Characterization of Geopolymer Materials Containing MSWI Fly Ash and Coal Fly Ash

In this work three samples of MSWI ash have been stabilized in systems containing coal fly ash and able to give geopolymers through a polycondensation reaction. Monolithic products were obtained with both MSWI ashes as received and after chloride partial removal by water washing. The polycondensation products have been characterized qualitatively by means of FT-IR spectroscopy and scanning electron microscopy (SEM) and quantitatively through the determination of the amount of reacted water and silicate. Differently from traditional cement based stabilization systems, those based on geopolymerization show a chemical behaviour almost insensitive to the presence of chlorides and sulphates in the MSWI ash. On the other hand, the microstructure is strongly affected by the content of soluble salts.

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Characterization of the Physical, Chemical, and Adsorption Properties of Coal-Fly-Ash–Hydroxyapatite Composites

Minerals ◽

10.3390/min11070774 ◽

2021 ◽

Vol 11 (7) ◽

pp. 774

Author(s):

Eleonora Sočo ◽

Dorota Papciak ◽

Magdalena M. Michel ◽

Dariusz Pająk ◽

Andżelika Domoń ◽

...

Keyword(s):

Fly Ash ◽

Coal Fly Ash ◽

Thermal Power ◽

Synthesis Conditions ◽

High Calcium ◽

Ft Ir ◽

Ir Analysis ◽

Wet Synthesis

(1) Hydroxyapatite (Hap), which can be obtained by several methods, is known to be a good adsorbent. Coal fly ash (CFA) is a commonly reused byproduct also used in environmental applications as an adsorbent. We sought to answer the following question: Can CFA be included in the method of Hap wet synthesis to produce a composite capable of adsorbing both heavy metals and dyes? (2) High calcium lignite CFA from the thermal power plant in Bełchatów (Poland) was used as the base to prepare CFA–Hap composites. Four types designated CFA–Hap1–4 were synthesized via the wet method of in situ precipitation. The synthesis conditions differed in terms of the calcium reactants used, pH, and temperature. We also investigated the equilibrium adsorption of Cu(II) and rhodamine B (RB) on CFA–Hap1–4. The data were fitted using the Langmuir, Freundlich, and Redlich–Peterson models and validated using R2 and χ2/DoF. Surface changes in CFA–Hap2 following Cu(II) and RB adsorption were assessed using SEM, SE, and FT-IR analysis. (3) The obtained composites contained hydroxyapatite (Ca/P 1.67) and aluminosilicates. The mode of Cu(II) and RB adsorption could be explained by the Redlich–Peterson model. The CFA–Hap2 obtained using CFA, Ca(NO3)2, and (NH4)2HPO4 at RT and pH 11 exhibited the highest maximal adsorption capacity: 73.6 mg Cu/g and 87.0 mg RB/g. (4) The clear advantage of chemisorption over physisorption was indicated by the Cu(II)–CFA–Hap system. The RB molecules present in the form of uncharged lactone were favorably adsorbed even on strongly deprotonated CFA–Hap surfaces.

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Synthesis of Allyl Pentaerythritol Crosslinker based Polymer Hydrogels and Determination of the Crosslink Density

Research Journal of Chemistry and Environment ◽

10.25303/2511rjce138142 ◽

2021 ◽

Vol 25 (11) ◽

pp. 138-142

Author(s):

Anamica . ◽

Poorn Prakash Pande

Keyword(s):

Crosslink Density ◽

Metal Removal ◽

Heavy Metal Removal ◽

Polymer Gels ◽

Polymer Hydrogels ◽

Swelling Capacity ◽

Ft Ir ◽

Ft Ir Spectroscopy

In this study, we report the synthesis and characterization of polymer hydrogels. The polymer gels have been prepared from acrylic acid (AA) monomer using allyl pentaerythritol as the crosslinker in the presence of potassium persulfate initiator. The synthesized polymer gels have been characterized by Fourier-transform infrared (FT-IR) spectroscopy. The swelling capacity and crosslink density of the synthesized polymer gels have been determined and it was found that some of the polymer samples behave like super-absorbent polymers. These polymeric-gels can be utilized in various applications viz. as a catalyst for dye removal, for anion removal from water and for heavy metal removal etc.

