In Situ Fourier Transform Infrared Characterization of the Effect of Electrical Fields on the Flame Synthesis of TiO2Particles

1997 ◽  
Vol 9 (12) ◽  
pp. 2702-2708 ◽  
Author(s):  
Philip W. Morrison, ◽  
Ram Raghavan ◽  
Andrew J. Timpone ◽  
Christian P. Artelt ◽  
Sotiris E. Pratsinis
1988 ◽  
Vol 42 (6) ◽  
pp. 945-951 ◽  
Author(s):  
Meg Martin Thompson ◽  
Richard Alan Palmer

Fourier transform photoacoustic and diffuse reflectance spectroscopies (FT-IR-PAS and -DRS) have been used in situ to monitor the reaction of SO2 (1.5% in N2) with particulate CaCO3 at temperatures up to 400°C (PAS) and 690°C (DRS). The PA spectra indicate that at 360°C SO2 is physisorbed on the CaCO3 surface. This species is readily desorbed by N2 purging. Under continuous SO2/N2 exposure at 400°C and above, the physisorbed species is shown by the DR data to be converted first to oxygen-bound and then to nonspecifically bound pyramidal SO3−. Reaction of the SO3= with SO2 to form SO4− begins at 400°C and is essentially complete at 690°C. The DR data further indicate that for the SO4−: (1) at temperatures between 400 and 640°C a monodentate C3 v species forms; (2) above 640°C the SO4− ion has nearly Td symmetry; and (3) upon subsequent cooling, the SO4− exhibits the characteristics of a chelating C2 v species.


Langmuir ◽  
1997 ◽  
Vol 13 (8) ◽  
pp. 2380-2389 ◽  
Author(s):  
V. Climent ◽  
A. Rodes ◽  
J. M. Orts ◽  
J. M. Feliu ◽  
J. M. Pérez ◽  
...  

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