Selective Synthesis of Higher Linear α-olefins over Cobalt Fischer–Tropsch Catalyst

Abstract

An efficient approach for more selective synthesis of higher linear a-olefins was achieved by utilizing suitable reaction media in FTS reaction. About 41.4% average a-olefins content in C 5 -C 25 fractions was obtained at W/F ðCOþH2Þ =5 g-cat h mol )1 in n-C 10 solvent, which is markedly higher than the value (2.5%) obtained in 85% N 2 +15% n-C 6 .

Catalytic Decarbonylation of Biosourced Substrates

“…The two main commercial processes to obtain LAO are the oligomerization of ethylene [1][2][3][4][5][6] and the Fischer-Tropsch process starting from syngas. [7][8][9][10][11] However, these presents ome drawbacks such as lower yields of longchain LAO (C 10 -C 14 )c ompared to short-chain LAO (C 4 -C 8 )c oupled with ad ecrease in selectivity because of the formation of branched olefins and isomerization reactions. The production of LAO with an odd number of carbon atoms appears to be impossible by ethylene oligomerization.…”

Correlation between Hydrocarbon Product Distribution and Solvent Composition in the Fischer–Tropsch Synthesis Catalyzed by Colloidal Cobalt Nanoparticles

“…The cobalt nanoparticles Co1 were synthesized in water by chemical reduction of CoCl 2 ·6H 2 O in the presence of NaBH 4 using PVP as stabilizer (PVP:Co = 20) while Co2 were produced by thermal decomposition of Co 2 (CO) 8 in butylether at 150°C in the presence of 10 equiv of PVP. In this latter case, the amount of PVP was lower than for the chemical reduction method due to solubility issues.…”

“…Co2 was synthesized by thermal decomposition of Co 2 (CO) 8 in the presence of the PVP (PVP:Co ratio of 10) using butylether as solvent. As a standard procedure, 0.352 g of Co 2 (CO) 8 (1.86 mmol) and 2.066 g of PVP (18.6 mmol based on monomer units, PVP:Co ratio of 10) were placed in a 500 mL Fischer−Porter bottle and dissolved with 130 mL of butyl ether. The Fischer−Porter bottle was closed and then heated at 150°C during 2 h to give a black suspension.…”

“…The same group reported the effect of solvent on the selectivity to long chain linear α-olefins over cobalt Fischer−Tropsch catalysts. 8 Interestingly, ca. 40% selectivity to α-olefins was obtained in the presence of n-decane, in comparison to ca.…”

“…16 Other colloidal Co nanocatalysts for FTS were reported in ionic liquids 17 and squalane 18 although in these cases generally low activity and agglomeration issues were described. Dupont and co-workers reported the synthesis of Co nanocubes (54 ± 22 nm) 17a and nanospheres (7.7 ± 1.2 nm) 17b by thermal decomposition of Co 2 (CO) 8 19 The isolated bimetallic NPs resulted in active catalysts for the Fischer−Tropsch synthesis, with selectivity for naphtha products.…”