Download Report

Special Report
PRODUCT FOCUS
Isopropyl alcohol: A techno-commercial profile
I
Introduction
sopropyl alcohol (Isopropanol,
IPA) is a colourless, flammable liquid with a characteristic alcohol /
acetone-like odor. It mixes completely
with most solvents, including water.
PANKAJ DUTIA
pankaj@chemicalweekly.com
this had fallen to 4.5%. It disappeared
completely in the late 1990s. ExxonMobil, the world’s leading manufacturer of IPA, for example, has quit making acetone from the IPA route. Acetone demand can now be entirely satisfied by the co-product material from
the cumene/phenol process; indeed in
certain cases now, IPA is made from
acetone.
ducts (e.g., general purpose cleaners, disinfectants, room sprays);
Paints and inks (e.g. nitrocellulosebased lacquers and thinners for
wood finishing, adhesives);
Pharmaceuticals (e.g., as an extractive solvent);
Medical applications (e.g., for sterilising and disinfecting surfaces in
hospitals; preserving biological
specimens and to impregnate sterilized cleaning wipes used for sanitising telephone handsets etc.);
Screen wash and de-icers;
In food industry (e.g. in pectin extraction); and
Foundry resins.
Use as solvent
IPA is a popular solvent used as
such in:
Personal care and household pro-
In the coatings industry, IPA is
mainly used as an inert solvent to reduce the flammability of coatings during storage and transportation. In inks,
IPA is one of the most widely used
solvents in the world. It is also used as
a chemical intermediate.
One well-known, yet relatively
small use for IPA is “rubbing alcohol,”
which is a mixture of IPA and water and
can be purchased in many pharmacies
and grocery stores.
Applications
IPA was historically used for making acetone, but use in this application
has been hit by the reduction in use of
acetone as a solvent as a result of legislation on air pollution. During the
1980s, acetone from IPA accounted on
average for about 8% of acetone production in the United States. By 1990,
Table 1
Use of IPA as a solvent
Function
Process solvent
Coating and dye solvent
Cleaning and drying agent
Solvent in topically applied
preparations
Aerosol solvent
Application
Extraction and purification of natural products, such as vegetable and animal oils and
fats, gums, resins, waxes, colours, flavourings, alkaloids, vitamins, kelp and alginates
Carrier in the manufacture of food products
Purification, crystallization and precipitation of organic chemicals
Synthetic polymers such as phenolic varnishes & NC lacquers
Cements, primers, paints and inks
Manufacture of electronic parts, for metals & photographic films and papers, in glass
cleaners, liquid soaps & detergents, aerosols
Pharmaceutical products: topically applied rubbing alcohol
Cosmetics: hair tonics, perfumes, skin lotions, hair dye rinses, permanent wave lotions,
skin cleaners & deodorants, nail polish, shampoos
Cleaners, waxes, polishes, paints, de-icers, shoe and sock sprays, insect repellants, hair
sprays, deodorants, air-fresheners
Medical and veterinary products: antiseptics, foot fungicides, first aid & medical vapour
sprays, skin soothers, house & garden type insecticides
Chemical Weekly April 24, 2012
211
Special Report
IPA is mainly used as an additive and
thinner of water-based paints.
IPA has many uses in the pharmaceutical field. As a major raw material,
IPA is used to produce many pharmaceutical intermediates, such as 7-aminocephalosporanic acid (7-ACA), iohexol
and chloramphenicol. IPA can also be
used to produce amoxicillin, piracetam,
isopropyl aluminum (catalyst), and so
on. In 2010, the pharmaceutical industry consumed about 46,000 tons of IPA.
It is expected that in 2015, the demand
for IPA in the pharmaceutical field will
reach 78 000 tons, with an average annual growth rate of 8%.
Chemical derivatives
Solvent use is much larger than as a
chemical intermediate, but the latter is
also important.
IPA is used for making downstream
derivatives such as:
Isopropyl ether, which finds in the
cosmetics and personal care industry;
Isopropyl esters, for use as a solvent
in cellulosics and inks;
Isopropyl amines, for use in the
manufacture of glyphosate herbicides;
IPA reacts with carbon disulphide
to give sodium isopropylxanthate, a
weed killer.
IPA reacts with titanium tetrachloride and aluminium metal
to give titanium and aluminium
isopropoxides respectively, the
former a catalyst, and the latter a
chemical reagent. This compound
may serve as a chemical reagent
in itself, by acting as a dihydrogen donor in transfer hydrogenation.
Diisopropyl ether (DIPE)
DIPE is prepared from IPA in
liquid phase in contact with particular Montmorillonite clay catalysts,
optionally in the presence of added
propylene. The process is operated
in a continuous manner by continu-
ously feeding liquid IPA, optionally
with added propylene, into a reaction
space where the feed contacts the
catalyst at 120-250°C for an average contact time of 1 to 120 minutes.
