Sodium 2-anthraquinonesulfonate (AMS) is a water-soluble anthraquinone derivative. In the laboratory it can be prepared by sulfonation of anthraquinone.[1]
AMS is used as a catalyst in the production of alkaline pulping in the soda process. It goes through a redox cycle similar to that of anthraquinone to give a catalytic effect. AMS was discovered as an efficient pulping catalyst before anthraquinone,[2] but has a higher cost.