Friedel–Crafts alkylation of 4-hydroxycoumarin over silica-bonded 1,4-diaza-bicyclo[2.2.2] octane-sulfonic acid chloride as nanostructured heterogeneous catalyst

2017 ◽  
Vol 95 (1) ◽  
pp. 16-21 ◽  
Author(s):  
Ehsan Noroozizadeh ◽  
Ahmad Reza Moosavi-Zare ◽  
Mohammad Ali Zolfigol ◽  
Abdolkarim Zare ◽  
Mahmoud Zarei
Keyword(s):  
Heterogeneous Catalyst ◽  
Acid Chloride ◽  
Sulfonic Acid ◽  
Condensation Reaction ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
Efficient Catalyst ◽  
X Ray ◽  
Solvent Free Conditions

A novel nanostructured heterogeneous catalyst, namely silica-bonded 1,4-diaza-bicyclo[2.2.2]octane-sulfonic acid chloride (SBDBSAC), has been synthesized and fully characterized by several techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), differential thermal gravimetric (DTG), scanning electron microscope (SEM), and energy dispersive X-ray analysis (EDX). Afterward, the nanostructured catalyst was utilized as an efficient catalyst for the synthesis of bis-coumarin derivatives by the condensation reaction of arylaldehydes with 4-hydroxycoumarin at 70 °C under solvent-free conditions.

scholarly journals Rapid four-component synthesis of dihydropyrano[2,3-c]pyrazoles using nano-eggshell/Ti(IV) as a highly compatible natural based catalyst

BMC Chemistry ◽  
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Arefeh Dehghani Tafti ◽  
Bi Bi Fatemeh Mirjalili ◽  
Abdolhamid Bamoniri ◽  
Naeimeh Salehi
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Reaction Times ◽  
Diffraction Field ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solvent Free Conditions ◽  
High Yields ◽  
Work Up

AbstractNano-eggshell/Ti(IV) as a novel naturally based catalyst was prepared, characterized and applied for the synthesis of dihydropyrano[2,3-c]pyrazole derivatives. The characterization of nano-eggshell/Ti(IV) was performed using Fourier Transform Infrared spectroscopy, X-ray Diffraction, Field Emission Scanning Electron Microscopy, Energy-Dispersive X-ray Spectroscopy, and Thermo Gravimetric Analysis. Dihydropyrano[2,3-c]pyrazoles were synthesized in the presence of nano-eggshell/Ti(IV) via a four component reaction of aldehydes, ethyl acetoacetate, malononitrile and hydrazine hydrate at room temperature under solvent free conditions. The principal affairs of this procedure are mild condition, short reaction times, easy work-up, high yields, reusability of the catalyst and the absence of toxic organic solvents.

Synthesis of Indole Derivatives Using Biosynthesized ZnO-CaO Nanoparticles as an Efficient Catalyst

2021 ◽  
Vol 66 ◽  
pp. 61-71
Author(s):  
Tahereh Heidarzadeh ◽  
Navabeh Nami ◽  
Daryoush Zareyee
Keyword(s):  
Electron Microscopy ◽  
Indole Derivatives ◽  
X Ray Diffraction ◽  
Efficient Catalyst ◽  
X Ray ◽  
Transmission Electron ◽  
Solvent Free Conditions ◽  
Ft Ir ◽  
Eggshell Waste ◽  
Aromatic And Aliphatic Amines

The principal aim of this research is using biosynthesized ZnO-CaO nanoparticles (NPs) for preparation of indole derivatives. ZnO-CaO NPs have been prepared using Zn(CH3COO)2 and eggshell waste powder in solvent-free conditions. Morphology and structure of NPs were determined by FT-IR, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive spectra (EDS). It was used as a highly efficient catalyst for the synthesis of indole derivatives. Some indole derivatives were synthesized by the reaction of indole, formaldehyde, aromatic and aliphatic amines in the presence of ZnO-CaO NPs (5 mol%) in ethanol under reflux conditions. The assigned structure was further established by CHN analyses, NMR, and FT-IR spectra. Because of excellent capacity, the exceedingly simple workup and good yield, eco-friendly catalyst ZnO-CaO NPs were proved to be a good catalyst for this reaction.

Synthesis of Novel Carbon Spheres and Study on Graphitization Process

2013 ◽  
Vol 634-638 ◽  
pp. 2293-2296
Author(s):  
Ai Li Ma ◽  
Cheng Qian Li ◽  
Wu Qing Du ◽  
Jie Chang
Keyword(s):  
High Temperature ◽  
Microwave Plasma ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Carbon Spheres ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cvd Method ◽  
Graphitization Degree ◽  
Scanning Electron

In this paper, carbon spheres were synthesized by CVD method. These carbon spheres exhibit diameters of about 200 nm. Thermal gravimetric analysis indicated the good stability in high temperature of the carbon spheres. The products were treated by microwave plasma and high temperature vacuum heat treatments respectively. The products were characterized by X-ray diffraction, Raman spectroscopy and Field Emission Scanning Electron Microscope. The study indicated that the original products, with perfect morphology and low graphitization degree, were converted to crystal. The different techniques were considered for the influence on the graphitization degree.

