Hydrocarbon Processing - May 2022 - 67

100th Anniversary
History of the HPI
LEE NICHOLS, Editor-in-Chief/Associate Publisher
The 1960s: Synthetic oils, zeolite catalysts,
LLDPE, OPEC and and creation of the PLC
During the 1960s, the global refining
and petrochemical industries witnessed
new processes and products that
enhanced the daily lives of millions of
people around the world. The decade
was responsible for the creation of new
petrochemical products to provide better
and more durable goods within many industrial
sectors and consumer goods applications.
Other innovations, such as the
creation of synthetic oils and synthetic
zeolite catalyst, enhanced processing operations
and engine/fuel performance in
the automobile and aviation sectors. The
1960s was also a prominent decade for
LNG trade [the first transatlantic LNG
cargo was carried on the Methane Pioneer
in early 1959 from Constock's LNG production
facility in Louisiana (U.S.) to the
UK; the UK also received the world's first
commercial LNG cargo from Shell's Methane
Pioneer vessel in October 1964 from
Algeria; LNG exports from Alaska (U.S.)
to Japan commenced in the late 1960s],96
the creation of the programmable logic
controller (PLC)-a significant evolution
in automation-and the creation of
the Organization of Petroleum Exporting
Countries (OPEC), which was, and still
is, a major force in setting global oil prices.
Creation and widespread adoption
of synthetic oils. Although the first synthetic
hydrocarbon oils were produced
in 1877 by French chemist Charles Friedel
and American chemist James Mason
Crafts (i.e., Friedel-Crafts alkylation and
acylation reactions), synthetic oils did
not see widespread adoption until postWorld
War 2 (WW2).
Prior to WW2, several individuals developed
new reactions to produce synthetic
oils. These included German scientists
Friedrich Bergius, Franz Fischer and Hans
Tropsch (the Bergius and Fischer-Tropsch
processes were detailed in the History of
the HPI segments published in the January
and March issues of Hydro carbon Processing),
as well as American researcher
F. W. Sullivan while working at Standard
Oil of Indiana (U.S.). Sullivan's team tried
to commercialize synthetic oils in 1929;
however, this attempt was challenged due
to lack of demand. Regardless, Sullivan
published a paper in 1931 titled " Synthetic
lubricating oils relation between chemical
constitution and physical properties, "
which, along with research from the German
chemist Hermann Zorn, provided a
foundation for the future widespread use
of synthetic oils in the aviation and the automobile
sectors-Zorn and his team researched
more than 3,500 synthetic esters
during the early 1940s to find an alternative
to petroleum oil to help fuel Germany's
war machine.97,98
The need for synthetic oils did not
materialize until Germany's invasion of
the Soviet Union during WW2. During
the Battle of Stalingrad, the harsh Russian
winter demobilized German tanks,
fighter planes and other military vehicles.
The main culprit: temperature. Conventional
petroleum oil could not stand
up to the frigid temperatures during the
harsh Russian winter. These oils were
produced through conventional distillation,
which has several drawbacks, including
solidifying in low temperatures,
rendering its use extremely ineffective in
extremely cold environments-conventional
distillation could not completely
remove impurities such as waxes, which
would solidify in cold temperatures, leading
to the inability of engines to start.98
This event demonstrated that a new form
of lubricating oil was needed.
The use of synthetic oils found its demand
within aircraft engines during and
post-WW2. While Zorn was conducting
widescale tests on different synthetic
esters in Germany, American chemist
William Albert Zisman was researching
synthetics at the Naval Research Laboratory
in Washington D. C. (U.S.). His work
(1942-1945)-detailed in the technical
article " Synthetic lubricant fluids from
branched-chain
diesters
chemical properties of pure diesters, " 99
physical and
-
led to the development of the first diester
synthetic base oils, a precursor to the
development of modern synthetic lubricants.98,100
With
the creation of the jet
engine in the 1940s (the history of the jet
engine was detailed in the History of the
HPI segment published in the February
issue of Hydrocarbon Processing), synthetic
oils were able to protect engine components
against extreme temperatures during
flight, a challenge that conventional
oils could not accomplish. As a result,
FIG. 1. Albert Amatuzio developed the
world's first synthetic motor oil to meet
API service requirements. For this, he is
known as a pioneer in synthetic lubrication.
