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I am working on a process for aviation fuel and gasoline production from biomass gasification via Fischer-Tropsch synthesis using cobalt based catalyst.

I would like some insights on how to convert the Fischer-Tropsch wax (C5-C40 both paraffins and olefins) to Aviation fuel and Gasoline. Do we need to use both hydrotreating and hydrocracking? Will it be different compared to gas-oil hydrotreating?
31/03/2020 A: Sridhar Balakrishnan, Bharat Oman Refineries Limited , laksrid@yahoo.com
Firstly it can be hydrocracked. Then fractionation or distillation can be done to separate the fuel cuts. The gasoline range product has to be isomerized or hydroisomerized to remove or convert the paraffins. But for jet fuel range product, a conventional refinery process can be used to remove the paraffin content.
27/03/2020 A: Jake Gotham, InSite Technical Services, jake.gotham@insitetechnical.com
Unfortunately, Fischer-Tropsch has poor selectivity, and the product will have a broad range of molecule sizes. You may be able to separate useful products by distillation, but you are correct to suggest hydrocracking would enable you to crack the larger molecules back into a more useful boiling range with good selectivity. This approach has been in commercial operation for many years at several sites. Hydrotreating alone would stabilise the product (i.e. saturate the olefins) but would not give you a useful aviation or road fuel product without separation or cracking.
To answer your last question, hydrocracking and hydrotreating are similar technologies. The catalyst is different, the operating pressure is higher for hydrocracking, equipment sizes are different, and a distillation section is required in a hydrocracking unit.
Eurotek will be presenting a hydrocracking course once the Coronavirus travel restrictions are lifted. Register your interest by emailing enquiries@eurotek-refining.co.uk if you think you would find it useful.
26/03/2020 A: Eric Vetters, ProCorr Consulting Services, ewvetters@yahoo.com
Yes you have to hydrotreat/hydrocrack the FT liquids then fractionate into the desired boiling ranges. The hydrotreating step is much easier than most gas oil processes because you are primarily removing oxygenates, which are easy to treat.

Naphtha will need to go through a catalytic reformer and isomerization unit to make gasoline. I’m not sure but the jet fuel may need to go through an isodewaxing process to reduce the normal paraffin content.