The rate equation for SO2 autoxidation in aqueous MnSo4 solutions containing H2SO4

Transition Metals in Atmospheric Liquid Phases. Sources, Reactivity, and Sensitive Parameters

“…On the basis of their experimental observations [induction period, manganese(II) and (III) dependence, sulfur dependence, oxygen dependence, pH dependence, etc.] and correlated with previous studies, 179,[257][258][259][260][261][262][263][264][265] Berglund et al 130 proposed a chemical mechanism at pH 2.4 for the manganesecatalyzed autoxidation of hydrogen sulfite (see Figure 13).…”

The influence of temperature and the concentration of MNSO4 on the simultaneous absorption and reaction of mixtures of SO2 and O2

“…The fast reaction regime was concluded by confirming that neither the volume nor the stirring rate of the liquid phase had any influence on the process. We are also satisfied that it is possible to accept the reaction orders of 0 for SO2 and 1 for O2 as reported in the literature (Alper and Abu-Sharkh, 1988;Pasiuk-Bronikowska and Bronikowski, 1981 ;Pasiuk-Bronikowska and Ziajka, 1985;Ulrich et al, 1986).…”

“…Although the oxidation reaction of sulphite catalyzed by transition metal ions has been well studied with the object of using it as a reaction to determine the characteristics of the mass transfer in gas-liquid contactors (Linek and Vacek, 1981), the experimental results have often contradicted each other, showing the complexity of the process involved. Thus, in some studies (Altwicker, 1979;Linek and Vacek, 1981;Pasiuk-Bronikowska and Bronikowski, 1981) the existence of an intermediary S2@= is not postulated, whereas Littlejohn (1988) has in fact detected its presence.…”

“…he study of the absorption and oxidation of SO2 in an T aqueous phase has a double interest. On the one hand it gives us information about reactions that take place in the atmosphere and also in films of water on metal surfaces (Altwicker, 1979;Pasiuk-Bronikowska and Bronikowski, 1981). Further to this, it shows us about the desulphurization of gases, where it is an unwanted reaction in regenerative wet processes and is the basis of those processes in which the absorbent capacity of the liquid phase increases significantly, leading to the possibility of making use of the sulphuric acid or other sulphates thus obtained (Huss et al, 1982;Pasiuk-Bronikowska and Ziajka, 1989).…”

Calcium Bisulfite Oxidation in the Flue Gas Desulfurization Process Catalyzed by Iron and Manganese Ions

“…Calcium bisulfite oxidation is considered to be an important issue in limestone/gypsum processes because forced oxidation in the scrubber loop improves the dewatering properties of the sludge, leading to the formation of gypsum (CaSO 4 ‚2H 2 O), a byproduct with a low adverse impact on the environment in comparison with the solid mixture of CaSO 3 ‚ 1 / 2 H 2 O and CaSO 4 usually produced. 1 The calcium bisulfite oxidation reaction has been extensively studied, both in the absence 2,3 and in the presence 4,5 of catalysts; a number of researchers devoted their studies to comprehension of the oxidation reaction path, 4,6 in particular when the occurrence of a chemical reaction is accompanied by the diffusion of oxygen in the liquid phase, which causes complex interactions that are rather difficult to enlighten. 7 This circumstance is encountered when the oxidation reaction takes place in the so-called heterogeneous conditions, achieved by contacting a sulfurous solution with an oxygen-containing gas phase, that is, the operating condition in FGD processes.…”