The C 3 A was mechanically mixed with reagent grade gypsum, CaSO 4 ·2H 2 O, in the ratio 0.02 mol to 0.06 mol. The powder was slurried into 1 L of distilled decarbonated water …
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Gypsum wallboard has been used for over 100 years as a barrier to the spread of fire in residential and commercial structures. The gypsum molecule, CaSO 4 ·2H 2 O, provides …
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Figure 1 shows the TG and DTG curves of a high-purity gypsum sample. As thermal decomposition is occurring in an open pan, the steps represented by Eqs. 2 and 3 occur …
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The current strategy for developing fire-resistant gypsum boards is mainly based on adding porous materials. However, these additives are generally weaker in strength due to higher porosity and ...
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A stop shall be applied at one end of the curve to restrain one end or edge of the gypsum board during installation. Pressure shall be applied to the unrestrained end or edge of the gypsum …
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120, 180-200°C = Gypsum decomposition and water release (endotherm) 100-200ºC = Hydrate water from decomposition of calcium silicate hydrate (CSH) ... hence did not show noticeable …
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transition from hemihydrate gypsum to crystalline gypsum (dihydrate gypsum). This brief presents examples of TG/DTA and DSC measurements of the thermal changes of gypsum.
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percent gypsum in stucco. This curve is prepared by characterizing (using the pinhole pan procedure) a series of reference materials prepared to cover the anticipated range of the test …
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Figure 2 shows an overlay of gypsum DSC curves obtained with open crucibles in STA at atmospheric pres- sure and in DSC at 1, 16, 34, 50, and 67 bar. ... The weight loss owing to …
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The thermal decomposition curves obtained from the Hg reference samples, including HgCl 2, Hg 2 Cl 2, HgS, HgO, HgSO 4, and Hg 2 SO 4, are shown in Fig. 2. ... For …
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In this work, we have reinvestigated the thermal degradation kinetics of synthetic gypsum (CaSO4·2H2O) using a novel approach based on peak deconvolution followed by the …
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The Hg release curves (Hg t) generated by thermal decomposition of the seven FGD gypsum samples are shown in Fig. 4. By integrating the peak area of each Hg release …
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The DSC curve of gypsum powder showed an endothermic peak at the temperature 180 °C, which corresponded to the dehydration of bassanite to anhydrite. ... The …
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The DSC curve for the dehydration of calcium sulphate dihydrate shows a double peak which was not present in the DSC curve for the dehydration of natural gypsum. The mean weight loss for calcium sulphate dihydrate was …
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Fig. 6 TG and DTG curves for the decomposition of the dihydrate using 100 mL sealed aluminium pan: a – 20°C min–1 ; b – 10°C min–1 heating rate (sample mass: 25 mg) Table 3 Regression parameters from Kissinger equation for …
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2015. The feasibility of incorporation of recycled gypsum derived from post-consumer (construction and demolition) gypsum-based waste into the plasterboard manufacturing …
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Fig. 1. Example of TGA mass and mass loss rate curves (Type C gypsum board heated at 20 °C/min). ARRHENIUS-RATE THERMAL DECOMPOSITION KINETICS . Consider an …
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3.1 Thermo Composition Process of Gypsum. TG and DTA curves of AG, DG and WG gypsum are shown in Fig. 1.The thermal decomposition process of AG can be separated …
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Additionally, a comparison of the mercury present in WFGD gypsum from five different coal-fired power plants using thermal decomposition techniques showed that the …
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This explains the decomposition of gypsum at different forms of calcium sulphate dihydrate (CaSO 4 ·2H 2 O) to calcium sulphate anhydrite (CaSO 4 ) between 85 to 400 • C …
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Studies suggest that the peak in the specific curve around 700-800 °C corresponds to the decomposition of the calcium carbonate and magnesium carbonate content of the gypsum boards, and...
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For this study natural gypsum having the following composition was used. The gypsum was crushed and then sep- arated by Tyler standard sieves into narrow-size fractions. The -7f8 …
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Figure 5 and Figure 6 show the thermogravimetric curves of the cement mixture pastes after 3, 7, ... After 28 days of curing, characteristic peaks of gypsum decomposition …
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DTA curve shows two close endothermic peaks in the temperature range 120–200 °C as an indication of gypsum dehydration (Engbrecht and Hirschfeld, 2016) as well as a …
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Two–step process in the dehydration of gypsum Supplementary Figure S1 (Fig. S1–S4 are available on-line from https://doi/10.2465/jmps.220811) shows the TG and DTA curves of …
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decomposition of gypsum under different reducing atmo-sphere was carried out in the PTGA, Thermax 500. The gypsum used in the experiment is phosphogypsum, which ... Fig. 2 …
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Figure 1 shows the TG/DSC and thermal expansion curves of the gypsum between 20 and 800 C. The TG/DSC curves reveal that the bound water in CaSO 4 ·2H 2 O was totally removed …
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Decomposition curve for a mixture of calcium and magnesium oxalate dihydrate. There is a significant loss which occurs before 210°C- due to loss of water from the sample. ... So, if there is conversion of gypsum to …
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The relationship between separation time and the Hg compounds in gypsum. The thermal decomposition curves of Hg compounds in the FGD gypsum are shown in Fig. 8. After …
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The measurement shows that the carbon and organic content of the "bad" samples (green and blue curves) is almost identical with the reference samples (red and black curve). The weight …
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