Study on the Preparation and Properties of EVA-G-PU/OMMT Nanocomposites

2010 ◽  
Vol 123-125 ◽  
pp. 247-250
Author(s):  
Yu Qing Zhang ◽  
Yu Xin He ◽  
Li Zhang ◽  
Jun Xian Li
Keyword(s):  
Electron Microscopy ◽  
Mechanical Analysis ◽  
Clay Nanocomposites ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
Thermal Stabilities ◽  
X Ray ◽  
Transmission Electron ◽  
New Type

A new type of EVA-g-PU/OMMT nanocomposites was synthesized through the method of chemical modification and melt intercalation. FTIR testing showed that the PU prepolymer was grafted on EVA main chains successfully. The structures of EVA-g-PU/OMMT nanocomposites were characterized by X-ray diffraction (XRD) and by high-resolution transmission electron microscopy (HRTEM). The enhanced storage modulus of EVA-g-PU/OMMT nanocomposites was characterized by dynamic mechanical analysis (DMA). The thermal stabilities of EVA/clay nanocomposites were also studied by thermal gravimetric analysis (TGA). Mechanical testing showed that the tensile strength and tear strength of EVA-g-PU/OMMT nanocomposites were far superior to pure EVA.

scholarly journals Utilization of cajuput (Melaleuca leucadendron) twigs and sugarcane (Saccharum officinarum) bagasse agricultural waste for cellulose acetate production by environmentally friendly approach

2021 ◽  
Author(s):  
Roni Maryana ◽  
Muryanto Muryanto ◽  
Eka Triwahyuni ◽  
Oktaviani Oktaviani ◽  
Hafiizh Prasetia ◽  
...  
Keyword(s):  
Cellulose Acetate ◽  
Thermal Gravimetric Analysis ◽  
Agricultural Waste ◽  
Environmentally Friendly ◽  
Saccharum Officinarum ◽  
Hydroxyl Groups ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
X Ray

Abstract This study was carried out to investigate the extraction of cellulose acetate (CA) from cajuput (Melaleuca leucadendron) twigs and sugarcane (Saccharum officinarum) bagasse using an environmentally friendly method. At first, cellulose was extracted from cajuput twigs (CT) and sugarcane bagasse (SB) through prehydrolysis followed by soda (NaOH) pulping and elementary chlorine-free (ECF) bleaching. Later, the extracted cellulose was acetylated using iodine (I) as a catalyst. The obtained CA was characterized by Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), thermal gravimetric analysis (TGA), scanning electron microscope (SEM) and X-ray diffraction. FTIR and NMR analysis proved the replacement of free OH (hydroxyl) groups by acetyl groups. The degree of substitution (DS) showed the acetylation capability of cellulose extracted from CT and SB as well. The cellulose diameter and its crystallinity index were measured by SEM and X-ray diffraction, respectively. Furthermore, the thermal gravimetric analysis showed that CA extracted from CT and SB was thermal resistance. Therefore, CT and SB could be potential alternative resources for CA production using the mentioned method.

Catalytic acetylation of (+)-cedrol with heterogeneous catalyst H2SO4/SiO2 under solvent free conditions

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Acetic Anhydride ◽  
Heterogeneous Catalyst ◽  
Silica Gel ◽  
Solvent Free ◽  
Molar Ratio ◽  
Optimum Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solvent Free Conditions ◽  
Bet Method

Heterogeneous catalyst, H2SO4/SiO2 was synthesized by immobilizing sulfuric acid on silica gel as solid support. Silica gel was prepared from kaolin, originating from Belitung island Indonesia. The synthesized catalyst was characterized by various techniques such as X-ray diffraction, scanning electron microscopy, Fourier transform Infrared spectroscopy and BET method and was applied for the acetylation of (+)-cedrol compound using acetic anhydride under solvent free conditions. The optimum conditions for catalytic acetylation were found at 353 K for 20 h reaction period, the molar ratio (+)-cedrol/acetic anhydride 1:10 in the presence of 5%-w of catalyst converted 88,7% (+)-cedrol into cedryl acetate. Results revealed catalyst could possibly be used for cedryl acetate synthesis from (+)-cedrol.