Pressure is maintained in the reactor
to keep a liquid phase in contact with
the solid catalyst. Effluent withdrawn
continuously from the reaction space
at the feed rate is separated by fractionation to recover DIPE.
Isopropyl esters
Isopropyl esters find main applications in the personal care industries.
Isopropyl laurates are used as cosmetics and lubricating oil additives.
Isopropyl myristate is used as an
emollient and lubricant in preshaves, after-shaves, shampoos,
bath oils, antiperspirants, deodorants, and various creams and
lotions.
Isopropyl palmitate is used in cosmetics as a thickening agent and
emollient. It is often used in mois-
Isopropyl myristate/
Isopropyl palmitate
Isopropyl alcohol
C14/ C16 Fatty acid
Soap/Water
Residue
Water
Esterification
Alcohol
distillation
Neutralizing
Product
distillation
Fig. 1: Process flow diagram for preparation of isopropyl esters
212
Chemical Weekly April 24, 2012
Special Report
turisers where it forms a thin layer
and easily penetrates the skin.
Isopropyl palmitate is said to enhance silkiness in hair and skin.
The isopropyl esters of carboxylic
acids are manufactured by reacting the
corresponding fatty acid with IPA. The
by-product of the esterification reaction
is water.
Isopropyl amines
As a chemical raw material, monoisopropylamine (MIPA) has very versatile applications including production
of pesticides (such as atrazine, prometryn, glyphosate isopropylamine
salt, and bentazone), intermediates for
pharmaceuticals and dyestuffs, rubber accelerators, hard water treatment
agents and detergents.
Health information
Under usual conditions of exposure,
IPA is quickly converted to acetone
once taken into the body. Acetone is naturally present in
virtually every organ and tissue in the human body as a
result of metabolic processes.
place or the environment. Over-exposure to IPA can cause irritation to the
eyes, nose and throat, and may produce central nervous system depression. These effects are typically mild
and end shortly after exposure is terminated, not showing any permanent
adverse health affects. Swallowing
small amounts is not likely to cause
injury; however swallowing larger
amounts may cause serious injury, and
even death.
Chronic, prolonged or repeated
overexposure to IPA has produced adverse liver effects and kidney effects
and/or tumours in male rats. Such effects are believed to be species-specific, however, and unlikely to occur in
humans.
Public and wildlife exposure
through environmental releases is limited because IPA rapidly biodegrades in
water and undergoes photo-oxidation
Toxicology studies have
shown that IPA poses a low
health hazard and does not
cause adverse health or environmental effects at levels
typically found in the workTable 2
Specifications of IPA of Deepak Fertilisers
Properties
Purity
Residue
Water content
Miscibility with water
Acidity as acetic acid
Color hazen units
Distillation range
Specific gravity @ 25°C
Specifications
99.7% to 99.9% w/w
12 ppm w/w max
650 ppm w/w max
Complete
10 ppm w/w max
10 max
81.5 to 83
0.782 - 0.784
Chemical Weekly April 24, 2012
Test method
GC
IS 517 1986
ASTM D 1364
ASTM D 1722
ASTM D 1613
ASTM D 1209
ASTM D 1078
ASTM D 891
relatively rapidly in the atmosphere.
IPA is not expected to persist in soil due
to its rapid evaporation, and has a low
potential to bio-accumulate in aquatic
organisms. IPA studies show low toxicity to aquatic organisms and microorganisms, and toward plant germination and growth.
Manufacturing process
IPA has been called the first petrochemical. It can be prepared via three
different methods:
Indirect hydration of propylene, using sulphuric acid and water;
Direct hydration of propylene, with
an acid catalyst; and
Catalytic hydrogenation of acetone.
This process is only suitable where
excess acetone is available and
where there is at least a $100 difference between the price for acetone
and IPA.
Indirect hydration, also
called the sulphuric-acid process, was the only method
used to produce IPA worldwide until the first commercial direct-hydration process
was introduced in 1951.
Each method has its advantages and disadvantages. For
example, direct hydration is
less corrosive than indirect
hydration mediated by sulphuric acid. However, the direct method requires a pure propylene
feed, in contrast to the indirect process, which can use a dilute, refinery
stream.
Indirect hydration of propylene
In the indirect-hydration process,
propylene is reacted with sulphuric
acid to produce mono- and diisopropylsulphates, which are then hydrolysed to
IPA.
In the two-step strong-acid pro213
Special Report
cess, separate reactors are used for
the propylene-absorption phase
and the hydrolysis of the sulphate
esters. The reaction occurs at high
sulphuric acid concentration (>80%
wt) and low temperature (e.g. 2030°C).
of 70,000-tpa at Raigad District (Maharashtra) and commenced production in
August 2006.
