USOO81.

01560B2

(12) United States Patent (10) Patent No.: US 8,101,560 B2

(54) LUBRICANT BASE OIL OF PALM ORIGIN 5,773,391 A * 6/1998 Lawate et al. ................. 508/257
6,117,827 A 9/2000 Nagaoka et al.
(75) Inventors: Yuen May Choo, Selangor Darul Ehsan 2002/0137640 A1* 9, 2002 Memita et al. ................ 508,485
(MY); Sit Foon Cheng, Selangor Darul 2004/0014616 A1* 1/2004 Genuytet al. ................ 508,463
Ehsan (MY); Ah Ngan Ma, Selangor
Darul Ehsan (MY); Basiron Yusof, FOREIGN PATENT DOCUMENTS
Selangor Darul Ehsan (MY) GB 2264305 8, 1993
(73) Assignee: Malaysian Palm Oil Board, Selangor JP O3285988 A * 12, 1991
Darul Ehsan (MY) * cited by examiner
(*) Notice: Subject to any disclaimer, the term of this
patent is extended or adjusted under 35 Primary Examiner — Ellen McAvoy
U.S.C. 154(b) by 1049 days.
Assistant Examiner — Taiwo Oladapo
(21) Appl. No.: 10/979,782 (74) Attorney, Agent, or Firm — Muncy, Geissler, Olds &
(22) Filed: Nov. 1, 2004 Lowe, PLLC
(65) Prior Publication Data
US 2005/O119137 A1 Jun. 2, 2005 (57) ABSTRACT
(30) Foreign Application Priority Data
A cost effective and less energy demanding method of pro
Oct. 31, 2003 (MY) ............................... PI2OO34.185 ducing ester oils or lubricant base oils, particularly fatty
(51) Int. Cl. monoesters and fatty polyol esters, by esterifying palm fatty
CIOM OS/38 (2006.01) acid, which is abundant from the fat splitting process, with a
(52) U.S. Cl. ....................................................... SO8/485 monohydric alcohol or polyhydric alcohol in the presence of
(58) Field of Classification Search .................. 508/463,
an acid catalyst at elevated temperature wherein an azeotro
508/468,472, 473, 485,494; 554/174 ping agent, particularly toluene, is used to facilitate continu
See application file for complete search history. ous removal by distillation, of water formed as a by-product
during the esterification reaction. The esterification reaction
(56) References Cited is completed within 5 hours and palm fatty esters as produced
with the current method exhibit comparable lubricity and
U.S. PATENT DOCUMENTS biodegradability.
2.264,305 A 12, 1941 Gibbs
3,060,210 A * 10/1962 De Groote et al. ........... 507,244
3,071,604. A * 1/1963 Mohan et al. ................. 554f17O 7 Claims, No Drawings
 US 8,101,560 B2
1. 2
LUBRICANT BASE OL OF PALM ORIGIN raw materials with Stringent requirements are needed for the
production of the said biodegradable base oil.
RELATED APPLICATION Three most common types of synthetic oils are:
1. Poly-alpha-olefins (PAO)
This application claims priority from Malaysian Patent 2. Poly-alkylene glycols (PAG)
Application No. 20034185, filed Oct. 31, 2003, which is 3. Ester oils
incorporated by reference in its entirety. A major disadvantage of both PAOs and PAGs is their poor
solubility with regard to additives. Because the additives
FIELD OF THE INVENTION themselves must also be biodegradable, this limits the addi
10
tives that can be used to formulate effective biodegradable
This invention relates to the production of fatty esters, lubricants from PAOs and PAGs.
which are applicable as lubricant base oil. More particularly, Ester oils have acquired increasing importance as high
it relates to the production offatty esters, which are applicable quality biodegradable lubricating oils because of its high
as lubricant base oil, using palm fatty acids. 15 performance properties and custom design versatility. Ester
families commonly used in synthetic lubrication are diesters,
BACKGROUND OF THE INVENTION
polyol esters, monoesters and trimellitates. However, ester
oils are normally for high-end usage because of its higher
There are basically two types of lubricant—oil and grease. price compared to other synthetic base oils.
