This review is an update of previous reviews dealing with the Sasol process, the catalysts used, the control of selectivity, the kinetics and the mechanism of the F-T reaction. The emphasis is on the practical aspects. With regard to reactor developments two new types have now been put into commercial production, namely a 45 bar multi-tubular fixed bed reactor for wax production and an alternative type of fluidised bed reactor for light oil production. The latter reactor costs much less to construct and to operate than the older circulating fluidised bed reactors. The slurry phase reactor concept is now entering the demonstration size stage of development. Improved olefin oligomerisation catalysts have resulted in a better quality diesel fuel being made in downstream upgrading. The best way of producing maximum and high quality diesel is to maximise wax production and then to selectivity hydrocrack it. A comparison is made between the two existing Sasol processes and the proposed Shell Middle Distillate process.
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