Photo courtesy of AMSOIL.
Hydrocarbon Processing | MAY 2022 67

Hydrocarbon Processing - May 2022

Table of Contents for the Digital Edition of Hydrocarbon Processing - May 2022

Contents
Hydrocarbon Processing - May 2022 - Cover1
Hydrocarbon Processing - May 2022 - Cover2
Hydrocarbon Processing - May 2022 - Contents
Hydrocarbon Processing - May 2022 - 4
Hydrocarbon Processing - May 2022 - 5
Hydrocarbon Processing - May 2022 - 6
Hydrocarbon Processing - May 2022 - 7
Hydrocarbon Processing - May 2022 - 8
Hydrocarbon Processing - May 2022 - 9
Hydrocarbon Processing - May 2022 - 10
Hydrocarbon Processing - May 2022 - 11
Hydrocarbon Processing - May 2022 - 12
Hydrocarbon Processing - May 2022 - 13
Hydrocarbon Processing - May 2022 - 14
Hydrocarbon Processing - May 2022 - 15
Hydrocarbon Processing - May 2022 - 16
Hydrocarbon Processing - May 2022 - 17
Hydrocarbon Processing - May 2022 - 18
Hydrocarbon Processing - May 2022 - 19
Hydrocarbon Processing - May 2022 - 20
Hydrocarbon Processing - May 2022 - 21
Hydrocarbon Processing - May 2022 - 22
Hydrocarbon Processing - May 2022 - 23
Hydrocarbon Processing - May 2022 - 24
Hydrocarbon Processing - May 2022 - 25
Hydrocarbon Processing - May 2022 - 26
Hydrocarbon Processing - May 2022 - 27
Hydrocarbon Processing - May 2022 - 28
Hydrocarbon Processing - May 2022 - 29
Hydrocarbon Processing - May 2022 - 30
Hydrocarbon Processing - May 2022 - 31
Hydrocarbon Processing - May 2022 - 32
Hydrocarbon Processing - May 2022 - 33
Hydrocarbon Processing - May 2022 - 34
Hydrocarbon Processing - May 2022 - 35
Hydrocarbon Processing - May 2022 - 36
Hydrocarbon Processing - May 2022 - 37
Hydrocarbon Processing - May 2022 - 38
Hydrocarbon Processing - May 2022 - 39
Hydrocarbon Processing - May 2022 - 40
Hydrocarbon Processing - May 2022 - 41
Hydrocarbon Processing - May 2022 - 42
Hydrocarbon Processing - May 2022 - 43
Hydrocarbon Processing - May 2022 - 44
Hydrocarbon Processing - May 2022 - 45
Hydrocarbon Processing - May 2022 - 46
Hydrocarbon Processing - May 2022 - 47
Hydrocarbon Processing - May 2022 - 48
Hydrocarbon Processing - May 2022 - 49
Hydrocarbon Processing - May 2022 - 50
Hydrocarbon Processing - May 2022 - 51
Hydrocarbon Processing - May 2022 - 52
Hydrocarbon Processing - May 2022 - 53
Hydrocarbon Processing - May 2022 - 54
Hydrocarbon Processing - May 2022 - 55
Hydrocarbon Processing - May 2022 - 56
Hydrocarbon Processing - May 2022 - 57
Hydrocarbon Processing - May 2022 - 58
Hydrocarbon Processing - May 2022 - 59
Hydrocarbon Processing - May 2022 - 60
Hydrocarbon Processing - May 2022 - 61
Hydrocarbon Processing - May 2022 - 62
Hydrocarbon Processing - May 2022 - 63
Hydrocarbon Processing - May 2022 - 64
Hydrocarbon Processing - May 2022 - 65
Hydrocarbon Processing - May 2022 - 66
Hydrocarbon Processing - May 2022 - 67
Hydrocarbon Processing - May 2022 - 68
Hydrocarbon Processing - May 2022 - 69
Hydrocarbon Processing - May 2022 - 70
Hydrocarbon Processing - May 2022 - 71
Hydrocarbon Processing - May 2022 - 72
Hydrocarbon Processing - May 2022 - 73
Hydrocarbon Processing - May 2022 - 74
Hydrocarbon Processing - May 2022 - 75
Hydrocarbon Processing - May 2022 - 76
Hydrocarbon Processing - May 2022 - 77
Hydrocarbon Processing - May 2022 - 78
Hydrocarbon Processing - May 2022 - 79
Hydrocarbon Processing - May 2022 - 80
Hydrocarbon Processing - May 2022 - 81
Hydrocarbon Processing - May 2022 - 82
Hydrocarbon Processing - May 2022 - 83
Hydrocarbon Processing - May 2022 - 84
Hydrocarbon Processing - May 2022 - 85
Hydrocarbon Processing - May 2022 - 86
Hydrocarbon Processing - May 2022 - 87
Hydrocarbon Processing - May 2022 - 88
Hydrocarbon Processing - May 2022 - 89
Hydrocarbon Processing - May 2022 - 90
Hydrocarbon Processing - May 2022 - Cover3
Hydrocarbon Processing - May 2022 - Cover4
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
https://www.nxtbook.com/gulfenergyinfo/gulfpub/gas-processes-handbook-2022
https://www.nxtbook.com/gulfenergyinfo/gulfpub/hp_202212
https://www.nxtbook.com/gulfenergyinfo/gulfpub/hpi-market-data-2023-v2
https://www.nxtbook.com/gulfenergyinfo/gulfpub/hpi-market-data-2023
https://www.nxtbook.com/gulfenergyinfo/gulfpub/hp_202211
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202210
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202209
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202208
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202207_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202207
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202206_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202206
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202205_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202205
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202204_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202204
https://www.nxtbook.com/nxtbooks/gulfpub/hp_032022
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202203
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202202
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202201
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202112
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202111
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202110
https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2022_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2022
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
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202106
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202105
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202104
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
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202003
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202002
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
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201908
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201907
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201906
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201905
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201904
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201903
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201902
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
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201809
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201808
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201807
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201806
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201805
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201804
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201803
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
