Investigation of the upgrading of Fischer-Tropsch waxes through hydroprocessing

Through the increasing role of renewable fuels in our daily lives their production and their improvement is a necessary step. Fischer-Tropsch synthesis based on renewable resources is one way to achieve this. The upgrading of its intermediates, known as Fischer-Tropsch waxes (FTW) can help to increase the economic viability of such a process by converting the waxes to pharmaceutical products or high value fuel additives. For each desired product regulations have to be reached (European Pharmacopoeia), certain benchmarks must be fulfilled, this ranges from viscosity to boiling point to the degree of isomerisation and the amount of byproducts in the mixtures. Especially aromatic components can pose a problem for pharmaceutical usage of the waxes. In this paper, the conversion of FTW via hydroprocessing was investigated, using a semi batch stirred-tank reactor. The focus lies on the conversion, the successiveness of the occurring reactions, the isomer content and the amount of formed aromatic compounds.292298

SYNTHESIS OF ALPHA-CYANO CARBONYL-COMPOUNDS BY FLASH VACUUM THERMOLYSIS OF (ALKYLAMINO)METHYLENE DERIVATIVES OF MELDRUMS ACID - EVIDENCE FOR FACILE 1,3-SHIFTS OF ALKYLAMINO AND ALKYLTHIO GROUPS IN IMIDOYLKETENE INTERMEDIATES

The syntheses and flash vacuum thermolyses of 5-[(alkylamino)methylene]-2,2-dimethyl-1,3-dioxane-4,6-diones (Meldrum's acid derivatives) 13a-i are described. Thermolysis of 13a as well as of ethyl 3-(tert-butylamino)acrylate (22) gives a tautomeric mixture of cyanoacetaldehyde (14) and 3-hydroxypropenenitrile (15). Thermolysis of 13b gives iminoacrolein 26 and not cyanoacetone (29). Thermolysis of 13c,d gives S-methyl cyanothioacetate (30), and 13f-h give cyanoacetamides 31 in high yields. 2-Cyanopent-4-enoic acid derivatives 32 are obtained from Meldrum's acids 13e,i. The results are discussed in terms of facile 1,3-shifts of methylthio and alkylamino groups in imidoylketenes, interconverting imidoylketenes and acylketene imines