Volumetric and infrared studies of carbon monoxide adsorption on silica-supported iron catalysts characterised by thermogravimetric analysis and X-ray diffraction

The chemistry and the kinetics of the reduction of calcium containing CaFeSO and Ca2FeCuSO3) oxysulfides in a mixture of flowing gases that contains (75% CO) carbon monoxide and argon have been investigated by thermogravimetric analysis and X-ray diffraction. Experiments were carried out on the synthesized samples by heating up to 1270 K with heating rates of 5-20 K/min. The Netzsch Thermokinetics program was used for the analysis of the experimental data. Kinetic parameters of reduction processes are determined.

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Valorization of Byproducts of Hemp Multipurpose Crop: Short Non-Aligned Bast Fibers as a Source of Nanocellulose

Molecules ◽

10.3390/molecules26164723 ◽

2021 ◽

Vol 26 (16) ◽

pp. 4723

Author(s):

Sara Dalle Vacche ◽

Vijayaletchumy Karunakaran ◽

Alessia Patrucco ◽

Marina Zoccola ◽

Loreleï Douard ◽

...

Keyword(s):

Infrared Spectroscopy ◽

Thermogravimetric Analysis ◽

Cannabis Sativa ◽

Crystallinity Index ◽

Residual Lignin ◽

Chemical Pretreatment ◽

X Ray Diffraction ◽

X Ray ◽

Bast Fibers ◽

Seed Maturity

Nanocellulose was extracted from short bast fibers, from hemp (Cannabis sativa L.) plants harvested at seed maturity, non-retted, and mechanically decorticated in a defibering apparatus, giving non-aligned fibers. A chemical pretreatment with NaOH and HCl allowed the removal of most of the non-cellulosic components of the fibers. No bleaching was performed. The chemically pretreated fibers were then refined in a beater and treated with a cellulase enzyme, followed by mechanical defibrillation in an ultrafine friction grinder. The fibers were characterized by microscopy, infrared spectroscopy, thermogravimetric analysis and X-ray diffraction after each step of the process to understand the evolution of their morphology and composition. The obtained nanocellulose suspension was composed of short nanofibrils with widths of 5–12 nm, stacks of nanofibrils with widths of 20–200 nm, and some larger fibers. The crystallinity index was found to increase from 74% for the raw fibers to 80% for the nanocellulose. The nanocellulose retained a yellowish color, indicating the presence of some residual lignin. The properties of the nanopaper prepared with the hemp nanocellulose were similar to those of nanopapers prepared with wood pulp-derived rod-like nanofibrils.

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A MOF based on a lead(II) 2-oxido-6-methylpyridine-4-carboxylate network

Zeitschrift für Naturforschung B ◽

10.1515/znb-2019-0208 ◽

2020 ◽

Vol 75 (4) ◽

pp. 365-369

Author(s):

Long Tang ◽

Yu Pei Fu ◽

Na Cui ◽

Ji Jiang Wang ◽

Xiang Yang Hou ◽

...

Keyword(s):

Crystal Structure ◽

Solid State ◽

Carboxylic Acid ◽

Thermogravimetric Analysis ◽

Metal Organic Framework ◽

X Ray Diffraction ◽

X Ray ◽

Connected Node ◽

Metal Organic ◽

Solid State Fluorescence

AbstractA new metal-organic framework, [Pb(hmpcaH)2]n (1), has been hydrothermally synthesized from Pb(OAc)2 · 3H2O and 2-hydroxy-6-methylpyridine-4-carboxylic acid (hmpcaH2; 2), and characterized by IR spectroscopy, elemental and thermogravimetric analysis, and single-crystal X-ray diffraction. In complex 1, each hmpcaH− ligand represents a three-connected node to combine with the hexacoordinated Pb(II) ions, generating a 3D binodal (3,6)-connected ant network. The crystal structure of 2 was determined. The solid-state fluorescence properties of 1 and 2 were investigated.

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Influence of the Presence of Different Alkali Cations and the Amount of Fe(CN)6 Vacancies on CO2 Adsorption on Copper Hexacyanoferrates

Materials ◽

10.3390/ma12203371 ◽

2019 ◽

Vol 12 (20) ◽

pp. 3371 ◽

Cited By ~ 1

Author(s):

Svensson ◽

Grins ◽

Eklöf ◽

Eriksson ◽

Wardecki ◽

...

Keyword(s):

Thermogravimetric Analysis ◽

Prussian Blue ◽

Co2 Adsorption ◽

X Ray Diffraction ◽

Alkali Cations ◽

Prussian Blue Analogue ◽

X Ray ◽

Infra Red ◽

Adsorption Desorption ◽

Adsorption Capability

The CO2 adsorption on various Prussian blue analogue hexacyanoferrates was evaluated by thermogravimetric analysis. Compositions of prepared phases were verified by energy-dispersive X-ray spectroscopy, infra-red spectroscopy and powder X-ray diffraction. The influence of different alkali cations in the cubic Fm3m structures was investigated for nominal compositions A2/3Cu[Fe(CN)6]2/3 with A = vacant, Li, Na, K, Rb, Cs. The Rb and Cs compounds show the highest CO2 adsorption per unit cell, 3.3 molecules of CO2 at 20 C and 1 bar, while in terms of mmol/g the Na compound exhibits the highest adsorption capability, 3.8 mmol/g at 20 C and 1 bar. The fastest adsorption/desorption is exhibited by the A-cation free compound and the Li compound. The influence of the amount of Fe(CN)6 vacancies were assessed by determining the CO2 adsorption capabilities of Cu[Fe(CN)6]1/2 (Fm3m symmetry, nominally 50% vacancies), KCu[Fe(CN)6]3/4 (Fm3m symmetry, nominally 25% vacancies), and CsCu[Fe(CN)6] (I-4m2 symmetry, nominally 0% vacancies). Higher adsorption was, as expected, shown on compounds with higher vacancy concentrations.

