Listing description
Castor oil is a vegetable oil obtained by pressing the seeds of the castor oil plant (Ricinus communis).[1] The common name "castor oil", from
which the plant gets its name, probably comes from its use as a replacement for castoreum, a perfume base made from the driedperineal glands of the beaver (castor in Latin).
Detailed description
Castor oil is a colorless to
very pale yellow liquid with a distinct taste and odor once first ingested. Its boiling
point is
313 °C (595 °F) and itsdensity is 961 kg/m3.[3] It is a triglyceride in which approximately 90 percent of fatty
acid chains are ricinoleate. Oleate and linoleates are
the other significant components.
Castor oil and its derivatives
are used in the manufacturing of soaps, lubricants,
hydraulic and brake
fluids, paints, dyes, coatings, inks, cold
resistant plastics, waxes and polishes, nylon, pharmaceuticals and perfumes.[4]
Composition
Castor oil is well known as a
source of ricinoleic acid, a monounsaturated,
18-carbon fatty
acid. Among fatty acids, ricinoleic acid is unusual in that it has a hydroxyl functional
group on the
12th carbon. This functional group causes ricinoleic acid (and castor oil) to
be more polarthan most fats. The chemical reactivity of the
alcohol group also allows chemical derivatization that
is not possible with most other seed oils. Because of its ricinoleic acid
content, castor oil is a valuable chemical in feedstocks, commanding a higher
price than other seed oils. As an example, in July 2007, Indian castor oil sold
for about US$0.90 per kilogram (US$0.41 per pound)[5] whereas U.S. soybean, sunflowerand canola oilseeds sold for about US$0.30 per
kilogram (US$0.14 per pound).[6]
|
Acid name
|
Average
Percentage Range
|
|
85 –
95%
|
|
|
2 –
6%
|
|
|
1 –
5%
|
|
|
0.5 –
1%
|
|
|
0.5 –
1%
|
|
|
0.5 –
1%
|
|
|
0.3 –
0.5%
|
|
|
Others
|
0.2 –
0.5%
|
Uses
Annually 270,000–360,000 tonnes
(600–800 million pounds) of castor oil are produced for a variety of uses.[4]
Food and preservative
In the food industry, castor
oil (food grade) is used in food additives, flavorings, candy (e.g., polyglycerol
polyricinoleate or
PGPR in chocolate),[7] as
a mold inhibitor, and in packaging. Polyoxyethylated castor oil (e.g., Kolliphor EL)[8] is
also used in the food industries.[9]
In India, Pakistan, Nepal and
Bangladesh, food grains are preserved by applying castor oil. It stops rice,
wheat, and pulses from rotting. For example, the legume pigeon
pea is
commonly available coated in oil for extended storage.
Medicine
The United States Food and Drug Administration (FDA) has categorized castor oil as "generally recognized as
safe and effective" (GRASE) for over-the-counter use as a laxativewith its major site of action the small
intestine where
it is digested into ricinoleic acid.[10] Despite castor oil being widely used to
induce labor in pregnant women, to date there is not enough research to show
whether it is effective to ripen the cervix or induce labor.[11] Therapeutically, modern drugs are rarely
given in a pure chemical state, so most active ingredients are combined with excipients or
additives. Castor oil, or a castor oil derivative such as Kolliphor EL (polyethoxylated
castor oil, a nonionic surfactant), is
added to many modern drugs, including:
·
Sandimmune (cyclosporine injection, USP), an immunosuppressant drug
widely used in connection with organ transplant to reduce the activity of the
patient's immune system;[15]
·
Tacrolimus, an
immunosuppressive drug (contains HCO-60, polyoxyl 60 hydrogenated
castor oil);[citation needed]
·
Xenaderm ointment, a topical treatment for skin ulcers, is a
combination of Balsam
of Peru, castor oil, and trypsin;[17][18]
·
Aci-Jel (composed of ricinoleic acid from castor oil, with acetic
acid and oxyquinoline) is used to maintain the acidity
of the vagina.[19]
Alternative medicinal use
In naturopathy castor oil has been promoted as a treatment
for a variety of human health conditions,[20] including
cysts.[21] The claim has been made that applying it to
the skin can help cure cancer. However, according to the American Cancer Society, "available scientific
evidence does not support claims that castor oil on the skin cures cancer or
any other disease."[22]
Coatings
Castor oil is used as bio-based polyol in
the polyurethane industry. The average functionality (number
of hydroxyl groups per triglyceride molecule) of castor
oil is 2.7, so it is widely used as rigid polyol and coating.[1]
Castor oil is not a drying
oil, meaning that it has a low reactivity toward air compared to
say linseed
oil and tung oil. Dehydration of castor oil gives linoleic acids, which does have drying properties.[1]
Precursor to industrial chemicals
Castor oil can be broken down
into other chemical compounds that have numerous applications.[23][24][25] Transesterification followed by steam
cracking gives undecylenic acid, a precursor to specialized polymer nylon 11, and heptanal, a component in fragrances.[26] Break down of castor oil in strong base
gives 2-octanol, both
a fragrance component and a specialized solvent, and the dicarboxylic acid sebacic acid. Hydrogenation of castor oil saturates
the alkenes, giving a waxy lubricant.[1]
The production of lithium
grease consumes
a significant amount of castor oil. Hydrogenation and saponification of
castor oil yields 12-hydroxystearic acid which is then reacted with lithium
hydroxide or lithium
carbonate to give
high performance lubricant grease.[27]
Since it has a relatively high dielectric constant (4.7),
highly refined and dried castor oil is sometimes used as a dielectric
fluid within
high performance high voltage capacitors.
