Abstract. Conversion of natural gas to liquids (GTL) utilizing Fischer-Tropsch (FT) hydrocarbon synthesis technology is an attractive option to bring static gas resources to market. Since 1981, over $400M has been invested in research and development of Advanced Gas Conversion for the 21st Century (AGC-21)1. This state-of -the-art GTL technology provides an important commercial option for utilization of stranded natural gas located around the world. Continuing research at ExxonMobil is leading to additional technology improvements that will further reduce the cost of producing liquids from natural gas. This article discusses advances in ExxonMobil's AGC-21 technology achieved over the years as a result of an ongoing, comprehensive research, development and engineering program. synthesis gas is fed to a proprietary, advanced
INTRODUCTION Fischer-Tropsch Hydrocarbon Synthesis In the 1920's, Fischer and Tropsch (HCS) step, in which the H2 /CO synthesis gas discovered catalysts that promote the synthesis is converted to heavy hydrocarbons in the of liquid hydrocarbon and petrochemical presence of a high performance cobalt-based products from CO and H2.2 The technology catalyst, suspended in a novel slurry reactor. was first commercialized on a large scale by The full range, primarily linear paraffinic, the South African Coal, Oil and Gas Corp HCS product contains substantial levels of a (Sasol) in 1955, with the startup of a plant in 650oF+ boiling material which is solid at Sasolburg, in which the synthesis gas was ambient conditions and has a melting point produced by gasification of coal. The synthesis above 250oF. This material is converted to gas was fed to a circulating fluid bed reactor desired final products in a Hydroisomerization containing iron catalyst and reacted at high (HI) process that can be tailored to meet a temperature to produce olefinic chemical/ variety of product objectives. refinery plant feed for manufacture of chemicals, gasoline, and other fuel products.
Over the last decade, there has been renewed interest in the production of synthetic fuels via Fischer-Tropsch synthesis, using synthesis gas produced from remote natural gas. Emphasis is being placed on use of cobalt catalysts in fixed bed and slurry reactors to achieve high yields of paraffinic wax that can be readily converted to diesel, naphtha, lube basestocks and specialty products.
This interest has been driven by technology advances that are reducing the cost · Protected by Over 400 Patents in the U.S., 1500+ of converting large reserves of natural gas, not Worldwide, on Catalysts, Processes and Products readily accessible by pipeline, into high quality liquid fuel products. A large number of Fig