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Multicomponent Materials to Improve Solubility: Eutectics of Drug Aminoglutethimide

Crystals ◽

10.3390/cryst12010040 ◽

2021 ◽

Vol 12 (1) ◽

pp. 40

Author(s):

Basanta Saikia ◽

Andreas Seidel-Morgenstern ◽

Heike Lorenz

Keyword(s):

Melting Point ◽

Molar Ratio ◽

Experimental Characterization ◽

X Ray ◽

Eutectic Mixtures ◽

Ft Ir ◽

Aqueous Solubilities ◽

Ft Ir Spectroscopy

Here, we report the synthesis and experimental characterization of three drug-drug eutectic mixtures of drug aminoglutethimide (AMG) with caffeine (CAF), nicotinamide (NIC) and ethenzamide (ZMD). The eutectic mixtures i.e., AMG-CAF (1:0.4, molar ratio), AMG-NIC (1:1.9, molar ratio) and AMG-ZMD (1:1.4, molar ratio) demonstrate significant melting point depressions ranging from 99.2 to 127.2 °C compared to the melting point of the drug AMG (151 °C) and also show moderately higher aqueous solubilities than that of the AMG. The results presented include the determination of the binary melt phase diagrams and accompanying analytical characterization via X-ray powder diffraction, FT-IR spectroscopy and scanning electron microscopy.

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Extinction Coefficient Determination of Polymeric Materials and Their Use in the Optical Characterization of Infrared Microscopes: A Preliminary Investigation into Quantitative Infrared Microspectroscopy

Applied Spectroscopy ◽

10.1366/00037020260377689 ◽

2002 ◽

Vol 56 (11) ◽

pp. 1397-1402 ◽

Cited By ~ 3

Author(s):

Louis G. Tisinger ◽

André J. Sommer

Keyword(s):

Preliminary Investigation ◽

Polymeric Materials ◽

Infrared Microspectroscopy ◽

Poly Ethylene Terephthalate ◽

Ft Ir ◽

Poly Ethylene ◽

Sample Configuration ◽

Ft Ir Spectroscopy

A comparison of infrared spectra collected in both a macro sample configuration and on a microscope accessory was conducted. The results of this comparison demonstrated that as the microscope aperture was reduced, absorbance values increased for a given polymer film by as much as 33% as compared to the same data collected in the corresponding macro experiment. A detailed evaluation of the optical pathlength for both the micro and macro configurations was conducted. Results of this evaluation and that of detector non-linearity showed that the latter effect was most problematic. During the course of the investigation the average angle of light traversing through the objective was determined for several infrared microscopes. Further analysis indicated that changing the aperture size of the microscope can have significant influence on the absorbance values obtained. In addition, extinction coefficients of poly(methyl methacrylate), polystyrene, poly(vinyl acetate), polycarbonate, and poly(ethylene terephthalate) were determined using macro FT-IR spectroscopy.

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Multicomponent Materials to Improve Solubility: Eutectics of Drug Aminoglutethimide

10.20944/preprints202111.0571.v1 ◽

2021 ◽

Author(s):

Basanta Saikia ◽

Andreas Seidel-Morgenstern ◽

Heike Lorenz

Keyword(s):

Melting Point ◽

Experimental Characterization ◽

Analytical Characterization ◽

X Ray ◽

Eutectic Mixtures ◽

Ft Ir ◽

Aqueous Solubilities ◽

Ft Ir Spectroscopy

Here, we report the synthesis and experimental characterization of three drug-drug eutectic mixtures of drug aminoglutethimide (AMG) with caffeine (CAF), nicotinamide (NIC) and ethenzamide (ZMD). The eutectic mixtures (AMG-CAF, AMG-NIC and AMG-ZMD) demonstrate significant melting point depressions ranging from 99.2 to 127.2 °C compared to the melting point of the drug AMG (151°C) and also show significantly higher aqueous solubilities than that of the AMG. The results presented include the determination of the binary melt phase diagrams and accompanying analytical characterization via X-ray powder diffraction, FT-IR spectroscopy and Scanning electron microscopy.

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