Zsm 5
Mostrando 13-24 de 80 artigos, teses e dissertações.
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13. Preparation of Mesoporous Fe2O3-Supported ZSM-5 Zeolites by Carbon-Templating and their Evaluation as Photo-Fenton Catalysts to Degrade Organic Pollutant
Mesoporous Fe2O3-supported ZSM-5 zeolites were prepared by carbon-templating and subsequently evaluated as photo-Fenton catalysts to degrade a dye used as a model heavy organic pollutant. The synthesis procedure of the mesoporous ZSM-5 zeolites was performed employing a nucleating gel and carbon particles as mesopores template. Thereafter, the precursor salt
Mat. Res.. Publicado em: 20/10/2016
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14. Preparação do sistema Fe2O3/ZSM-5 para uso como catalisador na reação foto-Fenton
Resumo Este trabalho objetivou a preparação da zeólita ZSM-5 suportada com nanopartículas de óxido de ferro para uso como catalisador na degradação de um poluente orgânico em solução aquosa a partir do processo foto-Fenton. A zeólita foi preparada usando gel nucleante como indutor de formação da estrutura tipo MFI. Nanopartículas de óxido de f
Cerâmica. Publicado em: 2016-09
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15. Synthesis of CL-20 from TADB in a One-Pot Method by Zeolite/HNO3 as a New Nitrolysis System
Hexanitrohexaazaisowurtzitane (CL-20) is the most powerful non-nuclear explosive in the world. Herein, a greener and safer new one-pot method for the synthesis of CL-20 from tetraacetyldibenzylhexaazaisowurtzitane (TADB) has been developed through zeolite/98% HNO3. The H-ZSM-5 catalyst, with both Brønsted and Lewis acid sites, indicated higher catalytic act
J. Braz. Chem. Soc.. Publicado em: 2016-06
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16. USE OF A LOW-COST TEMPLATE-FREE ZSM-5 FOR ATMOSPHERIC PETROLEUM RESIDUE PYROLYSIS
To understand the physicochemical properties and catalytic activity during the pyrolysis of atmospheric petroleum residue, a template-free ZSM-5 zeolite was synthesized using a direct method without additional seeds or an organic structure director and compared with conventionally synthesized ZSM-5. The crystallinities of the two zeolites were evaluated by X
Quím. Nova. Publicado em: 2016-04
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17. Oxidative desulfurization of thiophene on TiO2/ZSM-12 zeolite
In this work the hydrothermal synthesis of ZSM-12 zeolite was performed, varying the MTEACl/SiO2 ratio, where the synthesis temperature was 140 ºC and the crystallization time was 144 hours. The catalysts were characterized by XRD, FTIR and TG. TiO2/ZSM-12 catalysts were used with titanium ions concentrations of 5, 10 and 15%. The oxidative desulfurization
Mat. Res.. Publicado em: 05/02/2016
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18. Polymerization of Ethylene with Zirconocene Heterogenized on Spherical ZSM-5
Homogeneous polymerization catalysts require large amounts of solvent and cannot control the polymer morphology. In order to solve this issue, a narrow-shaped spherical ZSM-5 zeolite was used in ethylene polymerization as a support for zirconocene (Cp2ZrCl2). Several heterogeneous catalytic precursors were prepared and used in ethyle
J. Braz. Chem. Soc.. Publicado em: 2015-07
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19. TUNGSTOPHOSPHORIC ACID HETEROGENIZED ONTO NH4ZSM5 AS AN EFFICIENT AND RECYCLABLE CATALYST FOR THE PHOTOCATALYTIC DEGRADATION OF DYES
Materials based on tungstophosphoric acid (TPA) immobilized on NH4ZSM5 zeolite were prepared by wet impregnation of the zeolite matrix with TPA aqueous solutions. Their concentration was varied in order to obtain TPA contents of 5%, 10%, 20%, and 30% w/w in the solid. The materials were characterized by N2 adsorption-desorption isotherms, XRD, FT-IR, 31P MAS
Quím. Nova. Publicado em: 2015-05
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20. Análise quantitativa das zeólitas ferrierita, ZSM-5 e mordenita presentes em amostras sintetizadas
Nos estudos de obtenção de materiais zeolíticos é comum a formação de misturas de fases cristalinas devido à estabilidade relativa destes materiais no meio reacional empregado na síntese. Desta forma, é extremamente importante quantificar as diversas fases presentes no sistema para otimizar os métodos de sínteses de uma determinada zeólita sem a
Cerâmica. Publicado em: 2015-03
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21. Synthesis of SAPO-34/ZSM-5 Composite and Its Catalytic Performance in the Conversion of Methanol to Hydrocarbons
SAPO-34/ZSM-5 composite was synthesized with nano-sized ZSM-5 zeolite as seeds and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen sorption, Fourier transform infrared (FTIR) and temperature-programmed desorption of ammonia (NH3-TPD); its catalytic performance in the conversion of methanol to hydrocarbons (MTH) w
J. Braz. Chem. Soc.. Publicado em: 2015-02
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22. Adsorção de CO2 em peneiras moleculares micro e mesoporosas
Microporous molecular sieves of type Y, Beta, ZSM-5, ZSM-12 and ZSM-35, and mesoporous molecular sieves of type MCM-41 and MCM-48, and these sieves modified with triethanolamine and ethylenediamine were obtained and characterized by XRD, FTIR, TGA and nitrogen adsorption. The adsorption tests were performed by the gravimetric method under a stream of CO2 at
Quím. Nova. Publicado em: 2014
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23. Preparação e caracterização de compósitos poliméricos baseados em amido termoplástico e materiais de alta área superficial: zeólita ZSM-5 e sílica coloidal
Foram produzidas amostras de amido termoplástico (TPS) reforçadas com materiais de alta área superficial, com o intuito de verificar a variação nas propriedades do polímero, com especial enfoque na sua permeabilidade a vapor d'água. Foram utilizadas como carga a sílica coloidal (área superficial de 122,7 m²/g) e uma zeólita do tipo ZSM-5, produzid
Polímeros. Publicado em: 19/04/2013
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24. FTIR study of the relation, between extra-framework aluminum species and the adsorbed molecular water, and its effect on the acidity in ZSM-5 steamed zeolite
The infrared spectroscopy study of zeolite samples, obtained by steam treatment at 560‑960 °C of the ZSM‑5 catalyst (framework Si/Al ratio of 13), suggests an association between adsorbed molecular water and extra‑framework aluminum hydroxyls generated after treatment. Moreover, infrared spectroscopy of adsorbed pyridine shows the reduction of the den
Mat. Res.. Publicado em: 26/03/2013