Oil has two components: base oil and additives. Grease has U.S. Pat. No. 5,773,391 disclosed a polyolester suitable for
three components: base oil, thickener, and additives. Note lubricant application. The polyol ester is produced by esteri
that oil and grease both share the components of base oil and fying an aliphatic or alicyclic polyol containing from 2 to
additives. The difference between an oil and grease is that about 10 hydroxyl groups with an aliphatic monocarboxylic
grease has a thickener. Additives are blended with the base oil acid mixture derived from a high oleic vegetable oil wherein
to give the oil certain properties such as corrosion resistance 25 the oleic content is at least 72 percent and the vegetable oil is
or oxidation inhibition. Generally, mineral oil has been canola oil, Sunflower oil or peanut oil. The esterification reac
employed as base oil in lubricants. tion is conducted at temperatures in the vicinity of 75° C. to
Biodegradable oils are much sought after to replace non 200°C. for 5 to about 15 or more hours. The condition needed
biodegradable mineral oils with increasing awareness of for the esterification reaction is very energy demanding as
environmental preservations. Two primary classes of biode 30
heating is needed for up to about 15 or more hours.
gradable oils are vegetable oils and synthetics. Vegetable oils
offer good biodegradability. Vegetable oils in their natural SUMMARY OF THE INVENTION
form lack sufficient oxidative stability. Low oxidative stabil
ity means, if untreated, the oil will oxidize rather quickly The current invention provides a cost effective and less
during use, becoming thick and polymerizing to a plastic-like 35
energy demanding method of producing ester oils or lubricant
consistency. Chemical modification of vegetable oils and/or base oils (herein after referred to as fatty esters), particularly
the use of antioxidants can address this problem, but increase fatty monoesters and fatty polyol esters by esterifying palm
the cost. Another negative point to vegetable oils is their high
pour point (the temperature at which oil loses fluidity and fatty acid, which is abundant from the fat splitting process,
does not flow). This problem too can be addressed by winter 40 with a monohydric alcohol or polyhydric alcohol in the pres
ization, addition of chemical additives (pour point Suppres ence of an acid catalyst at elevated temperature wherein an
sants) and/or blending with other fluids possessing lower azeotroping agent, particularly toluene, is used to facilitate
pour points, but again increase the cost. continuous removal by distillation, of water formed as a by
Despite their poor oxidative stability, vegetable oils have product during the esterification reaction. The esterification
high viscosity indices, excellent lubricity in extreme pres 45 reaction is completed within 5 hours and palm fatty esters as
sure, low volatility and good compatibility with additives. produced in the current invention exhibit comparable lubric
Palm oil which originates from Elaeis guineensis possesses ity and biodegradability minus the problem of oxidative sta
all the aforementioned advantages of a vegetable oil. In addi bility as occur by using palm olein directly as lubricant base
tion to that, palm oil has better oxidative stability compared to oil.
other vegetable oils. 50
GB patent No. 2.264.305 discloses the use of palm oil DESCRIPTION OF THE INVENTION
liquid fraction derivative, known as palm olein as the base oil
to provide a satisfactory lubricant for industrial and automo In order to provide an understanding of a number of terms
tive requirements. Although palm oil has better oxidative and phrases used in this specification and claims, the follow
stability compared to other vegetable oils, palm olein is still 55 ing definitions are provided.
not the preferred choice to be used as base oil for lubricant as The term palm fatty acid refers to saturated and non-satu
an ester additive is still needed to improve its stability and to rated fatty acids derived from palm oil and/or palm kernel oil
prevent crystallization during storage. having 8-18 carbon atoms, particularly but not exclusively
U.S. Pat. No. 6,117.827 disclosed a biodegradable base oil caprylic, capric, lauric, myristic, palmitic, Stearic, oleic,
of satisfactory low temperature fluidity, oxidative stability, 60 linoleic, linolenic acids or a mixture thereof.
lubricity and of low cloud point. The process for manufactur The term monohydric alcohol refers to those having 4-12
ing the biodegradable base oil is characterized in that hard carbonatoms, particularly but not exclusively butanol, ethyl
ened palm fractionated oil, high oleic Sunflower oil and hexanol and their isomers.
medium chain triglyceride are mixed and Subjected simulta The term polyhydric alcohol refers to those having 4-8
neously to an ester interchange reaction in the presence of an 65 carbonatoms, particularly but not exclusively neopentylgly
enzymatic catalyst, wherein the enzymatic catalyst is a lipase cols, trimethylol propane, pentaerythritol, ethylene glycol
having a specificity to glyceride positions 1 and 3. Multiple and diethyl propanediol.