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X-Ray diffraction and infrared studies on the effect of thermal treatments on cotton celluloses I and II

Journal of Polymer Science Polymer Letters Edition ◽

10.1002/pol.1981.130190405 ◽

1981 ◽

Vol 19 (4) ◽

pp. 183-187 ◽

Cited By ~ 12

Author(s):

M. A. Moharram ◽

T. Z. Abou El Nasr ◽

Nagwa Abdel Hakeem

Keyword(s):

Thermal Treatments ◽

X Ray Diffraction ◽

X Ray ◽

Infrared Studies

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Study of Thermal Behaviour of EPDM/SBR Blends and Carbon Nanocoatings Deposited by Sputtering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.875.116 ◽

2021 ◽

Vol 875 ◽

pp. 116-120

Author(s):

Muhammad Alamgir ◽

Faizan Ali Ghauri ◽

Waheed Qamar Khan ◽

Sajawal Rasheed ◽

Muhammad Sarfraz Nawaz ◽

...

Keyword(s):

Thermal Stability ◽

Weight Loss ◽

Thermogravimetric Analysis ◽

Thermal Behavior ◽

Thermal Behaviour ◽

X Ray Diffraction ◽

X Ray ◽

Thermal Stability Of

In this study, the effect of SBR concentration (10 Phr, 20 Phr & 30 Phr ) on the thermal behavior of EPDM/SBR blends was studied. Thermogravimetric analysis (TGA) was used to check weight loss of samples as function of temperature by heating upto 600°C. X-ray diffraction (XRD) was performed to determine quality and % crystallinity of the elastomer blends. It was seen that % crystallinity improved with an increase in the content of SBR in EPDM/SBR blends. TGA revealed that the thermal stability of EPDM/SBR blends has improved by 17% than neat EPDM. Carbon nano-coatings produced by sputtering have no beneficial influence on thermal behaviour of elastomers.

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Influence of Organophilization Process Variables in Bentonite Clays from Cubati-PB

Materials Science Forum ◽

10.4028/www.scientific.net/msf.727-728.1467 ◽

2012 ◽

Vol 727-728 ◽

pp. 1467-1472

Author(s):

Carla Dantas da Silva ◽

Rosa do Carmo de Oliveira Lima ◽

Julliana Marques Rocha Costa ◽

Gelmires Araújo Neves ◽

Heber Carlos Ferreira

Keyword(s):

Thermogravimetric Analysis ◽

Bentonite Clay ◽

Laser Diffraction ◽

Ionic Surfactants ◽

Organic Media ◽

Process Variables ◽

X Ray Diffraction ◽

X Ray ◽

Bentonite Clays ◽

Sodium Form

This work aims at the development of organoclay from two varieties of bentonite for use in organic media using ionic surfactants, studying the influence of process variables in the organophilization process. We used the following materials: natural bentonite clay from Cubati-PB District, and the ionic quaternary ammonium salt: Praepagen WB® with 45% active matter. The clays were benefited and then turned into sodium form and subsequently into organoclays. The bentonites were characterized by laser diffraction (GA) X-ray fluorescence chemical composition (EDX), thermogravimetric analysis (TGA), thermogravimetry (DTA) and X-ray diffraction (XRD). The organoclays were characterized by (XRD) thermogravimetric analysis (TGA) and thermogravimetry (DTA). The results showed that the clay has potential for application in the organophilization process and that there is influence of process variables.

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Powder X-ray diffraction study of disilver(1+) pentacyanonitrosylferrate(2−)

Powder Diffraction ◽

10.1017/s0885715600010563 ◽

1999 ◽

Vol 14 (3) ◽

pp. 219-221 ◽

Cited By ~ 2

Author(s):

V. Venegas ◽

A. Gómez ◽

E. Reguera

Keyword(s):

Crystal Structure ◽

Thermogravimetric Analysis ◽

Diffraction Study ◽

Powder Diffraction ◽

Lattice Parameters ◽

X Ray Diffraction ◽

Density Measurements ◽

X Ray

The crystal structure of disilver(1+) pentacyanonitrosylferrate(2−) was studied by X-ray powder diffraction. IR and Mössbauer spectroscopies, thermogravimetric analysis and density measurements were also carried out. This compound is monoclinic, and its lattice parameters are: a=10.986(3) Å, b=6.4080(10) Å, c=7.4545(19) Å, α=δ=90°, β=102.54°(2).

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