Chemical looping gasification of coal char with Cu-olivine oxygen carriers

A Cu-olivine oxygen carrier was prepared using impregnation method and used for steam gasification of coal char in a fixed bed reactor. It is shown that higher gasification temperature and steam/C molar ratio conduce to an increase in carbon conversion and syngas yield. The increase of CuO loading on the oxygen carrier and the oxygen carrier/char weight ratio leads to a higher carbon conversion but a lower syngas yield. The reaction activity of oxygen carrier has not been reduced after multiple regenerations at 950 ℃, which indicates that the olivine could inhibit the sintering of the supported Cu/CuO. The gasification at 800 ℃ in the presence of the oxygen carrier after 8th regeneration has a carbon conversion of 42.3%, a water conversion of 57.3% and a syngas yield of 2.12 L/(g·h).