Hydrocarbon Processing - April 2021 - 39

Clean Fuels
acts as a temporary poison by occupying an acid site, which
then becomes unavailable for alkylation.
However, the proprietary catalyst-which is zeolitic in nature-can remove these contaminants without the need for
extensive pretreatment. These contaminants-which remain
adsorbed on the catalyst surface-are removed during the regular regeneration procedure, allowing the catalyst to recover its
full activity. This unique feature has important consequences
for Tier 3 regulations. Even though the olefinic feedstocks may
contain sulfur or oxygenates, the alkylate produced is essentially sulfur and oxygenate free (FIG. 3).
Performance with feed contaminants. Equally important

is the quality of alkylate produced for feedstocks containing
high levels of contaminants. There is no change in the quality
of alkylate produced for feedstocks with high levels of contaminants for a mixed C3 and C4 olefin feed (TABLE 3).
Proprietary solid-acid alkylation processb design. A
unit process diagram of the proprietary process is shown in
FIG. 4. In the reaction zone, isobutane and olefins are reacted
to produce alkylate. The reaction takes place over the solidacid catalyst in fixed-bed reactors. Three fixed-bed reactors
with recirculation are used in the reaction section. Two are
used for alkylation, while the other is being regenerated in a
staggered cycle. The reactors typically contain multiple beds,
with olefin feed spargers between each bed. A portion of the

olefin feed and the reactor recirculation stream are combined
and introduced at the top of the reactor.
The alkylation reaction is mildly exothermic. The reaction's
heat is removed by a heat exchanger located in the recirculation
loop outside the reactor. As in conventional alkylation units,
the reactor effluent is sent to a distillation train consisting of
two columns. First, a deisobutanizer is used to recover excess
isobutane, which is returned to the reactor. Excess n-butane
is removed from the alkylate product in this column, as well.
Second, a depropanizer is used to remove light components-
mainly propane-from the system. The proprietary process
does not require any neutralization or washing equipment to
post-treat the alkylate product.
At the end of the 24-hr alkylation cycle, the feeds are switched
to the newly regenerated reactor, and the catalyst in the previous
(i.e., in-service) reactor is regenerated. A vapor-phase circulating loop containing hydrogen and light hydrocarbons is used to
heat the reactor to about 275°C (527°F), at which point catalyst regeneration occurs. Due to the small amount of soft-coke
buildup during the reaction cycle, hydrogen consumption is low.
After 2 hr at this condition, the loop is used to cool the reactor
to the reaction temperature. Fresh isobutane is charged to the
reactor, making the reactor ready for the next alkylation cycle.
This sequence is controlled by a programmable logic controller.
Techno-economic analysis. Due to lower capital costs and
a higher alkylate margin, the proprietary solid-acid alkylation

2021 SPRING REFINING
AND EQUIPMENT
STANDARDS MEETING
MAY 10-20, 2021 | API VIRTUAL EVENT

Join API for the 2021 Spring Refining And
Equipment Standards Meeting to learn about
the latest research and development on
refining process equipment, including future
R&D efforts.
This meeting will be presented in a fully,
virtual format and will be open to anyone
who wishes to participate.

Register at www.API.org/springrefining

Copyright 2021 - American Petroleum Institute, all rights reserved. API and the API logo are
either trademarks or registered trademarks of API in the United States and/or other countries.