 US 8,101,560 B2
3 4
The term Bronstead or Lewis acid catalyst refers to con mixture is condensed at the separating funnel, it separates into
centrated Sulfuric acid, p-toluene Sulfonic acid and acidic ion two layers wherein the bottom layer is water and the top layer
exchange resin. is an organic phase. The bottom layer of water collected at the
The term drying agent refers to a substance which is separating funnel is drained from time to time. At a time
capable of removing water and applicable foresters, particu during the reaction, the organic phase would overflow and
larly anhydrous sodium Sulphate. recycle back to the reaction mixture. This is an important
The term azeotroping agent refers to a compound which is aspect as to ensure a Substantial amount of toluene is present
capable of forming an azeotrope mixture with water, particu in the reaction mixture in order to form an azeotrope mixture
with water.
larly toluene.
The term reactant refers to palm fatty acid, monohydric 10 Excess solvent is removed from the palm fatty esters pro
alcohol, polyhydric alcohol or a mixture thereof. duced by means of rotary evaporation and then homogeneous
The term palm fatty ester refers to fatty monoester or fatty acid catalyst is removed by repeated washing with water.
After that, the palm fatty ester produced is dried with a drying
polyol ester obtained from esterification of palm fatty acid. agent and underwent further purification to remove excess
The term solvent refers to Volatile azeotroping agent and 15 palm fatty acid, impurities and trace solvent. The step of acid
eXceSS reactant. catalyst removal is simplified if heterogeneous acid catalyst is
The fatty monoesters of the present invention are prepared used as it can be removed by simple filtration.
by esterification of palm fatty acid with monohydric alcohol The preferred embodiment of the present invention is as
wherein the monohydric alcohol is present in molar excess of written below:
palm fatty acid (not less than 1 mole of monohydric alcohol Production of Fatty Monoesters as Lubricant Base Oil
per 1 mole of palm fatty acid). A Stoikiometric mixture of palm fatty acid and monohydric
alcohol is transferred into a reaction flask. A molar excess of
Palm Fatty + Monohydric were Fatty + Water
monohydric alcohol is then added to the reaction mixture.
Then, the reaction flask is equipped with a modified Dean and
Acid Alcohol Monoesters
25 Stark distillation set-up, magnetic stirrer, condenser, drop
ping funnel and heating plate. An amount of toluene is added
to the reaction mixture. Later, a catalytic amount of acid
The fatty polyolesters of the present invention are prepared catalyst is added slowly to the reaction mixture when it has
by esterification of palm fatty acid with polyhydric alcohol reached the temperature in the vicinity of 80° C. to 150° C.
wherein the palm fatty acid is present in molar excess of 30 Heating continued for not more than 5 hours. Water formed as
polyhydric alcohol (not less than 2 moles of palm fatty acid by-product of the esterification reaction is removed continu
per 1 mole of polyhydric alcohol). ously by means of distillation with the aid of toluene while
toluene is recycled continuously back to the reaction mixture.
