Thermal Desorption
Mostrando 1-12 de 51 artigos, teses e dissertações.
-
1. Microwave radiation influence on the thermal and spectroscopic properties of Na-birnessite-type material
Resumo No presente trabalho, apresenta-se um estudo da influência da radiação micro-ondas nas propriedades térmica e espectroscópica, assim como estrutural (ordem-desordem) e morfológica, de óxido de Mn estruturado em camada tipo Na-birnessita. A rota empregada para obtenção da matriz lamelar foi a precipitação redox. Os produtos foram caracteriza
Cerâmica. Publicado em: 14/11/2019
-
2. Fabrication of Fish Gelatin Microfibrous Mats by Solution Blow Spinning
In this work microfiber mats of Nile tilapia (Oreochromis niloticus) gelatin were successfully fabricated by using Solution Blow Spinning technique. The concentration and viscosity of fish gelatin solution, in acid acetic/water (80% v/v), were correleted to the morphology and diameter of the gelatin microfibers. It was found that increased solution viscosity
Mat. Res.. Publicado em: 30/09/2019
-
3. Dispersive Solid Phase Extraction Headspace Sampling in Gas Chromatography-Mass Spectrometric Analysis of Volatiles: Application to Separation of Polycyclic Aromatic Hydrocarbons
For the first time, dispersive solid phase extraction combined with headspace sampling was introduced and applied to separation and pre-concentration of polycyclic aromatic hydrocarbons (PAHs) as representative of volatile and semi-volatile compounds, from aqueous solutions and sediments using multiwall carbon nanotubes (MWCNTs). After adsorption, PAHs were
J. Braz. Chem. Soc.. Publicado em: 2019-04
-
4. Effect of thermal treatment on the catalytic activity of a Fe-rich bentonite for the photo-Fenton reaction
Resumo O objetivo deste trabalho foi avaliar a degradação do corante rodamina B em solução aquosa por reação foto-Fenton sob irradiação visível utilizando uma bentonita rica em ferro como catalisador. O material foi tratado termicamente a baixa temperatura (200 ºC) e caracterizado por DRX, isotermas de adsorção-dessorção de N2, FTIR, MEV-EDS e
Cerâmica. Publicado em: 2019-01
-
5. Influence of Nanoxides on Diffusivity and Solubility of Hydrogen in Pd-based alloys
The hydrogen interaction in palladium alloys with addition of Ce, Zr and Y was studied. These alloys are produced by arc-melting and then cold rolled into thin foils. Heat treatment at 800ºC for 24h in air atmosphere is applied to induce internal oxidation. Hydrogen permeation tests and TDS (Thermal Desorption Spectroscopy) are carried out to evaluate hydro
Mat. Res.. Publicado em: 11/01/2018
-
6. Thermal Dehydrogenation Characteristics of Li-Sr-Al-N-H Hydrogen Storage System
Thermolysis behavior of the Li-Sr-Al-N-H hydrogen storage system prepared by ball milling of Sr2AlH7 + LiNH2 mixture was investigated in this paper. The results show that thermal decomposition of the Li-Sr-Al-N-H system proceeds mainly in two steps with only hydrogen desorption. The thermal stability of this system is lowered as compared to the individual st
Mat. Res.. Publicado em: 18/12/2017
-
7. Using Magnetized (Fe3O4 / Biochar Nanocomposites) and Activated Biochar as Adsorbents to Remove Two Neuro-Active Pesticides from Waters
This work describes the removal of pesticides from water using activated and magnetized biochars produced from exhausted husk, and dry tannin from barks of black wattle (Acacia mearnsii De Wild.). These materials were characterized using chemical, spectroscopic, thermal, solid structure and surface area techniques. The activated and magnetized biochars were
J. Braz. Chem. Soc.. Publicado em: 2017-10
-
8. Effect of PVA Concentration on Structure and Performance of Precipitated Iron-Based Catalyst for Fischer-Tropsch Synthesis
Fe2O3 catalysts were prepared by co-precipitation method with the assistance of polyvinyl alcohol (PVA) for Fischer-Tropsch synthesis. Effects of PVA concentration on structure and performance of the catalyst were investigated in a fixed reactor at 230-310 °C, 1.5 MPa, 2000 h-1, and syngas H2/CO = 2.0. The catalysts were characterized by N2 adsorption, scan
J. Braz. Chem. Soc.. Publicado em: 2017-08
-
9. SELECTIVE SYNTHESIS OF PEG-MONOESTER USING CESIUM HETEROPOLY ACID AS HETEROGENEOUS CATALYST
Esterification of oleic acid with polyethylene glycol 600 (PEG-600) to produce polyethylene glycol monooleate (PEG-monooleate) and polyethylene glycol dioleate (PEG-dioleate) as by-product has been studied in the presence of heterogeneous acid catalysts, i.e. cesium heteropoly acid (Cs HPA). The results are compared with those obtained from a classical homog
Quím. Nova. Publicado em: 2017-06
-
10. Catalytic Capture of CO2 with Template-Containing Zn/MCM-41 and Its Transformation to Solid Carbonate
Mesoporous MCM-41 materials modified by zinc have been prepared by non hydrothermal procedure. Zinc has been introduced by the direct synthesis (DS), template ion-exchange (TIE) and wet impregnation (WI) methods. The catalysts were characterized by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy-scanning electron microscopy (EDX-SEM), thermogra
J. Braz. Chem. Soc.. Publicado em: 2016-12
-
11. Gas-Phase Conversion of Glycerol to Acetol: Influence of Support Acidity on the Catalytic Stability and Copper Surface Properties on the Activity
Mesoporous mixed copper-aluminum oxides and copper-silicon oxides were synthesized with polymeric precursors route in order to evaluate the effect of the support acidity on the catalytic stability due to the carbon deposit and the copper surface characteristics on the catalytic activity for the gas-phase conversion of glycerol to acetol. The samples were cha
J. Braz. Chem. Soc.. Publicado em: 2016-12
-
12. EFEITO DO DIOXIDO DE CARBONO SOBRE A ESTABILIDADE DA FASE Ca2Fe2O5 APLICADA NO PROCESSO DE DEGRADAÇÃO FOTOCATALITICO DO AZUL DE METILENO
Solid samples containing a Ca2Fe2O5 phase were synthesized using the Pechini method. The samples were characterized using X-ray diffraction, thermogravimetric analysis, differential thermal analysis, X-ray fluorescence, nitrogen adsorption/desorption isotherms, and scanning electron microscopy. The stability of the Ca2Fe2O5 phase was evaluated in the photoca
Quím. Nova. Publicado em: 2015-12