The Application of Thermoanalytical Techniques to Reaction Kinetics: The Thermogravimetric Evaluation of the Kinetics of the Decomposition of Calcium Oxalate Monohydrate

Freeman, Eli S.; Carroll, Benjamin

doi:10.1021/j150562a003

Cited by 1,761 publications

(509 citation statements)

References 0 publications

Supporting

Mentioning

475

Contrasting

Unclassified

Order By: Relevance

“…In general, the versions of the MTA-TPD method, worked out by the author [302,303,332], make it possible to obtain the following: thermal desorption curves (or mass thermograms); the spectra of volatile components under the condition of linear heating of the sample (in the temperature range 25 -1000°C); the energy of activation of thermal desorption; and other kinetic parameters. The kinetic parameters have been estimated by known methods [341][342][343][344][345][346]. A characteristic feature of the MTA-TPD method is a high sensitivity due to the design of a pyrolysis chamber.…”

Section: Methodsmentioning

confidence: 99%

“…5) we resorted to graphic construction of the subtractive differential thermokinetic curves, which were then processed according to a known procedure [332,342,343]. The results, which are summarized in Table 2, show that the activation energy of desorption E D increases from 6 to 10 kcal mol − 1 (26-44 kJ mol − 1 ) as the extent of the silica surface covered with physically adsorbed water decreases to q H 2 O : 0.…”

Section: Boundary Temperature For Remo6ing Physically Adsorbed Water mentioning

confidence: 99%

See 1 more Smart Citation

The surface chemistry of amorphous silica. Zhuravlev model

Zhuravlev

2000

Colloids and Surfaces A: Physicochemical and Engineering Aspect

2,057

142

1,967

View full text Add to dashboard Cite

A review article is presented of the research results obtained by the author on the properties of amorphous silica surface. It has been shown that in any description of the surface silica the hydroxylation of the surface is of critical importance. An analysis was made of the processes of dehydration (the removal of physically adsorbed water), dehydroxylation (the removal of silanol groups from the silica surface), and rehydroxylation (the restoration of the hydroxyl covering). For each of these processes a probable mechanism is suggested. The results of experimental and theoretical studies permitted to construct the original model (Zhuravlev model-1 and model-2) for describing the surface chemistry of amorphous silica. The main advantage of this physico-chemical model lies in the possibility to determine the concentration and the distribution of different types of silanol and siloxane groups and to characterize the energetic heterogeneity of the silica surface as a function of the pretreatment temperature of SiO 2 samples. The model makes it possible to determine the kind of the chemisorption of water (rapid, weakly activated or slow, strongly activated) under the restoration of the hydroxyl covering and also to assess of OH groups inside the SiO 2 skeleton. The magnitude of the silanol number, that is, the number of OH groups per unit surface area, h OH , when the surface is hydroxylated to the maximum degree, is considered to be a physico-chemical constant. This constant has a numerical value: h OH,AVER =4.6 (least-squares method) and h OH,AVER = 4.9 OH nm − 2 (arithmetical mean) and is known in literature as the Kiselev-Zhuravlev constant. It has been established that adsorption and other surface properties per unit surface area of silica are identical (except for very fine pores). On the basis of data published in the literature, this model has been found to be useful in solving various applied and theoretical problems in the field of adsorption, catalysis, chromatography, chemical modification, etc. It has been shown that the Brunauer -EmmettTeller (BET) method is the correct method and gives the opportunity to measure the real physical magnitude of the specific surface area, S Kr (by using low temperature adsorption of krypton), for silicas and other oxide dispersed solids.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Boundary Temperature For Remo6ing Physically Adsorbed Water mentioning

confidence: 99%

The surface chemistry of amorphous silica. Zhuravlev model

Zhuravlev

2000

Colloids and Surfaces A: Physicochemical and Engineering Aspect

2,057

142

1,967

View full text Add to dashboard Cite

show abstract

“…The Freeman and Corroll procedure [42] was used to evaluate the kinetic parameters such as order of reaction and energy of activation from a single experimental curve from the plot of…”

Section: Kinetic Studymentioning

confidence: 99%

Synthesis, spectral characterization, in vitro microbial and cytotoxic studies of lanthanum(III) and thorium(IV) complexes with 1,2,4-triazole Schiff bases

Bagihalli

Patil

Badami³

2009

Journal of Enzyme Inhibition and Medicinal Chemistry

View full text Add to dashboard Cite

“…Um grande número de métodos foram desenvolvidos para derivar os parâmetros cinéticos k 0 , E a e n a partir de experiências dinâmicas de TGA baseadas na Equação (3.5). Geralmente, os métodos podem ser divididos em métodos integrais, tais como aqueles de Coats e Redfern (Coats e Redfern, 1964) e Ozawa (Osawa, 1965) e métodos diferenciais tais como os de Kissinger (Kissinger, 1956), Friedman (Friedman, 1965), Freeman e Carroll (Freeman e Carroll, 1958) e Borchardt e Daniels (Borchardt e Daniels, 1957), dependendo se a forma integral ou diferencial da Equação (3.5)é utilizada. Alguns métodos integrais e diferenciais, tais como Freeman e Carroll (Freeman e Carroll, 1958) e Borchardt e Daniels (Borchardt e Daniels, 1957) são baseados em um ensaio de taxa de aquecimentoúnico, que pode trazer erros nos parâmetros cinéticos de reações complexas.…”

Section: Modelo Isoconversionalunclassified

“…Geralmente, os métodos podem ser divididos em métodos integrais, tais como aqueles de Coats e Redfern (Coats e Redfern, 1964) e Ozawa (Osawa, 1965) e métodos diferenciais tais como os de Kissinger (Kissinger, 1956), Friedman (Friedman, 1965), Freeman e Carroll (Freeman e Carroll, 1958) e Borchardt e Daniels (Borchardt e Daniels, 1957), dependendo se a forma integral ou diferencial da Equação (3.5)é utilizada. Alguns métodos integrais e diferenciais, tais como Freeman e Carroll (Freeman e Carroll, 1958) e Borchardt e Daniels (Borchardt e Daniels, 1957) são baseados em um ensaio de taxa de aquecimentoúnico, que pode trazer erros nos parâmetros cinéticos de reações complexas. Friedman (Friedman, 1965), Osawa (Osawa, 1965) e métodos de Kissinger (Kissinger, 1956) usam taxas de multi-aquecimento que calcula os parâmetros cinéticos em várias conversões e, leva a uma média como os parâmetros da reação global.…”

Section: Modelo Isoconversionalunclassified

Gaseificação de microalgas: estudo termogravimétrico e modelagem matemática do processo em reator solar.

Figueira¹

View full text Add to dashboard Cite

The Application of Thermoanalytical Techniques to Reaction Kinetics: The Thermogravimetric Evaluation of the Kinetics of the Decomposition of Calcium Oxalate Monohydrate

Cited by 1,761 publications

References 0 publications

The surface chemistry of amorphous silica. Zhuravlev model

The surface chemistry of amorphous silica. Zhuravlev model

Synthesis, spectral characterization, in vitro microbial and cytotoxic studies of lanthanum(III) and thorium(IV) complexes with 1,2,4-triazole Schiff bases

Gaseificação de microalgas: estudo termogravimétrico e modelagem matemática do processo em reator solar.

Contact Info

Product

Resources

About