After the reaction is completed, the crude product is cooled
Palm Fatty + Monohydric ar Fatty + Water 35 to ambient temperature. Then, excess Solvent is removed
Acid Alcohol Polyol Esters
from the crude product by means of rotary evaporation. If
homogeneous acid catalyst is utilized in the esterification
reaction, it is removed by repeated washing with water until
Excess reactant is used to aid the completion of esterifica the product produced is neutral. After that, the product is dried
tion reaction. In the present invention, a molar excess of 40 with anhydrous Sodium Sulphate and the hydrated Sodium
monohydric alcohol is used in the preparation of fatty sulphate is later removed from the dried product. The dried
monoesters whereas a molar excess of palm fatty acid is used product is further purified by using a column packed with
in the preparation of fatty polyol esters. The different choice silica gel. Trace solvent is further removed by a vacuum pump
of excess reactant, besides governed by the Stoikiometric and finally unreacted palm fatty acid is removed by means of
equation of the reaction, is mainly influenced by the boiling 45 vacuum distillation. Unreacted palm fatty acid would remain
point of the particular reactant since excess reactant needs to as residue while fatty monoester would be collected as distil
be removed totally after the reaction. Thus, normally the more late. The step of acid catalyst removal is simplified if hetero
easily remove reactant would be in excess. geneous acid catalyst is used as it can be removed by simple
The esterification reaction can be conducted at a relatively filtration and no washing required.
moderate temperature and yet achieve high conversion rates 50 Production of Polyol Esters as Lubricant Base Oil
over short reaction time by the use of an azeotroping agent to A Stoikiometric mixture of palm fatty acid and polyhydric
assist the removal of water formed as a by-product of the alcohol is transferred into a reaction flask. Two molar excess
reaction, thus drive the reaction to completion. offatty acid are then added to the reaction mixture. Then, the
The esterification reaction is effected utilizing a Bronstead reaction flask is equipped with a modified Dean and Stark
or Lewis acid catalyst attemperatures in the vicinity of 80°C. 55 distillation set-up, magnetic stirrer, condenser, dropping fun
to 210°C., more particularly in the vicinity of 80° C. to 150° nel and heating plate. An amount of toluene is added to the
C. for production of fatty monoesters and in the vicinity of reaction mixture. Later, a catalytic amount of acid catalyst is
120° C. to 210°C. for production of fatty polyol esters. The added slowly to the reaction mixture when it has reached the
esterification reaction is complete in not more than 5 hours. temperature in the vicinity of 120° C. to 210° C. Heating
The preferred azeotroping agent is toluene. Addition of 60 continued for not more than 5 hours. Water formed as by
aforementioned azeotroping agent helps to facilitate the product of the esterification reaction is removed continuously
removal of water from the reaction mixture by distillation. by means of distillation with the aid of toluene while toluene
The water is removed in the form of a binary mixture (water is recycled continuously back to the reaction mixture.
and toluene) and/or ternary mixture (water, alcohol and tolu After the reaction is completed, the crude product is cooled
ene). Addition of toluene helps the removal of water since the 65 to ambient temperature. Then, excess Solvent is removed
boiling point of the azeotrope mixture (85°C.) is lower than from the crude product by means of rotary evaporation. If
the boiling point of water (100° C.). When the azeotrope homogeneous acid catalyst is utilized in the esterification
 US 8,101,560 B2
5 6
reaction, it is removed by repeated washing with water until added to the reaction mixture when it has reached the tem
the product produced is neutral. After that, the product is dried perature of 160° C. Heating continued for not more than 5
with anhydrous sodium Sulphate and the hydrated sodium hours. Water formed as by-product of the esterification reac
sulphate is later removed from the dried product. The dried tion is removed continuously by means of distillation with the
product is further purified by using a column packed with 5 aid of toluene while toluene is recycled continuously back to
silica gel. Trace solvent is further removed by a vacuum pump the reaction mixture.
and finally unreacted palm fatty acid is removed by means of After the reaction is completed, the crude product is cooled
vacuum distillation. Unreacted palm fatty acid would remain to ambient temperature. Then, excess Solvent is removed
as residue while fatty polyol ester would be collected as from the crude product by means of rotary evaporation. Sul
distillate. The step of acid catalyst removal is simplified if phuric acid is removed by repeated washing with water until
heterogeneous acid catalyst is used as it can be removed by the product produced is neutral. After that, the product is dried
simple filtration and no washing required. with anhydrous Sodium Sulphate and the hydrated Sodium
The following examples are presented for the purpose of sulphate is later-removed from the dried product. The dried
illustration only, and not intended to be construed in a limiting product is further purified by using a column packed with
SSC. 15 silica gel. Trace solvent is further removed by a vacuum pump
and finally unreacted palm fatty acid is removed by means of
Example 1 vacuum distillation. Unreacted palm fatty acid would remain
as residue while pentaerythritol ester would be collected as
Production of Butyl Ester as Lubricant Base Oil distillate.
