used and demonstrate that thermogravimetry (TG) can be a good replacement for these methods.
Sampling and current analysis techniques
As CFR sect. 211.67 states, “Equipment and utensils shall be cleaned, maintained, and
Authors:A. J. D. Fernandes, J. H. P. Barbosa, O. G. Silva, M. G. Fonseca, L. H. N. Arakaki, and J. G. P. Espínola
characterization was done by X-ray diffractometry (XRD), infrared (IR) spectroscopy, thermogravimetry (TG) and nuclear magnetic resonance ( 29 Si NMR). The chemical stability was implemented for pH varying at 1.0–6.0.
Methods and materials
Authors:Ana Paula Barreto Gomes, Fátima Duarte Freire, and Cícero Flávio Soares Aragão
evaluate of the vapor pressure of the curves of warifteine and methylwarifteine using thermogravimetry analysis.
Methods and materials
Methylparaben (reference) was purchased from Dinalab (NF00222). Warifteine and
Authors:Ana Moreira, Bruno Souza, and Ana Teixeira
Naphthenates are produced when naphthenic acids present in crude oil are mixed with brine. They deposit at oil/water interface
and are insoluble in either of the phases causing a large problem to the oil industry. Generally, naphthenates precipitate
jointly with others compounds such as sulfates and carbonates. This fact makes difficult their characterization. In this study,
calcium stearate formation from stearic acid was investigated, under different conditions, as a previous model to understanding
of calcium naphthenate precipitation. Medium reactions distinct were studied and the results indicated that the ethanol medium
was the most efficient for the formation of solids because in this only case, the stearic acid was completely converted into
stearate. Monitoring of the conversion was performed by thermogravimetry in spite of this technique not be typical in salts
characterization. Nevertheless, the thermogravimetric analysis showed that is possible to identify differences between an
organic acid, a salt of this acid and an inorganic salt, in the same sample. Infrared spectra was used in order to confirm
the results obtained by thermogravimetry. However, this technique showed less efficiency and sensibility.
Authors:Mohammad R. Saraji-Bozorgzad, Thorsten Streibel, Erwin Kaisersberger, Thomas Denner, and Ralf Zimmermann
-skimmer technology was used for direct sampling of evolved gases from thermogravimetry (TG) in conjunction with a time-of-flight mass spectrometric detection (TOFMS) and a photo ionisation with VUV light (single photon ionisation, SPI). Furthermore an innovative VUV
Authors:F. M. Aquino, D. M. A. Melo, R. C. Santiago, M. A. F. Melo, A. E. Martinelli, J. C. O. Freitas, and L. C. B. Araújo
developed to determine some kinetic parameters. In these studies, the most-used thermal analysis techniques are thermogravimetric analysis (TG) and differential thermal analysis (DTA) [ 6 ]. Thermogravimetry is a technique in which the mass of a substance is
The objective of this research was to investigate the effect of different clay composition and concentrations on the thermal
behaviour and kinetics of heavy crude oil in limestone matrix by thermogravimetry (TG/DTG). In TG/DTG experiments, three distinct
reaction regions were identified in all of the crude oil + limestone mixture known as low temperature oxidation (LTO), fuel
deposition (FD) and high temperature oxidation (HTO) respectively. Addition of clay to porous matrix significantly affected
the reaction regions. Significant reduction of activation energy due to addition of clay to crude oil indicates the catalytic
effect of clay on crude oil combustion.
Authors:M. Saraji-Bozorgzad, R. Geißler, T. Streibel, M. Sklorz, E. Kaisersberger, T. Denner, and R. Zimmermann
The potential of hyphenating thermogravimetry (TG) and soft photo ionisation mass spectrometry (EBEL-SPI-MS) for fundamental
and applied research and material analysis has been demonstrated by a newly developed TG-SPI quadrupole MS coupling (TG-SPI-QMS).
Thermal decomposition of three common plastics, polyethylene (PE), polystyrene (PS) and polyvinylchloride (PVC) has been studied.
While the decomposition of PE and PS in inert atmosphere takes place in a one step process (main mass loss at about 490 and
420 °C, respectively), PVC decomposes in a two step mechanism. The organic signature of the PE decomposition shows homologous
series of alkenes and polyenes, while PS is forming mainly styrene mono- and oligomers. In the PVC decomposition, firstly
hydrogen chloride (HCl) is eliminated in a hydro-dechlorination reaction (1st mass loss step: 285–305 °C), this is accompanied
by the emission of the carbon skeletons of small aromatics (predominately benzene and naphthalene). In the second step (2nd
mass loss step: 490–510 °C), the residual cross-linked polyolefin moieties decompose under release of heavily alkylated aromatics,
including larger PAH. Chlorinated aromatics are formed only in trace levels.
using thermogravimetry (TG) of water desorption as main method for the mass analysis of intercalated compounds [ 18 – 20 ].
Layered oxides NaLnTiO 4 (Ln = Nd, La) and CsNdTa 2 O 7 were prepared by conventional