusting the SiO2/Al2O3 molar ratio in the starting mixture. Moreover, the acidity of SAPO-34 zeolite was found to depend on the Si coordination environment, which was consistent with that of SAPO-34 zeolite synthesized by the hydrothermal method. At an SiO2/Al2O3 ratio of 0.6, the SP-0.6 sample exhibited the highest conversion of 1-butene (82.8%) and a satisfactory yield of light olefins (51.6%) in the catalytic cracking of 1-butene, which was attributed to the synergistic effect of the large SBET (425 m2/g) and the abundant acid sites (1.82 mmol/g). This work provides a new opportunity for the design of efficient zeolite catalysts for industrially important reactions.

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Effect of surface acidity on the catalytic activity and deactivation of supported sulfonic acids during dehydration of methanol to DME

New Journal of Chemistry ◽

10.1039/d0nj00229a ◽

2020 ◽

Vol 44 (39) ◽

pp. 16810-16820

Author(s):

Rosanna Viscardi ◽

Vincenzo Barbarossa ◽

Daniele Mirabile Gattia ◽

Raimondo Maggi ◽

Giovanni Maestri ◽

...

Keyword(s):

Catalytic Activity ◽

Sulfonic Acid ◽

Water Resistance ◽

Surface Acidity ◽

Acid Catalyst ◽

Acid Sites ◽

Sulfonic Acids ◽

Effect Of Surface

Superiorty of the supported sulfonic acid catalyst in terms of the water resistance and efficiency of the acid sites compared to the commercial reference.

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Characterization and Catalytic Behaviour of Co3(PO4)2–AlPO4 Catalysts

Adsorption Science & Technology ◽

10.1177/026361749801600405 ◽

1998 ◽

Vol 16 (4) ◽

pp. 285-293 ◽

Cited By ~ 5

Author(s):

M.R. Mostafa ◽

F.Sh. Ahmed

Keyword(s):

Pore Radius ◽

Surface Acidity ◽

Total Pore Volume ◽

Textural Properties ◽

Acid Sites ◽

Adsorption Of Nitrogen ◽

Amorphous Structures ◽

Ft Ir ◽

Catalytic Behaviour ◽

The Mean

Co3(PO4)2, AlPO4 and the binary system Co3(PO4)2-AlPO4 with different compositions were prepared by the coprecipitation method. The structural properties of these samples were determined using XRD, DTA and FT-IR techniques. The textural properties were determined from the adsorption of nitrogen at 77 K. The surface acidity was measured by a calorimetric titration method. The samples were tested as catalysts in the dehydration of ethanol and isopropanol using a pulse microcatalytic technique. The data obtained from XRD and FT-IR indicate the amorphous structures of the prepared catalysts. An increase in Co3(PO4)2 content led to a decrease in the surface area and in the total pore volume and an increase in the mean pore radius. The surface acidity of the catalyst depends on the chemical composition; the surface acidity increased with an increase in the AlPO4 content. The dehydration temperature and the distribution of acid sites are important parameters in determining the selectivity and activity of the catalyst.

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Conversion of jet biofuel range hydrocarbons from palm oil over zeolite hybrid catalyst

Nanomaterials and Nanotechnology ◽

10.1177/1847980420981536 ◽

2021 ◽

Vol 11 ◽

pp. 184798042098153

Author(s):

Norsahika Mohd Basir ◽

Norkhalizatul Akmal Mohd Jamil ◽

Halimaton Hamdan

Keyword(s):

Palm Oil ◽

Aromatic Hydrocarbons ◽

Zeolite Y ◽

Zeolite Catalysts ◽

Gas Chromatography Mass Spectrometry ◽

Chemical Compositions ◽

Hybrid Catalyst ◽

X Ray Diffraction ◽

Temperature Programmed ◽

Reaction Routes

The catalytic conversion of palm oil was carried out over four zeolite catalysts—Y, ZSM-5, Y-ZSM-5 hybrid, and Y/ZSM-5 composite—to produce jet biofuel with high amount of alkanes and low amount of aromatic hydrocarbons. The zeolite Y-ZSM-5 hybrid catalyst was synthesized using crystalline zeolite Y as the seed for the growth of zeolite ZSM-5. Synthesized zeolite catalysts were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, and temperature programmed desorption of ammonia, while the chemical compositions of the jet biofuel were analyzed by gas chromatography-mass spectrometry (GC-MS). The conversion of palm oil over zeolite Y resulted in the highest yield (42 wt%) of jet biofuel: a high selectivity of jet range alkanes (51%) and a low selectivity of jet range aromatic hydrocarbons (25%). Zeolite Y-ZSM-5 hybrid catalyst produced a decreased percentage of jet range alkane (30%) and a significant increase in the selectivity of aromatic hydrocarbons (57%). The highest conversion of palm oil to hydrocarbon compounds was achieved by zeolite Y-ZSM-5 hybrid catalyst (99%), followed by zeolite Y/ZSM-5 composite (96%), zeolite Y (91%), and zeolite ZSM-5 (74%). The reaction routes for converting palm oil to jet biofuel involve deoxygenation of fatty acids into C15–C18 alkanes via decarboxylation and decarbonylation, catalytic cracking into C8–C14 alkanes, and cycloalkanes as well as aromatization into aromatic hydrocarbon.

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Cellular fatty acids of Peptococcus variabilis and Peptostreptococcus anaerobius

Journal of Clinical Microbiology ◽

10.1128/jcm.5.6.665-667.1977 ◽

1977 ◽

Vol 5 (6) ◽

pp. 665-667

Author(s):

C W Moss ◽

M A Lambert ◽

G L Lombard

Keyword(s):

Mass Spectrometry ◽

Fatty Acids ◽

Gas Chromatography ◽

Analytical Techniques ◽

Gas Chromatography Mass Spectrometry ◽

Cellular Fatty Acids ◽

Chromatography Mass Spectrometry ◽

Branched Chain

Cellular fatty acids of Peptococcus variables and Peptostreptococcus anaerobius were identified by gas chromatography, mass spectrometry, and associated analytical techniques. Iso- and anteiso-branched-chain acids were major components in both species.

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