A nanopore reactive adsorbent composite material, which may be a porous adsorbent, has a composition and microstructure, which integrates adsorbency, reactivity and catalysis. Integration may be achieved by modifying nanopore surfaces with dense ligand groups and by embedding at least one reactant phase effective to accomplish a sequence of reactions of which at least one reaction may be catalyzed by the surface ligand groups. The solid reactant phase may include reactive metal particles, such as, Mg, Sn, Al, Fe, or Zn, or mixtures thereof, and may be effective as in-situ reducing agent. A macroporous adsorbent, may be formed from the composite material. Recovery of mercury from a contaminated liquid is described. A second reactive phase, which may comprise a sulfur polymer or another metal effective to immobilize liquid mercury in-situ, may be included in or with the composite.