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endothermic reactions, which are dehydration below 447 K with mass loss of 0.13 wt% to 1.7 wt%, dehydroxylation at 525–609 K with mass loss of 1.09 wt%–4.49 wt% and decomposition of aluminosilicates... at various temperatures. The first endothermic reactions in all the cases were observed at a temperature below 447 K, it is due to dehydration of hygroscopic moisture (≤1.7 wt%), and followed by a second......
, extremely low concerntration of Fe and Mn contents. Based on these data, anhydrite cements can be thought to be related to the alkaline fluid overlying gypsum-salt layer produced by dehydration. The barite... are a little higher than the temperatures at which the dehydration of the gypsum-salt layer occurred, which is matched with the geothermal gradient evolution. The highly saline fluids rich in alkali metal......
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treatment, they lose some part of hydrate water depending upon applied temperature. This process is known as calcination or dehydration. One of the goals of dehydration process is to obtain a porous solid... increases [21-23]. But, the dehydration process on the leaching rate of ulexite becomes effective till a certain dehydration temperature. During the dehydration process, some changes in the crystal structure......
to glucose are 99 kJ/mol and 114 kJ/mol, respectively. MOREAU et al [37] revealed that the dehydration of fructose using water as solvent is not controlled by external diffusion according... and dehydration reactions. HMF was successfully prepared by a hydrothermal method from the waste cotton stalk with a maximum yield of 27.2%. This sustainable degradation process may promise a candidate......
, it can be concluded that the dehydration of water molecules was completed and decomposition of the anhydrous precursor was started before 150 °C which is consistent with DSC-TG thermoanalysis curves... processes over the temperature range from 25 to 270 °C which include dehydration and two overlapping endothermic decomposition processes (Fig. 2), showing peaks at 201 and 222 °C (β=5 °C/min......
, indicating that the dehydration reaction of CoC2O4·2H2O occurs (see Eq.(1)). At 296 °C, an exothermic peak exists on DTA curve, suggesting that CoC2O4 reacts with O2 in the air to form Co3O4 and releases... with the increase of heating rate. The CoC2O4·2H2O was heated in the flow of air (100 mL/min) with the heating rate of 10 °C/min, and the endothermic peak of dehydration reaction and the exothermic peak......
components[5]. Furthermore, nano-zirconia has interesting catalytic actions for isomerization of olefins [6] and epoxides[7], dehydration of alcohols[8-9], and so on[10-11]. Practical synthesis methods... in gas phase bull [J]. Chem Soc Jpn, 1976, 49: 563-564. [8] YAMAGUCHI T, SASAKI H, TANABE K. High selectivities of zirconium oxide catalyst for isomerization of 1-butene and dehydration of sec......
] researched dehydration reaction kinetic of gibbsite with Kissinger equation. MACKENZIE et al [10] summarized the thermal decomposition of mechanically activated gibbsite. AMIRPIRAN et al [11] studied.... As the characteristic of thermal decomposition of high iron gibbsite ore is the dehydration of goethite (FeOOH), gibbsite (Al(OH)3) and diaspore (AlOOH), it is possible that the thermal decomposition kinetics of high......
corresponds to the dehydration peak of pure NiC2O4·2H2O and the mass loss in the TGA curve is 19.15%. The second peak of DTA curve occurs about at 360 °C, which corresponds to the decomposition peak of pure NiC2O4 and the mass loss in the corresponding TGA curve is 53.10%. The temperature ranges of dehydration and decomposition and the total mass loss of the precursor synthesized at pH=6.0 are accordant......