scholarly journals Evaluation of LDPE Degradation Under Controlled Composting

2021 ◽  
Vol 20 (3) ◽  
Author(s):  
S. Singh ◽  
S. Shankar ◽  
Shikha .
Keyword(s):  
Major Change ◽  
Natural Ecosystem ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Sem Images ◽  
X Ray ◽  
Polyethylene Films ◽  
Scanning Electron

The compost burial test was performed to determine the degradation of commercially available low-density polyethylene in natural compost for a period of six months. Biodegradability of polyethylene films in compost was monitored using scanning electron microscopy (SEM), Energy dispersive X-Ray, Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and weight reduction analysis. After six months of compost exposure, a major change over the surface of LDPE was observed. SEM images clearly showed the exfoliation and cracks on the film leading to degradation. The other analysis also showed a change in the thermal properties and crystallinity of the LDPE films. The composting method could prove to be the reliable and ecological method of degrading plastic waste without hindering the natural ecosystem.

Arc Discharge Synthesis of Oxides and Carbides of Tungsten and Aluminum

2013 ◽  
Vol 8 (2) ◽  
pp. 95-101
Author(s):  
Alexey Zaikovsky ◽  
Aleksandr Fedoseev ◽  
Salavat Sakhapov ◽  
Anton Evtushenko ◽  
Marina Serebriakova ◽  
...  
Keyword(s):  
Arc Discharge ◽  
Experimental Investigations ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
X Ray ◽  
Synthesis Of Nanoparticles ◽  
Synthesized Materials ◽  
Discharge Method

Experimental investigations of the possibility of arc discharge method for synthesis of nanoparticles of oxides and carbides of tungsten and aluminum have been presented. The method is based on anode atomization of composed graphite – aluminum and graphite – WO3 electrodes. The transmitted electron microscopy, thermal gravimetric analysis and X-ray diffraction were applied for the characterization of morphology and properties of synthesized materials. It was experimentally shown the arc discharge method allows to syntheses the nanoparticles of oxides and carbides of tungsten and aluminum

Evaluation on Microstructure Stability and Thermal Resistant Ability at High Temperature of Ternary-Blended Geopolymer

2021 ◽  
Vol 321 ◽  
pp. 73-79
Author(s):  
Hoc Thang Nguyen
Keyword(s):  
High Temperature ◽  
Rice Husk Ash ◽  
High Thermal Stability ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microstructure Stability ◽  
Before And After ◽  
Materials Used

Stability of microstructure and heat resistant ability at high temperature is one of the important properties in ceramics or silicate materials which are normally exposed with fire such as refractories and insulation or other materials used in furnaces. This study used a ternary-blended geopolymer which was synthesized from an optimized mixture of red mud (RM), rice husk ash (RHA), diatomaceous earth (DE), and water glass solution (WGS) with silica modulus of 2.5. The geopolymer samples were tested thermal properties of heat resistance (%), volumetric shrinkage (%), mass loss (%) at 1000°C to evaluate thermal resistant ability. Changes of microstructure of the ternary-blended geopolymer samples were also characterized before and after exposed at high temperature using methods of X-ray diffraction (XRD), Thermogravimetric analysis or thermal gravimetric analysis (DTA-TGA), and Scanning electron microscope (SEM). The experimental results showed the ternary-blended geopolymer has high thermal stability and unchanged microstructure even at high temperatures. Hence, the geopolymer in this study is suggested to apply as an insolation with the upper limit of temperature to work at 1000°C.

Crystal structure and physical properties of a new two-dimensional zinc coordination polymer based on 1,4-bis(4-(imidazole-1-yl)benzyl)piperazine and benzophenone-2,4′-dicarboxylate ligands

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Xin-Yue Zhang ◽  
Chen Zhang ◽  
Jun Wang ◽  
Xiao-Juan Xu
Keyword(s):  
Crystal Structure ◽  
Coordination Polymer ◽  
Catalytic Properties ◽  
Gravimetric Analysis ◽  
Two Dimensional ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zinc Coordination ◽  
Oriented Parallel

Abstract A new 2-dimensional (2D) zinc(II) coordination polymer based on a flexible bis(imidazole) ligand, namely, [Zn2(BIBP)(BPDC)2·DMF] n (1) BIBP is 1,4-bis(4-(imidazole-1-yl)benzyl)piperazine and H2BPDC is benzophenone-2,4′-dicarboxylic acid), has been synthesized and characterized through single-crystal X-ray diffraction, infrared (IR) spectroscopy, and elemental and thermal gravimetric analysis. Complex 1 exhibits a 2D framework oriented parallel to [0 2 1] based on [Zn(BPDC)] n chains. The fluorescence and catalytic properties of complex 1 for the photodegradation of methylene blue were investigated.

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