2O
A reaction mixture of 1 mole of palm fatty acid and 3 moles Example 4
of butanol is transferred into a reaction flask. The reaction
flask is equipped with a modified Dean and Stark distillation Production of Neopentyl Glycol Ester as Lubricant
set-up, magnetic stirrer, condenser, dropping funnel and heat Base Oil
ing plate. 1 mole of toluene is added to the reaction mixture. 25
1 weight percent of Sulphuric acid (based on weight of Sul A reaction mixture of 3 moles of palm fatty acid and 1 mole
phuric acid/weight of palm fatty acid used) is added to the of neopentylglycol is transferred into a reaction flask. The
reaction mixture when it has reached the temperature of 120° reaction flask is equipped with a modified Dean and Stark
C. Heating continued for not more than 5 hours. Waterformed distillation set-up, magnetic stirrer, condenser, dropping fun
as by-product of the esterification reaction is removed con- 30 nel and heating plate. 1 mole of toluene is added to the
tinuously by means of distillation with the aid of toluene reaction mixture. 1 weight percent of Sulphuric acid (based on
while toluene is recycled continuously back to the reaction weight of sulphuric acid/weight of palm fatty acid used) is
mixture. added to the reaction mixture when it has reached the tem
After the reaction is completed, the crude product is cooled perature of 160° C. Heating continued for not more than 5
to ambient temperature. Then, excess solvent is removed 35 hours. Water formed as by-product of the esterification reac
from the crude product by means of rotary evaporation. Sul tion is removed continuously by means of distillation with the
phuric acid is removed by repeated washing with water until aid of toluene while toluene is recycled continuously back to
the product produced is neutral. After that, the product is dried the reaction mixture.
with anhydrous sodium Sulphate and the hydrated sodium After the reaction is completed, the crude product is cooled
sulphate is later removed from the dried product. The dried 40 to ambient temperature. Then, excess Solvent is removed
product is further purified by using a column packed with from the crude product by means of rotary evaporation. Sul
silica gel. Trace solvent is further removed by a vacuum pump phuric acid is removed by repeated washing with water until
and finally unreacted palm fatty acid is removed by means of the product produced is neutral. After that, the product is dried
vacuum distillation. Unreacted palm fatty acid would remain with anhydrous Sodium Sulphate and the hydrated Sodium
as residue while butyl ester would be collected as distillate. 45 sulphate is later removed from the dried product. The dried
product is further purified by using a column packed with
Example 2 silica gel. Trace solvent is further removed by a vacuum pump
and finally unreacted palm fatty acid is removed by means of
Production of 2-Ethylhexyl Ester as Lubricant Base vacuum distillation. Unreacted palm fatty acid would remain
Oil 50 as residue while neopentylglycol ester would be collected as
distillate.
2-ethylhexyl ester is produced by substituting butanol with
2-ethylhexanol in Example 1 and 2-ethylhexyl ester instead Example 5
of butyl ester is collected as distillate in the final step.
55 Production of Trimethylol Propane Ester as
Example 3 Lubricant Base Oil

Production of Pentaerythritol Ester as Lubricant A reaction mixture of 4 moles of palm fatty acid and 1 mole
Base Oil of trimethylol propane is transferred into a reaction flask. The
60 reaction flask is equipped with a modified Dean and Stark
A reaction mixture of 5 moles of palm fatty acid and 2 distillation set-up, magnetic stirrer, condenser, dropping fun
moles of pentaerythritol is transferred into a reaction flask. nel and heating plate. 1 mole of toluene is added to the
The reaction flask is equipped with a modified Dean and Stark reaction mixture. 1 weight percent of Sulphuric acid (based on
distillation set-up, magnetic stirrer, condenser, dropping fun weight of Sulphuric acid/weight of palm fatty acid used) is
nel and heating plate. 1 mole of toluene is added to the 65 added to the reaction mixture when it has reached the tem
reaction mixture. 1 weight percent of Sulphuric acid (based on perature of 160° C. Heating continued for not more than 5
weight of Sulphuric acid/weight of palm fatty acid used) is hours. Water formed as by-product of the esterification reac
 US 8,101,560 B2
7 8
tion is removed continuously by means of distillation with the TABLE 1-continued
aid of toluene while toluene is recycled continuously back to
the reaction mixture. Viscosity at 40° C. and 100° C. for Fatty Monoesters
After the reaction is completed, the crude product is cooled Fatty Viscosity (cSt
to ambient temperature. Then, excess solvent is removed 5
from the crude product by means of rotary evaporation. Sul Monoester 40° C. 100° C.
