Enhancing SO2 capture capacity by preparation of a nano-CaO sorbent with modified structural parameters

The reaction of CaO with SO₂ is one of the most important methods for flue gas desulphurisation. Two methods for producing high-capacity sorbents are investigated: a nanoporous CaO and a modified sorbent by washing with acetic acid. The capturing capacities of these sorbents are compared with CaO derived from natural limestone calcination. The solid conversion at 850°C after 3 h for the natural sorbent was only 5%, while this value was improved by up to 13 and 46% for acid-washed and nanosynthesised sorbents, respectively. The effect of various sorbent pore size distributions on SO₂ capture capacity is investigated.