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Introduction Natural zeolites are the framework aluminosilicates with rather large amount of water molecules inside cavities and channels, up to 20% by weight [ 1 – 3 ]. Thermal dehydration of zeolites is usually accompanied

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Introduction The dehydration of Portland cement paste plays an important role in the concrete structure explosive spalling at fire. Calcium silicate hydrate (CSH) and calcium hydroxide (CH) are the main hydration phases which

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nesosilicate is observed when dehydrated hydration products contact with water [ 9 – 12 ]. With such a possibility, surface cementitious properties of coarse fly ash were improved by dehydration and rehydration processes, meanwhile the un-burnt carbon is

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decomposes approximately between 450 and 550 °C, calcium carbonate approximately between 700 and 900 °C, while the crystallisation water of the hydration products disappears gradually between 100 and 1,000 °C. It is considered that the total dehydration of

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dehydration/desolvation, hydration/solvation or polymorphic transformation of API in the manufacturing process, leading to the changes in solid-state physicochemical properties and bioavailability of APIs [ 3 – 7 ]. Thus, an analytical study for the

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Abstract  

A model developed for the estimation of the diffusion coefficient based on Fickian diffusion is applied to the dehydration of a Coober Pedy white play of colour (precious) opal using thermogravimetric analysis (TG). The model was originally applied to bulk and powdered opal (opal with no bulk). In this paper the opal was graded prior to TG analysis. The diffusion coefficient was calculated and is reported up to the critical point of water.

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Saet Byul Kim, Mi Ran Lee, Eun Duck Park, Sang Min Lee, HyoKyu Lee, Ki Hyun Park, and Myung-June Park

aid of acid catalysts, can be further converted into furfural by dehydration. The dehydration reaction has several side reactions such as isomerization, condensation and polymerization [ 2 ]. Furfural is widely used as an intermediate for the

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Thermal dehydrations

Calcium copper acetate hexahydrate and calcium cadmium acetate hexahydrate

Journal of Thermal Analysis and Calorimetry
Authors: Y. Masuda, K. Minagawa, W. Morita, Z. Zhong, and P. K. Gallagher

Abstract

The behaviour of thermal dehydrations of isomorphous complexes of calcium copper acetate hexahydrate, CaCu(CH3CO2)4·6H2O and calcium cadmium acetate hexahydrate, CaCd(CH3CO2)4· 6H2O was studied by means of thermal analyses and X-ray structural analysis. The enthalpy changes for the dehydration of CaCu(CH3CO2)4·6H2O and CaCd(CH3CO2)4·6H2O were 315±9.7 and 295±8.0 kJ mol−1, respectively. The DSC curves of the dehydrations indicated that the seemingly simple dehydrations are more complex than they appear at first sight. Apparent activation energies for the dehydrations of CaCu(CH3CO2)4·6H2O and CaCd(CH3CO2)4·6H2O were 85.7±7.4 and 87.9±12.5 kJ mol−1, respectively.

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Journal of Thermal Analysis and Calorimetry
Authors: Marcelo Kobelnik, Douglas Lopes Cassimiro, Adélia Emilia de Almeida, Clóvis Augusto Ribeiro, and Marisa Spirandeli Crespi

For the aluminum compound, the first mass loss occurred only between 30 and 110 °C (TG) due to dehydration, with a loss of 1.76%, corresponding to the endothermic peak (91 °C) in the DSC curve. After dehydration, between 191 and 638 °C, the thermal

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Preparation of the Ca–diclofenac complex in solid state

Study of the thermal behavior of the dehydration, transition phase and decomposition

Journal of Thermal Analysis and Calorimetry
Authors: Marcelo Kobelnik, Douglas Lopes Cassimiro, Clóvis Augusto Ribeiro, Diógenes dos Santos Dias, and Marisa Spirandeli Crespi

stages of dehydration, transition phase, and the first and second stages of thermal decomposition. Besides this, an investigation with two mass samples was carried out, in order to determine the effect of changing the experimental variables as well as the

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