Novel Design of an Integrated Pulp Mill Biorefinery for the ...

Figure 9: Product distribution for different α for the FT synthesis [82].
The exact path involved in the growth of hydrocarbons during Fischer-Tropsch synthesis
is uncertain. It is generally accepted that growth occurs by a stepwise growth of polymerization
of monomers [71, 72, 75]]. Figure 10 illustrates the chain growth process.
Figure 10: FT stepwise growth process.
The Figure 2.4.4 illustrates the chain growth process where monomers are absorbed by
surface -CH2- units and produce only hydrocarbons. The growth is dependent on α, the growth
probability chain, where it has three possible outcomes. It may desorb an alkene, hydrogenate to
desorb an alkane or continue to the chain growth process by adding another CH2 unit [72, 73].
Fischer-Tropsch synthesis grows chains in ranging from C1 (methane) to C60 (heavy waxes).
Table 7 gives hydrocarbons by carbon number and their associated names.
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