The weak-acid process is conducted
in a single step at lower acid concentration (60-80% wt) and higher temperature (60-65 °C).
Technological improvements in the
IPA manufacturing process caused the Direct hydration of propylene
The non-acid process,
Table 3
which is used primarily
Production & Sales of IPA
Years
Produc- Sales qty. Sales value in Europe and Japan, intion
[Tonnes]
[Rs. Mn] volves the catalytic oxidation of propylene with
[Tonnes]
water. Hydration can be
2006-07
15,886
12,552
664 gas-phase with phospho2007-08
49,447
52,239
2,549 ric acid catalyst, mixed
2008-09
51,217
51,264
2,773 phased with a cation2009-10
61,619
61,671
3,127 exchange resin, or liquid
phase using a tungsten
2010-11
67,462
67,652
4,122 catalyst. The IPA is then
purified by distillation.
strong acid process to be replaced with
the weak acid and the non-acid proIndian scenario
cesses.
In India, IPA is manufactured by
Diisopropyl ether is a significant one company, Deepak Fertilisers and
by-product of this process; it is recy- Petrochemicals Corporation Ltd. (DFcled back to the process and hydrolyzed PCL), headquartered in Pune (Maharashtra). The company put up a plant
to give the desired product.
DFPCL manufactures IPA through
the direct hydration process, producing a colourless product of high purity, with no undesirable odour or byproduct formation. The product meets
international quality standards for use
in pharmaceuticals, coatings and inks,
specialty chemicals and cosmetics. For
critical applications in the pharma sector, DFPCL has started offering IP/BP/
USP grade IPA, conforming to stringent
standards such as USP, PhEuro and IP
to name a few.
DFPCL recorded the highest ever
production of IPA at 67,462 tonnes
in 2010-2011 (production of 61,619
tonnes in 2009-10).
Trade
India has been importing as well as
exporting IPA.
Imports increased from little over
31,000-tonnes in 2005-06 to over
51,000-tonnes in 2006-07, but thereafter
with commencement of local production
declined and have been in the range of
27,000-tonnes to 35,000-tonnes.
Exports on the other hand are in
Table 4
Imports and Exports of IPA
Years
2005-06
2006-07
2007-08
2008-09
2009-10
2010-11
2011-12 (Apr-Feb)
Quantity
[Tonnes]
31,466
51,391
28,449
26,884
28,988
35,604
34,629
Imports
Value
[Rs. Mn]
1,424
2,501
1,347
1,432
1,339
2,057
2,186
CIF Value
[Rs per kg]
45.26
48.67
47.35
53.27
46.20
57.77
63.13
Quantity
[Tonnes]
–
2,627
1,920
1,605
2,288
3,975
–
Exports
Value
[Rs. Mn]
–
108
90
85
125
243
–
FOB Value
[Rs per kg]
–
41.11
46.87
52.96
54.63
61.13
–
Source: DGCIS, Kolkata and Chemical Weekly Database
214
Chemical Weekly April 24, 2012
Special Report
small; during 2010-11 they were just
3,975-tonnes valued at Rs. 61.13-mn,
but significantly point to the global acceptance of local material.
Majority of imports are sourced
from South Korea, Singapore, Taiwan,
and the US, while destination of exports
includes countries like UAE, Thailand,
Nigeria, Iran, Kenya, Egypt etc.
Consumption
The local consumption of IPA in
India in 2006-07 was 64,650-tonnes
Table 5
Top-10 suppliers of IPA into India
Country
Taiwan
USA
Korea South
Netherlands
Belgium
Singapore
Azerbaijan
China
Canada
Bahrain
Others
Total
2009-10
Quantity
Value
[Tonnes]
[Rs. Mn]
5,559
300.26
15,426
663.05
4,032
189.79
47
5.59
0
0
2,920
124.61
0
0
22
2.11
0
0.01
0
0
982
53.79
28,988
1,339.22
2010-11
Quantity
Value
[Tonnes]
[Rs. Mn]
13,523
790.86
8,169
465.73
4,282
240.68
2,808
168.63
2,475
137.34
2,429
131.78
1,199
69.77
308
24.33
130
7.13
100
5.95
182
14.67
35,604
2,056.89
Source: DGCIS
Intermediates 10%
Inks & coatings 10%
Pharma 72%
Chemical Weekly April 24, 2012
According to industry estimates,
around 72% is consumed by the
pharmaceutical industry, followed
by coatings & inks industry (10%)
and chemical intermediates (10%).
The balance (8%) is used in diverse
sectors including for agrochemicals,
thinners, metal treatment, electronics
industry etc.
