Removal of CO₂ by CaO/MgO and CaO/Ca₉Al₆O₁₈ in the Presence of SO₂

Abstract

Sorbents with their components CaO/MgO and CaO/Ca 9 Al 6 O 18 were produced from calcium d -gluconate monohydrate, magnesium d -gluconate hydrate, and aluminum l -lactate hydrate as precursors with a simple wet mixing method. The effects of sorbents type, mass proportion, SO 2 concentration, and calcination temperature on sorbent capability were studied. The results show that CaO/MgO (75:25%, w/w) kept the best CO 2 -capture capability, while CaO/Ca 9 Al 6 O 18 (75:25%, w/w) kept the best cyclic stability. The CO 2 -capture process is drastically blocked when SO 2 exists. The CO 2 -capture capacity drops quickly when the SO 2 concentration is promoted. However, the cumulative SO 2 -capture capacity increases at the same time. The total calcium use rises tenderly after many cycles, and the tendency becomes more obvious with an increasing SO 2 concentration. The effect of the calcination temperature on CaO/MgO and CaO/Ca 9 Al 6 O 18 absorption characteristics shows little difference.