Ag doping Fe-Ti spinel sorbent for Hg0 removal from syngas and the mechanism investigation

•Ag/Fe-Ti spinel presented higher than 90% Hg0 capture efficiency at 250 °C.•H2S was an effective syngas component responsible for Hg0 removal.•Ag enhanced the Hg0 removal performance at 250 °C without sulfur poisoning.•Hg0 removal over Ag/Fe-Ti spinel followed the Langmuir-Hinshelwood mechanism.•HgS and surface sulfur were formed on the surface of spent Ag/Fe-Ti spinel.