Lubrication
Vegetable oils like castor oil
are typically unattractive alternatives to petroleum-derived lubricants because of their poor oxidative stability.[28][29] Castor oil has better low temperature viscosity properties and high temperature lubrication
than most vegetable oils, making it useful as a lubricant in jet, diesel, and
racing engines.[30] The viscosity of castor oil at 10 °C
is 2,420 centipoise.[31] However, castor oil tends to form gums in a short time, and therefore its
usefulness is limited to engines that are regularly rebuilt, such as racing
engines. The lubricants company Castrol took its name from castor oil.
Castor oil has been suggested
as a lubricant for bicycle
pumps because
it does not degrade natural rubber seals.[32]
Early aviation and aeromodelling
Castor oil was the preferred lubricant for rotary
engines, such as the Gnome
engine after
that engine's widespread adoption for aviation in Europe in 1909. It was used
almost universally in rotary engined Allied aircraft in World War
I. Germany had to make do with inferior ersatz oil for its rotary engines, which resulted
in poor reliability.[33][34][35]
The methanol-fueled
two-cycle glow plug engines used for aeromodelling, since their
adoption by model
airplane hobbyists
in 1948, have used varying percentages of castor oil as a lubricant. It is
highly resistant to degradation when the engine has its fuel-air mixture leaned
for maximum engine speed. Gummy residues can still be a problem for
aeromodelling powerplants lubricated with castor oil, however, usually
requiring eventual replacement of ball
bearings when
the residue accumulates within the engine's bearing races. One British
manufacturer of sleeve
valved four-cycle
model engines has stated the "varnish" created by using castor oil in
small percentages can improve the pneumatic seal of the sleeve valve, improving
such an engine's performance over time.
Turkey red oil
Turkey red oil, also called
sulphonated (or sulfated) castor oil, is made by adding sulfuric acid to
vegetable oils, most notably castor oil.[36] It was the first synthetic detergent after ordinary soap. It is
used in formulating lubricants,
softeners, and dyeing assistants.[37]
Biodiesel
Castor oil, like currently less
expensive vegetable oils, can be used as feedstock in the production of biodiesel. The
resulting fuel is superior for cold winters, due to its exceptionally low cloud and pour
points.[38]
Initiatives to grow more castor
for energy production, in preference to other oil crops, are motivated by
social considerations. Tropical subsistence farmers would gain a cash crop.[39]
Punishment
Parents often punished children
with a dose of castor oil.[40][41] Physicians recommended against the practice
because they did not want medicines associated with punishment.[42]
A heavy dose of castor oil
could be used as a humiliating punishment for adults, especially political
dissenters. Colonial officials used it in the British
Raj (India)
to deal with recalcitrant servants.[43]
The most famous use as
punishment came in Fascist
Italy under Benito
Mussolini. It was a favorite tool used by the Blackshirts to
humiliate their opponents.[44][45][46] Political dissidents were force-fed large quantities of castor
oil by Fascist squads. This technique was said to have been originated by Gabriele D'Annunzio. Victims of this treatment did
sometimes die, as the dehydrating effects of the oil-induced diarrhea often
complicated the recovery from the nightstick beating they also received along
with the castor oil; however, even those victims who survived had to bear the
humiliation of the laxative effects resulting from excessive consumption of the
oil.[47]
It is said Mussolini's power
was backed by "the bludgeon and castor oil". In lesser quantities,
castor oil was also used as an instrument of intimidation, for example, to
discourage civilians or soldiers who would call in sick either in the factory
or in the military. It
took decades after Mussolini's death before the myth of castor oil as a panacea
for a wide range of diseases and medical conditions was totally demystified, as
it was also widely administered to pregnant women, elderly or mentally-ill
patients in hospitals in the false belief it had no negative side effects.
Today, the Italian terms manganello and olio
di ricino, even used separately, still carry strong political connotations
(especially the latter). These words are still used to satirize patronizing
politicians, or the authors of disliked legislation. They should be used with
caution in common conversation. The terms Usare
l'olio di ricino, ("to use castor oil") andusare il manganello ("to use the bludgeon") mean
"to coerce or abuse", and can be misunderstood in the absence of
proper context.
As a means of punishment or
torture, force-feeding castor oil still lives on in animated cartoons such as Tom and Jerry.
Safety
The castor seed contains ricin,
a toxic protein. Heating during the oil extraction process denatures and
deactivates the protein. However, harvesting castor beans may not be without
risk.[48] Allergenic compounds found on the plant surface can
cause permanent nerve damage, making the harvest of castor beans a human health
risk. India, Brazil, and China are the major crop producers, and the workers
suffer harmful side effects from working with these plants.[49] These health issues, in addition to
concerns about the toxic byproduct (ricin) from castor oil production, have
encouraged the quest for alternative sources for hydroxy fatty acids. Alternatively, some researchers are trying
to genetically modify the castor plant to prevent the synthesis of ricin.[52]
While castor oil is sometimes
used to induce full-term pregnancies (scientific evidence of its effectiveness
is lacking),[53] consuming castor oil to treat constipation
is not considered safe in pregnancies that are not at full term yet, since it
may cause contractions of the womb
PRICE
$30.03/KG
For more information:
mobile: +2348039721941
contact person: emeaba uche
website: www.franchiseminerals.com
e-mail: emeabau@yahoo.com
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