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I am interested in knowing more about the options of value addition to C4 stream produced in FCC / CDU.
C4 produced consists of a mixture of N-Butane, Iso-Butane and Butylenes.
Following value addition routes exist:
a) Recover Butylenes and convert them to Propylene using OCT (Olefins conversion technology).
b) Recover Butylenes, Isobutane and convert them to Alkylate in Alkylation.
c) Recover Iso-butane and use as a feed to Alkylation.
I would like to know if there are other routes of value addition available or any synergy with a Petrochemical complex. What are the options for N-Butane for value addition?
09/07/2011 A: Amarjit Bakshi, Refining Hydrocarbon Technologies LLC, abakshi@rhtgulfcoast.com
The other options are C4 chemistry itself so as to separate :
Butene which is used as monomer
Pure Isobutene for rubber production
Butenes for Butanol or OCT process
Additionally if MTBE can not be produced due to some sort of mandate like in USA, other option is to make isooctene/Isooctane from existing MTBE unit or new unit plus hydrogenation unit.
These are all based on need for these components in a petrochemical plant which is next door.
Naturally n-butane can be converted to isobutane as mentioned earlier if one has the alkylation unit where isobutane can be used depending on the refinery isobutane balance which normally epends on the size of alkylation unit
11/01/2011 A: R Balaji, LyondellBasell, r.balaji@lyondellbasell.com
I see this question is a year old. Have you received satisfactory answers or would you like to discuss options?
02/11/2010 A: G Saidulu, IOCL, saidulug@iocl.co.in
Other options could be (1) recycling of C4s to Naphtha catalytic cracking technologies such as Indalin of IOCL, Superflex of KBR (2) recycling of C4s to FCC riser (see patent application WO 2010/067379 A2) (3) convert i-C4= to MTBE/ETBE.
01/11/2010 A: Lindsay McRae, Pall Corporation, Lindsay_McRae@pall.com
n-C4 may be converted to i-C4 via isomerisation. Indeed, some process licensors integrate an isomerisation unit into alkylation unit to maximise i-C4 production and send it back to alky unit.
Feed preparation should be considered also. n-C4 feed to Isom needs to be free from water (and caustic) plus other contaminants so there is usually a dryer on n-C4 (with liquid coalescer to optimise the dryer performance) and there should be a high efficiency liquid gas coalescer (like Pall SepraSol LG) on the H2 feed stream to the ISOM protect the H2 dryer bed and catalyst.