Cyclic adsorption characteristic of CaO/MgO and CaO/Ca₉Al₆O₁₈ for simultaneous CO₂/SO₂ capture

Four sorbents were prepared with CaO/MgO or CaO/Ca₉Al₆O₁₈ that was produced from precursors of calcium D-gluconate monohydrate, magnesium D-gluconate hydrate and aluminum L-lactate hydrate with a simple wet mixing method. The effects of sorbent type, mass proportioning, SO₂ concentration and calcination temperature on the adsorption capability of sorbent were studied. The results show that CaO/MgO( weight ratio 75%/25%)keeps the best CO₂ capture capability, while CaO/CaO/Ca₉Al₆O₁₈(weight ratio 75%/25%)keeps the best cyclic stability. The CO₂ capture process is drastically affected by SO₂. The CO₂ capture capacity drops quickly when the SO₂ concentration increases. However, the cumulative SO₂ capture capacity increases at the same time. The total calcium utilization rises tenderly after many cycles, which becomes more obvious with increasing the SO₂ concentration. The effect of calcination temperature on the adsorption characteristic of CaO/MgO and CaO/CaO/Ca₉Al₆O₁₈ differs little.