phuric acid is removed by repeated washing with water until 2-Butyl Oleate 6.56 2.22
the product produced is neutral. After that, the product is dried 2-Butyl Stearate 7.34 2.48
with anhydrous sodium Sulphate and the hydrated sodium 2-Ethylhexyl Palmitate 7.98 2.53
10 2-Ethylhexyl Stearate 7.71 2.22
sulphate is later removed from the dried product. The dried n-Butyl Palmitate & n-Butyl Stearate 6.39 2.23
product is further purified by using a column packed with n-Octyl Oleate 9.11 2.87
silica gel. Trace solvent is further removed by a vacuum pump Oleyl Caprylate 10.34 3.16
and finally unreacted palm fatty acid is removed by means of
vacuum distillation. Unreacted palm fatty acid would remain 15
as residue while trimethylol propane ester would be collected TABLE 2
as distillate.
Viscosity at 40° C. and 100° C. for Fatty Polyol Esters
Example 6 Fatty Viscosity (cSt
Production of n-Butyl Palmitate as Lubricant Base Polyol Ester 40° C. 100° C.
Oil
Neopentylglycol Dicaprylate 7.18 2.34
Neopentylglycol Dicaprate 10.2O 2.73
A reaction mixture of 1 mole of palmitate acid and 3 moles Neopentylglycol Dilaurate 15.58 4.21
of n-butanol is transferred into a reaction flask. The reaction Neopentylglycol Dioleate 26.90 6.69
25
flask is equipped with a modified Dean and Stark distillation Pentaerythritol Tetracaprylate
Pentaerythritol Tetracaprate
21.84
23.49
4.41
4.33
set-up, magnetic stirrer, condenser, dropping funnel and heat Trimethylolpropane Tricaprylate 20.96 4.96
ing plate. 1 mole of toluene is added to the reaction mixture. Trimethylolpropane Tricaprate 22.45 4.14
40 weight percent of acidic ion exchange resin (based on TrimethylolpropaneTrioleate 40.95 8.85
weight of acidic ion exchange resin/weight of palm fatty acid Diethyleneglycol Dioleate 21.45 5.50
30 Diethylpropanedioyl Dioleate 31.47 6.88
used) is added to the reaction mixture when it has reached the Ethyleneglycol Dioleate 18.62 4.99
temperature 120° C. Concentration of active sites for the
acidic ion exchange resins used is not less than 1.7 equiva
lents per litre or not less than 4.7 equivalents per kilogram.
Heating continued for not more than 5 hours. Water formed as Example 8
35
by-product of the esterification reaction is removed continu
ously by means of distillation with the aid of toluene while Viscosity index for palm fatty esters as produced by using
toluene is recycled continuously back to the reaction mixture. method of the present invention is shown below. The viscosity
After the reaction is completed, the crude product is cooled indices are determined according to ASTM D2270.
