The research in room temperature ionic liquid is reviewed. The present status and development prospect of its applications to environmental chemistry are introduced in detail. As high performance environmental solvents, the room temperature ionic liquids can be applied to treating oil shale, purifying nature gas, and processing nuclear fuel; they can also be used in organic synthesis reactions, such as Diels Alder reaction, Friedel Crafts reaction, transition metal catalyzed reaction, regioselective alkylation. They can be used as the substitutes for traditional strong acid catalysts in alkylation of polycyclic aromatic hydrocarbon, esterification of acetic acid with alcohols, Beckmann rearrangement reaction, hydrogenation and polymerization of aromatic compounds.