As mentioned earlier, the CARG of
IPA consumption during last five years
has been around 11.5%. At a conservative growth rate of 10% in the next three
years and 8% in the subsequent two,
a demand of around 155,000-tonnes
of IPA can be projected for the year
2015-16.
With current capacity of DFPCL at
70,000-tpa, and no expansions or new
capacities announced, it is evident that
the gap of around 85,000-tonnes in supply will have to be met by imports.
Global scenario
The total global capacity for IPA is
estimated to be around 2.7-mtpa, mainly concentrated in North America, East
Asia and Europe. The United States is
the world’s largest producer, with an
annual capacity of 0.84-mtpa, accounting for about one-third of global capacity.
Others 8%
Fig. 2: Propionic acid use by application
and this has increased to around
100,000-tonnes in 2010-11, registering annual compounded growth rate of
11.5%.
In recent years accelerating development of Asian economies has
resulted in increasing production capacity in the region. The current annual production capacity of IPA in
Asia has reached nearly 0.80-mtpa.
Japan, Korea, China, India, and Taiwan are now the world’s major producers, having about one-third of the
global capacity. Capacity in Europe is
about 0.70-tpa.
215
Special Report
Table 6
Global IPA capacity by region
Region
Capacity
(tpa)
Share
(%)
USA
840,000
31
Europe
700,000
26
Asia
800,000
30
ROW
360,000
13
Total
2,700,000
100
Table 7
Global IPA consumption by region
Region
Consumption
(Tons)
Share
(%)
USA
650,000
30
Europe
500,000
23
Asia
780,000
35
ROW
270,000
12
Total
2,200,000
100
Table 8
Major IPA producers
Company
Capacity (tpa)
Shell Chemicals
480,000
Exxon Mobil
380,000
DOW Chemicals
430,000
Sasol Olefins
230,000
Deepak Fertilisers
70,000
Novapex
40,000
Lyondel Basel
30,000
Table 9
Imports of IPA by China
Years
Imports
(Tons)
2006
96,000
2007
109,800
2008
100,100
2009
102,000
2010
110,000
216
Exxon Mobil,
Dow Chemicals,
Sasol Olefins, DFPCL,
Novapex,
LyondellBasel and
Mitsui Chemicals
are some of the major producers.
local
production
satisfies 53% of demand.
US Outlook
IPA is considered a mature product
in the US, with an expected growth
rate of 1.5%/year through to 2015.
US demand is expected to reach
700,000-tonnes in 2015.
The strongest end-use markets are
in isopropylamines, household, cosmetic and personal care products, and
pharmaceuticals, growing at about
2.8%/year. These three segments collectively account for 34% of IPA demand in the US. The largest outlet for
IPA in the US is solvents, accounting
for 45% of IPA use in the country. This
sector is expected to grow modestly, by
approximately 1.2%/year, limited by
regulations covering volatile organic
compounds.
China outlook
China has a domestic IPA market of
around 230,000-tonnes in 2010, out of
which 120,000-tonnes is being met by
the local production and 110,000-tonnes
through imports. Imports thus constitute 48% of total consumption, while
Table 10
IPA demand in China by end-use:
2010
End-uses
Organic solvents
Pharmaceuticals
Chemical
intermediates
Others
Total
Demand Share
[Tonnes]
[%]
94,300
41
46,000
20
55,200
24
34,500
230,000
15
100
Major producers of IPA in China
are: Jinzhou Petrochemicals
Company (100,000-tpa capacity), Shandong Zibo Austrian Chemical Co. Ltd.
(200,000-tpa) and Haike Chemical
Group Company (30,000-tpa).
Makers of inks and coatings are the
largest consumers of IPA in China. By
2015, the use of IPA in inks and coatings will reach 127,000-tonnes, with an
average annual growth rate of 6.5%.
In 2010, the pharmaceutical industry consumed about 46,000-tonnes of
IPA. It is expected that in 2015, the
demand for IPA in the pharmaceutical
field will reach 78,000-tonnes, with an
average annual growth rate of 8%.
In 2010, about 55,200-tonnes of IPA
was used to produce organic chemicals, which figure is expected to reach
81,000-tonnes by 2015, with an average annual growth rate of 8.0%.
IPA is also used in other areas, such
as electronics, mineral flotation, dyeing/printing, household and personal
care, cosmetics and surfactants – especially in the electronics and mineral flotation industries. In 2010, demand for IPA in such areas was about
34,500-tonnes, which is expected to
reach 65,000-tonnes in 2015, at an
average growth rate of 12% per year.
By 2015, total demand for
IPA in China is expected to reach
351,000-tonnes. The domestic output is expected to go up to around
180,000-tonnes to 200,000-tonnes,
leaving a large gap of around
150,000-tonnes to 170,000-tonnes that
will have to be met through imports.
Chemical Weekly April 24, 2012