Abstract: In order to reduce the impact of rare earth tailings（RET）on the ecological environment and achieve the RET recycling，the ion-absorbing type RET was used as the main raw material for preparing the porous non-sintered ceramsite.The effects of binding material，activating agent and foaming agent amount on ceramsite performance were studied.Scanning electron microscope（SEM）was used to characterize the microstructure of the representative ceramsite.Results showed that the best formula for preparing the ceramsite with the ion type rare earth tailings was 76% RET，10% cement，8% quicklime，2% aluminum powder；Performance indicators of the ceramsite prepared were as follows:water absorption（W）was 30.28%，apparent porosity（P）rate was 49.96%，density（D）was 1.65 g/cm³，and compressive strength was 3.17 MPa；SEM analysis showed that the hole in the ceramsite was well-developed and calcium silicate hydrate（CSH）was generated on the surface of the particle.The study indicates that it is feasible for preparing the porous non-sintered ceramsite with the ion-absorbing type RET as main source material.

Key words: Rare earth tailings, Porous non-sintered ceramsite, Formula for raw material