Preparation of Fibrous CaO Sorbent by Hydrothermal Method

Using urea and calcium chloride as precipitator and calcium source, fibrous CaCO3 precursors were prepared using hydrothermal method, then fibrous CaO sorbent was obtained by calcination. The influence of hydrothermal temperature on CO2 absorption properties was discussed. X-ray diffraction analysis showed that pure CaCO3 phase with aragonite and calcite crystal forms was obtained. Scanning electron microscopy analysis showed that the resultant CaO sorbent presented a fibrous microstructure, which inherited the morphologies of CaCO3. The absorption capacity of the resultant CaO sorbent reached 59.86%, being 76% of theoretical absorption capacity. In addition, compared with the CaO sorbent from analytical pure CaCO3, the obtained fibrous CaO-sorbent have the better cyclic absorption properties.