K. Kalucki et al., STUDIES ON PHYSICOCHEMICAL CHANGES OF VAN ADIUM CATALYST FOR OXIDATION OF SULFUR-DIOXIDE PROCEEDING DURING PROCESS IN INDUSTRIAL REACTOR, Przemysl Chemiczny, 72(10), 1993, pp. 400-403
There were tested changes of chemical and phase compositions of vanadi
um catylst EASE during work on plates of catalytic reactor intended fo
r oxidation of sulfur dioxide. As a result of catalyst work contents o
f promoters (potassium, vanadium, iron) decrease and calcium displaces
from plates of high temperature and settles on plates of lower temper
ature. The increase of temperature increases the rate of phase transit
ion of catalyst carrier from alpha-SiO2 (quartz) being the main compon
ent of carrier to other form of SiO2. In the fresh catalyst promoters
exist in two crystallographic phases: K3V(SO4) and KV(SO4)(2). Relativ
e fraction of low potassium content phase increases as temperature on
the plate decreases. Amorphous compound of potassium oxides with silic
on dioxide is supposed to form. The main changes in promotor phase pro
ceed during the first year of work; phase transitions proceed at the s
table rate.