Sulfolane, originally developed by Arco and Shell in the 1960s, has become the leading benzene, toluene and xylenes (BTX) extraction technology due in a large part to HRI (now Axens North America) research, licensing efforts, experience and engineering expertise. The most up-to-date Arco-based technology, available through Axens, has many outstanding features, among which is the ability to design for a wide spectrum of feedstocks along with high BTX recovery, product purity and operating efficiency.

Over twenty licensed units are operating around the world with the most recent licensees in Brazil, India, and Thailand. Commercial units are operating on pyrolysis gasoline, BT and BTX reformate, Coke Oven Light Oils, mixtures of the above and straight run naphtha for jet fuel smoke point improvement.