to ambient temperature. Then, excess solvent is removed 40
from the crude product by means of rotary evaporation. The TABLE 3
product is dried with anhydrous Sodium Sulphate and the Viscosity Index for Fatty Monoesters
hydrated sodium sulphate is later removed from the dried
product along with acidic ion exchange resin. The dried prod Fatty Monoester Viscosity Index
uct is further purified by using a column packed with silica
gel. Trace solvent is further removed by a vacuum pump and 45 n-Butyl Palmitate 196
n-Butyl Oleate 2O7
finally unreacted palmitate acid is removed by means of n-Butyl Stearate 199
vacuum distillation. Unreacted palmitate acid would remain 2-Butyl Palmitate 2O3
as residue while n-butyl ester would be collected as distillate. 2-Butyl Oleate 186
2-Butyl Stearate 167
Example 7 50 2-Ethylhexyl Palmitate 161
2-Ethylhexyl Stearate 190
n-Octyl Oleate 185
Viscosity at 40° C. and 100° C. for palm fatty esters as Oleyl Caprylate 189
produced by using method of the present invention are shown
below. The viscosities are determined according to ASTM
D445. 55
TABLE 4
TABLE 1. Viscosity Index for Fatty Polyol Esters
Viscosity at 40° C. and 100° C. for Fatty Monoesters Fatty Polyol Ester Viscosity Index
60
Fatty Viscosity (cSt Neopentylglycol Dicaprylate 119
Neopentylglycol Dicaprate 140
Monoester 40° C. 100° C. Neopentylglycol Dilaurate 147
Neopentylglycol Dioleate 210
n-Butyl Palmitate 5.58 2.04 Pentaerythritol Tetracaprylate 123
n-Butyl Oleate 6.OO 2.17 Pentaerythritol Tetracaprate 156
n-Butyl Stearate 7.17 2.45 65 Trimethylolpropane Tricaprylate 156
2-Butyl Palmitate 5.73 2.09 Trimethylolpropane Tricaprate 187
 US 8,101,560 B2
9 10
TABLE 4-continued TABLE 7-continued
Viscosity Index for Fatty Polyol Esters Water Separability for Fatty Monoesters
Fatty Polyol Ester Viscosity Index Fatty Monoester Water Separability (minutes)
TrimethylolpropaneTrioleate 190 2-Butyl Stearate
Diethyleneglycol Dioleate 214 2-Ethylhexyl Palmitate 2
Diethylpropanedioyl Dioleate 188 2-Ethylhexyl Stearate
Ethyleneglycol Dioleate 216 n-Butyl Palmitate & n-Butyl Stearate
n-Octyl Oleate
10 Oleyl Caprylate
Example 9
TABLE 8
Flash point for palm fatty esters as produced by using Water Separability for Fatty Polyol Esters
method of the present invention is shown below. The flash 15
points are determined according to ASTM D93. Fatty Polyol Ester Water Separability (minutes)
Neopentylglycol Dicaprylate 13
TABLE 5 Neopentylglycol Dicaprate 17
Neopentylglycol Dilaurate 27
Flash Point for Fatty Monoesters Neopentylglycol Dioleate 10
Pentaerythritol Tetracaprylate 21
Fatty Monoester Flash Point (C.) Pentaerythritol Tetracaprate 18
Trimethylolpropane Tricaprylate 27
n-Butyl Palmitate 160 Trimethylolpropane Tricaprate 10
n-Butyl Oleate 210 TrimethylolpropaneTrioleate 2O
n-Butyl Stearate 218 Diethyleneglycol Dioleate 8
2-Butyl Palmitate 186 25
Diethylpropanedioyl Dioleate 8
2-Butyl Oleate 176 Ethyleneglycol Dioleate 11
2-Butyl Stearate 198
2-Ethylhexyl Palmitate 140
2-Ethylhexyl Stearate 120
n-Butyl Palmitate & n-Butyl Stearate 2O2 Example 11
n-Octyl Oleate 178 30
Oleyl Caprylate 190 Moisture content for palm fatty esters as produced by using
method of the present invention is shown below. The moisture
contents are determined according to ASTM E1064.
TABLE 6
35 TABLE 9
Flash Point for Fatty Polyol Esters
Moisture Content for Fatty Monoesters
Fatty Polyol Ester Flash Point (C.)
