TY - JOUR
T1 - Hydrothermal synthesis of cement phases
T2 - An in situ synchrotron, energy dispersive diffraction study of reaction kinetics and mechanisms
AU - Shaw, S.
AU - Henderson, C. M B
AU - Clark, S. M.
PY - 2001
Y1 - 2001
N2 - The equipment and methodology for in situ study of hydrothermal reactions using synchrotron radiation are described. This equipment is currently used at the Synchrotron Radiation Source, Daresbury Laboratory, UK, at temperatures up to about 230°C. To demonstrate the utility of this approach three experiments are described: crystallization of Fe- and Cr- doped tobermorite starting compositions to produce mixed tobermorite/xonotlite end products; crystallization of gyrolite and pectolite from a starting gel of gyrolite composition reacted with NaOH solution; and formation of the hydrogarnet, katoite, from a mixture of portlandite, amorphous alumina and amorphous silica. Kinetic analyses using the Avrami equation are reported for each system and used to calculate rate constants and deduce reaction mechanisms. Higher synchrotron X-ray energies (up to 200 keV) would allow thicker walled pressure vessels to be used, with a consequent increase in temperature to supercritical conditions, perhaps to above 400°C.
AB - The equipment and methodology for in situ study of hydrothermal reactions using synchrotron radiation are described. This equipment is currently used at the Synchrotron Radiation Source, Daresbury Laboratory, UK, at temperatures up to about 230°C. To demonstrate the utility of this approach three experiments are described: crystallization of Fe- and Cr- doped tobermorite starting compositions to produce mixed tobermorite/xonotlite end products; crystallization of gyrolite and pectolite from a starting gel of gyrolite composition reacted with NaOH solution; and formation of the hydrogarnet, katoite, from a mixture of portlandite, amorphous alumina and amorphous silica. Kinetic analyses using the Avrami equation are reported for each system and used to calculate rate constants and deduce reaction mechanisms. Higher synchrotron X-ray energies (up to 200 keV) would allow thicker walled pressure vessels to be used, with a consequent increase in temperature to supercritical conditions, perhaps to above 400°C.
UR - http://www.scopus.com/inward/record.url?scp=0345818676&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0345818676
SN - 0895-7959
VL - 20
SP - 311
EP - 324
JO - High Pressure Research
JF - High Pressure Research
IS - 1-6
ER -