Steady state kinetic equation for SO2 oxidation on vanadium catalysts

Oxidation of sulfur dioxide over supported solid V2O5/SiO2 and supported molten salt V2O5?Cs2SO4/SiO2 catalysts: molecular structure and reactivity

“…4 shows representative in situ Raman spectra obtained for catalysts samples A9Cs, A5Cs, and C21Cs at 500 • C under flowing O 2 (spectra a, b, and c). One can observe that the spectra of all catalysts possess bands at 1068, 960, and 611 cm −1 , which are due to the well-known ν 3 (SO 4 2− ), ν 1 (SO 4 2− ), and ν 4 (SO 4 2− ) modes of crystalline Cs 2 SO 4 , respectively [13]. These bands dominate the spectra of sample A9Cs (Fig.…”

“…Furthermore, the 770/830 cm −1 strong and broad feature, which is very characteristic of the molten dimeric (VO) 2 O(SO 4 ) 4 4− [12,14], appears in spectrum (Fig. 6b).…”

“…One should expect to observe the group vibrations of VO 3+ and SO 4 2− units of the VO 2 (SO 4 ) 2 3− V V complex. The four sulfate fundamentals (ν 1 -ν 4 ) for a tetrahedral T d configuration span the representation…”

“…In order to facilitate the discussion, the spectrum of the V 2 O 5 -Cs 2 S 2 O 7 molten mixture with X 0 V 2 O 5 = 0.24 (i.e., merely a mixture of the (VO) 2 O(SO 4 ) 4 4− molten complex and S 2 O 7 2− ) at 450 • C is displayed in Fig. 6f.…”

“…The literature has abundant rate equations developed for the catalytic oxidation of SO 2 [3]. Worth mentioning is the renowned Boreskov rate equation implying a first-order dependence on O 2 partial pressure [4]. The catalyst is usually made by calcination of silica (diatomaceous earth), vanadium pentoxide (or other vanadium precursors), and alkali promoters (usually in the form of sulfates) with an alkali-to-vanadium atomic ratio between 2 and 5 [2,5].…”