Fatty Monoester Moisture Content (ppm)
Neopentylglycol Dicaprylate 195
Neopentylglycol Dicaprate 175 40 n-Butyl Palmitate 195
Neopentylglycol Dilaurate 178 n-Butyl Oleate 530
Neopentylglycol Dioleate 230 n-Butyl Stearate 442
Pentaerythritol Tetracaprylate 160 2-Butyl Palmitate S4
Pentaerythritol Tetracaprate 150 2-Butyl Oleate 94
Trimethylolpropane Tricaprylate 168 2-Butyl Stearate 167
Trimethylolpropane Tricaprate 184 2-Ethylhexyl Palmitate 81
TrimethylolpropaneTrioleate 124 45 2-Ethylhexyl Stearate 711
Diethyleneglycol Dioleate 170 n-Butyl Palmitate & n-Butyl Stearate 517
Diethylpropanedioyl Dioleate 240 n-Octyl Oleate 129
Ethyleneglycol Dioleate 140 Oleyl Caprylate 72

50
Example 10 TABLE 10

Water separability at 54° C. for palm fatty esters as pro Moisture Content for Fatty Polyol Esters
duced by using method of the present invention is shown Fatty Polyol Ester Moisture Content (ppm)
below. The water separabilities are determined according to 55
ASTM D892. Neopentylglycol Dicaprylate 140
Neopentylglycol Dicaprate 112
Neopentylglycol Dilaurate 98
TABLE 7 Neopentylglycol Dioleate 64
Pentaerythritol Tetracaprylate 89
Water Separability for Fatty Monoesters 60 Pentaerythritol Tetracaprate 87
Trimethylolpropane Tricaprylate 98
Fatty Monoester Water Separability (minutes) Trimethylolpropane Tricaprate 154
TrimethylolpropaneTrioleate 105
n-Butyl Palmitate Diethyleneglycol Dioleate 55
n-Butyl Oleate Diethylpropanedioyl Dioleate 47
n-Butyl Stearate Ethyleneglycol Dioleate 106
2-Butyl Palmitate 3 65
2-Butyl Oleate
 US 8,101,560 B2
11 12
What is claimed is: 0.5 to 1.0 weight percent based on weight of the acid men
1. A process of producing lubricant base oil consisting of tioned per weight of the palm fatty acid used.
the steps of 6. The process of claim 1 wherein the acidic ion-exchange
a) esterifying oleic acid with a polyhydric alcohol selected resin is present in an amount of 40 weight percent based on
from diethyl propanediol in the presence of an acid weight of the resin mentioned per weight of the palm fatty
acid used.
catalyst selected from Sulfuric acid, p-toluene Sulfonic 7. A process of producing lubricant base oil consisting of
acid and acidic ion exchange resin at elevated tempera the steps of
ture to yield diethylpropanedioyl dioleate, (i) esterifying oleic acid with a polyhydric alcohol selected
b) continuously removing water formed as a by-product 10 from diethyl propanediol in the presence of an acid
during the reaction in (a) by distillation, catalyst selected from Sulfuric acid, p-toluene Sulfonic
c) removing the acid catalyst, impurities, and solvent from acid and acidic ion exchange resinata temperature in the
the resultant product of step (a) and (b), and vicinity of 120° C. to 210° C. for less than 5 hours
d) in step (b) adding an azeotroping agent to facilitate wherein not less than 2 moles of palm fatty acid are
continuous removal of water to yield a lubricant base oil, 15 present per mole of polyhydric alcohol used to yield
wherein the moisture content of the lubricant base oil is diethylpropanedioyl dioleate,
not more than 600 ppm, and the water separability of the (ii) using toluene to facilitate continuous removal by dis
lubricant base oil is not more than 30 minutes. tillation, of water formed as a by-product during the
2. The process of claim 1 wherein the azeotroping agent is esterification reaction,
toluene. (iii) purifying the product obtained from (ii) by removing
3. The process of claim 1 wherein the elevated temperature acid catalyst, solvent, and impurities to yield a lubricant
is in the vicinity of 80° C. to 210°C. base oil, wherein the moisture content of the lubricant
4. The process of claim 1 wherein the elevated temperature base oil is not more than 600 ppm, and the water sepa
is in the vicinity of 120° C. to 210°C. rability of the lubricant base oil is not more than 30
minutes.
5. The process of claim 1 wherein the concentrated sulphu 25
ric acid or p-toluene Sulphonic acid is present in an amount of