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201710
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201709
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201708
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201707
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201706
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201705
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201704
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201703
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201702
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
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201608
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201607
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201606
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201605
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201604
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201603
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201602
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201601
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201512
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201511
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201510
https://www.nxtbook.com/nxtbooks/gulfpub/hp_2016mediaplanner
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201509
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201508
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201507
https://www.nxtbook.com/nxtbooks/gulfpub/hp_2015tmsd
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201506
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201505
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201504
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201503
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201502
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201501
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201412
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201411
https://www.nxtbook.com/nxtbooks/gulfpub/hp_2015mediaplanner
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201410
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201409
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201408
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201407
https://www.nxtbook.com/nxtbooks/gulfpub/hp_2014petrochemicalprocesses_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hp_2014petrochemicalprocesses
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201406
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201405
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201404
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201403
https://www.nxtbook.com/nxtbooks/gulfpub/hp_2014calendar
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201402
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201401
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201312
https://www.nxtbook.com/nxtbooks/gulfpub/hp_2014mediaplanner
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201311
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201310
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201309
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201308
https://www.nxtbook.com/nxtbooks/gulfpub/hp_srsguide2013
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201307
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201306
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201305
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201304
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201303
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201302
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201301
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201212
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201211
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201210
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201209
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201208
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201207
https://www.nxtbook.com/nxtbooks/gulfpub/hp_srsguide2012
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201206
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201205
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201204
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201203
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201202
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201201
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201112
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201111
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201110
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201109
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201108
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201107_srsguide
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201107
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201106
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201105
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201104
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201103
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201102
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201101
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201012
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201011
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201010
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201009
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201008
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201007
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201006
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201005
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201004
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201003
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201002
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201001
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200912
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200911
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200910
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200909
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200908
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200907
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200906
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200905
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200904
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200903
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200902
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200901
https://www.nxtbookmedia.com