Absorption of sulfur dioxide by molten carbonates

Abstract

curves and MPD schedules discussed in Cases 1 and 2 used 0.75 for the stability parameters. If in actuality they are really 0.8, then all of the SO2 concentration curves are too high and the MPD schedules somewhat in error.

Reactive collisions of sulfur dioxide with molten carbonates

“…This average is slightly higher than p react ¼ 0.68 AE 0.04 at 683 K reported above; the data were recorded by using different samples, which might account for the difference. McIlroy et al also did not observe changes in SO 2 uptake into the eutectic mixture from the melting point to 920 K, but they attributed this insensitivity to gas-phase diffusion limitations in their high-pressure reactor (12). The data in Fig.…”

“…From a practical viewpoint, the insensitivity to temperature may be advantageous because it implies that efficient SO 2 removal is not confined to temperatures near the eutectic point, where product SO 2− 3 ions (or SO 2− 4 ions upon oxidation) may be less soluble or cause solidification of the melt upon extended exposure (12). This insensitivity, when combined with the nearinterfacial conversion of SO 2 → CO 2 , suggests that thin flowing films or coatings of molten carbonates over a wide temperature range may efficiently remove SO 2 from waste gases.…”

“…Oldenkamp and Margolin developed an alternative method to remove SO 2 from flue gases by employing a molten eutectic mixture of Li 2 CO 3 , Na 2 CO 3 , and K 2 CO 3 (11). This liquid-phase reagent potentially avoids the wide variations in conditions observed for solid limestone and is regenerable (11,12). When bubbling SO 2 through the carbonate melt at 800 K, nearly 100% of the SO 2 is removed for contact times as short as 0.05 s (12).…”

“…This liquid-phase reagent potentially avoids the wide variations in conditions observed for solid limestone and is regenerable (11,12). When bubbling SO 2 through the carbonate melt at 800 K, nearly 100% of the SO 2 is removed for contact times as short as 0.05 s (12). In practice, this efficiency can be orders of magnitude higher than for solid CaCO 3 at the same reaction time.…”

Natural gas regeneration of carbonate melts following SO2 capture from non-ferrous smelter emissions

“…[6][7][8] However, despite its ability to scrub SO 2 from sulfur-poor ue gases (<2 vol% SO 2 ) down to 0.003 vol%, 6 it was deemed impractical for industrial use due to the complexity of the carbonate melt regeneration process. In its original version, the regeneration was multi-stage and required heating to 1173 K, a temperature at which the carbonate melt is too corrosive to contain without damage to reaction crucible.…”