Hydrocarbon Processing | APRIL 2021

39


http://www.API.org/springrefining

Hydrocarbon Processing - April 2021

Table of Contents for the Digital Edition of Hydrocarbon Processing - April 2021

Contents
Hydrocarbon Processing - April 2021 - Cover1
Hydrocarbon Processing - April 2021 - Cover2
Hydrocarbon Processing - April 2021 - Contents
Hydrocarbon Processing - April 2021 - 4
Hydrocarbon Processing - April 2021 - 5
Hydrocarbon Processing - April 2021 - 6
Hydrocarbon Processing - April 2021 - 7
Hydrocarbon Processing - April 2021 - 8
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Hydrocarbon Processing - April 2021 - Cover3
Hydrocarbon Processing - April 2021 - Cover4
Hydrocarbon Processing - April 2021 - GP-1
Hydrocarbon Processing - April 2021 - GP-2
Hydrocarbon Processing - April 2021 - GP-3
Hydrocarbon Processing - April 2021 - GP-4
Hydrocarbon Processing - April 2021 - GP-5
Hydrocarbon Processing - April 2021 - GP-6
Hydrocarbon Processing - April 2021 - GP-7
Hydrocarbon Processing - April 2021 - GP-8
Hydrocarbon Processing - April 2021 - GP-9
Hydrocarbon Processing - April 2021 - GP-10
Hydrocarbon Processing - April 2021 - GP-11
Hydrocarbon Processing - April 2021 - GP-12
Hydrocarbon Processing - April 2021 - GP-13
Hydrocarbon Processing - April 2021 - GP-14
Hydrocarbon Processing - April 2021 - GP-15
Hydrocarbon Processing - April 2021 - GP-16
Hydrocarbon Processing - April 2021 - GP-17
Hydrocarbon Processing - April 2021 - GP-18
Hydrocarbon Processing - April 2021 - GP-19
Hydrocarbon Processing - April 2021 - GP-20
Hydrocarbon Processing - April 2021 - GP-21
Hydrocarbon Processing - April 2021 - GP-22
Hydrocarbon Processing - April 2021 - GP-23
Hydrocarbon Processing - April 2021 - GP-24
Hydrocarbon Processing - April 2021 - GP-25
Hydrocarbon Processing - April 2021 - GP-26
Hydrocarbon Processing - April 2021 - GP-27
Hydrocarbon Processing - April 2021 - GP-28
Hydrocarbon Processing - April 2021 - GP-29
Hydrocarbon Processing - April 2021 - GP-30
Hydrocarbon Processing - April 2021 - GP-31
Hydrocarbon Processing - April 2021 - GP-32
Hydrocarbon Processing - April 2021 - GP-33
Hydrocarbon Processing - April 2021 - GP-34
Hydrocarbon Processing - April 2021 - GP-35
Hydrocarbon Processing - April 2021 - GP-36
Hydrocarbon Processing - April 2021 - GP-37
Hydrocarbon Processing - April 2021 - GP-38
Hydrocarbon Processing - April 2021 - GP-39
Hydrocarbon Processing - April 2021 - GP-40
Hydrocarbon Processing - April 2021 - GP-41
Hydrocarbon Processing - April 2021 - GP-42
Hydrocarbon Processing - April 2021 - GP-43
Hydrocarbon Processing - April 2021 - GP-44
https://www.nxtbook.com/gulfenergyinfo/gulfpub/HPI-Market-Data-2023-v3
https://www.nxtbook.com/gulfenergyinfo/gulfpub/hpi-market-data-2024-v2
https://www.nxtbook.com/gulfenergyinfo/gulfpub/hpi-market-data-2024
https://www.nxtbook.com/gulfenergyinfo/gulfpub/gas-processes-handbook-2022_v2
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https://www.nxtbook.com/gulfenergyinfo/gulfpub/hp_202212
https://www.nxtbook.com/gulfenergyinfo/gulfpub/hpi-market-data-2023-v2
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https://www.nxtbook.com/gulfenergyinfo/gulfpub/hp_202211
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_202109
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202108
https://www.nxtbook.com/nxtbooks/gulfpub/petrochemical_processes_handbook_2021_v2
https://www.nxtbook.com/nxtbooks/gulfpub/petrochemical_processes_handbook_2021
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202107
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_ebooks
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202103
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202102
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202101
https://www.nxtbook.com/nxtbooks/gulfpub/catalyst_handbook_2020_v2
https://www.nxtbook.com/nxtbooks/gulfpub/catalyst_handbook_2020
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202012
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202011
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202010
https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2021
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202009
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202008
https://www.nxtbook.com/nxtbooks/gulfpub/refining_processes_handbook_2020
https://www.nxtbook.com/nxtbooks/gulfpub/refining_processes_handbook_2020_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202007
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202006
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202005
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202004
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_202001
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201912
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201911
https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2020_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2020
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201910
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201909
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201901
https://www.nxtbook.com/nxtbooks/gulfpub/petrochemical_2018_v2
https://www.nxtbook.com/nxtbooks/gulfpub/petrochemical_2018
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201812
https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2019_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2019
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201811
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201810
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201804
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201802
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201801
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201712
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201711
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201709
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201705
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201704
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201701
https://www.nxtbook.com/nxtbooks/gulfpub/hp_2017mediaplanner
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201612
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201611
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201610
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201609
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