Preparation and SO₂ capture performance of NCP10/LiOH carbon-based composite for deep desulfurization

Carbon materials mainly capture sulfur dioxide (SO₂) from gas through physical adsorption, therefore their SO₂ capture performance will decrease with the increase in desulfurization temperature. In order to meet the stringent requirements of deep desulfurization, further improvements on carbon materials are necessary, improving their SO₂ capture performance and adaptability to changes in desulfurization temperature. In this study, a carbon material (NCP10) was modified with various alkali metal compounds with the aim of enhancing the SO₂ capture performance and adaptability to temperature changes. The results showed that the NCP10/LiOH composite had the best average SO₂ removal rate (100%) and SO₂ capture capacity (113.6mgSO2/gmaterial) within the first hour of reacting at 60 °C, the SO₂ removal rate and SO₂ capture capacity of the NCP10/LiOH composite were 29% and 29% higher than those of the pure NCP10 material, respectively. While the SO₂ capture performance of the NCP10 modified with LiCl, Li₂CO₃, NaOH and KOH were not sufficient for deep desulfurization, the SO₂ capture performance of the NCP10/LiOH(2:1) composite was able to meet the requirements of deep desulfurization in the temperature range of 25–100 °C by the physical adsorption and chemical absorption synergistically effect.