Hydrotalcite
Mostrando 1-12 de 32 artigos, teses e dissertações.
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1. Synthesis of Hydrotalcite-Supported CdTe Semiconductor Nanocrystals for Electrochemical Detection of Ciprofloxacin
In this work, CdTe quantum dots (QDs) were controllably grown onto the surface of layered double hydroxide (LDH) aiming to develop a sensitive and selective method for the electrochemical detection of ciprofloxacin (CPX). Emission and absorption spectroscopy results as well as high-resolution transmission electron microscopy (HRTEM) images evidenced the form
J. Braz. Chem. Soc.. Publicado em: 23/05/2019
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2. Lithium containing MgAl mixed oxides obtained from sol-gel hydrotalcite for transesterification
Abstract The innumerous advantages of heterogeneous catalysts employed in biodiesel production have stimulated the search for a solid catalyst capable of replacing the industrially used homogeneous catalysts. This paper investigates the effect of the sol-gel method in the catalytic activity and stability of Li-MgAl mixed oxides prepared by the “in situ”
Braz. J. Chem. Eng.. Publicado em: 2018-01
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3. Epoxidized natural rubber and hydrotalcite compounds: rheological and thermal characterization
Abstract Epoxidized natural rubber (ENR) and synthetic non-modified hydrotalcite (HT) compounds were prepared and evaluated. Natural rubber (NR) was epoxidized with 20.6% of epoxy groups from a chemical modification of the latex. A sulfur-based curing system formulation with accelerators was used. The amounts of HT in the ENR-HT compositions was varied betwe
Polímeros. Publicado em: 21/09/2017
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4. ÓXIDOS METÁLICOS DERIVADOS DE MATERIAIS TIPO HIDROTALCITAS CONTENDO Ga3+ COMO CATALISADORES PARA SÍNTESE DE BIODIESEL ETÍLICO
Summary: The synthesis of like-hydrotalcites materials (layered double hydroxides - LDHs) with molecular formula MgxM3+y(CO3)(OH)16·4H2O in different ratios Mg2+/M3+ where M3+ is Al3+, Ga3+ or both was carried out by the coprecipitation method to be applied in the transesterification reactions for synthesis of ethyl biodiesel from soybean oil and ethanol. T
Quím. Nova. Publicado em: 2017-06
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5. New Multicomponent Reaction for the Direct Synthesis of β-Aryl-γ-nitroesters Promoted by Hydrotalcite-Derived Mixed Oxides as Heterogeneous Catalyst
A new approach based on multicomponent/domino combined reactions for the synthesis of γ-nitroesters promoted by a mixed aluminium-magnesium oxides derived from hydrotalcite-like material was developed. Different γ-nitroesters were synthesized in 15-95% yield using Meldrum's acid, aromatic aldehydes, nitromethane and different alcohols as reagents and solve
J. Braz. Chem. Soc.. Publicado em: 2017-02
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6. MOLECULAR VALIDATED MODEL FOR ADSORPTION OF PROTONATED DYE ON LDH
Abstract Hydrotalcite-like compounds are anionic clays of scientific and technological interest for their use as ion exchange materials, catalysts and modified electrodes. Surface phenomenon are important for all these applications. Although conventional analytical methods have enabled progress in understanding the behavior of anionic clays in solution, an e
Braz. J. Chem. Eng.. Publicado em: 2016-03
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7. Effect of Processing on Microstructure and Corrosion Mitigating Properties of Hydrotalcite Coatings on AA 6061 Alloy
Pitting corrosion of the aluminium cladding of spent nuclear fuels stored in light water pools has been observed. To prevent this, coating of the Al cladding with hydrotalcite (HTC) was proposed. This paper presents the effect of chemical bath and processing parameters on microstructure and corrosion behavior of HTC coatings on alloy AA 6061 specimens. The H
Mat. Res.. Publicado em: 03/11/2015
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8. Bacterial cellulose as a template for preparation of hydrotalcite-like compounds
Celulose bacteriana (BC) foi utilizada nesse estudo como molde na preparação de compostos do tipo hidrotalcita ou hidróxidos duplos lamelares (LDHs) pelo método da co-precipitação e submetida a três tempos de envelhecimento distintos. Os compósitos isolados contendo LDH suportado na BC (BC-LDH) foram calcinados para remoção da matriz orgânica. Os
J. Braz. Chem. Soc.. Publicado em: 2014-09
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9. Synthesis of Co-Al-Cl LDH by cathodic material reprocessing from cellular phone batteries
The aim of this paper was the recovering of the cathodic material from discarded lithium ion batteries for obtainment of the lamellar double hydroxides (LDHs) by the co-precipitation method at variable pH in HCl and H2O2 1:1 (v/v) acid solution containing Co and Al (extracted from cathodic material composed of LiCoO2 and aluminum foil). These metals were pre
Mat. Res.. Publicado em: 29/04/2014
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10. Remoção de cromo (VI) de soluções aquosas utilizando o compósito magnético calcinado hidrotalcita-óxido de ferro: estudo cinético e de equilíbrio termodinâmico
In this work, hydrotalcite, a layered double hydroxide, had its ion exchange properties combined with the magnetic properties of iron oxide to produce a magnetic adsorbent, HT-Fe 500. These magnetic composites can be used as adsorbents for anionic contaminants in water and subsequently removed from the medium by a simple magnetic process. Removal of chromium
Quím. Nova. Publicado em: 2013
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11. Comparação estrutural entre amostras de materiais tipo hidrotalcita obtidas a partir de diferentes rotas de síntese
Three samples of hydrotalcite-like materials (HTC) were synthesized and their structural characteristics were compared with two HTCs obtained commercially. Thermal analyses, FT-IR, PXRD and textural analyses were used to investigate the structural differences between commercial and synthetic samples. Particularly, the memory effect was observed at temperatur
Química Nova. Publicado em: 2012
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12. Hidróxidos duplos lamelares à base de escória de alto forno
Hydrotalcite like compounds (HT) were prepared by co-precipitation (Mg/Al = 3.5), using an acid solution with blast furnace slag and MgCl2.6H2O and aqueous solutions of NaOH. The following synthesis variables were investigated: temperature (30 and 45 ºC) and pH (9 and 12). Depending of the temperature two systems were observed: Mg-Al-CO3 (T = 30 ºC); Mg-Al
Química Nova. Publicado em: 2012