Note: Descriptions are shown in the official language in which they were submitted.
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A PROCESS FOR CONVERSION OF LOW COST AND HIGH FFA OILS TO
BIODIESEL
FIELD OF INVENTION
The present invention relates to a process for conversion of low cost and high
free fatty
acid (FFA) oils to biodiesel. The present invention particularly relates to a
process of
converting high FFA containing feed stocks (FFA 20-85 %) to biodiesel in the
presence
of macro reticular and gel type acidic heterogeneous resin followed by
transesterification in presence of homogeneous basic catalyst and separation
of
biodiesel and glycerine.
BACKGROUND OF THE INVENTION
Vegetable oil or fat is generally obtained by extraction or pressing natural
seeds.
Vegetable oil usually contains free fatty acids, phospholipids, sterols,
water,
tocopherols and other impurities. While as Palm fatty acid distillate (PFAD),
Soya
deodistillate, acid oil, are obtained as byproducts during refining of Palm
oil or soya
oil. These oils are mainly low cost material containing FFA in the range of 20-
85%,
while as restaurant grease is the waste oil collecting in grease traps from
Kitchens of
hotels and restaurants.
Vegetable seed oils have about 90% of the heat content of petroleum based
diesel fuel
and a favorable energy output/input ratio and, therefore, have the potential
to replace
congenital diesel fuel for compression ignition engines.
The vegetable oils have another advantage as these have high cetane number up
to 50.
Added advantage of -10 Cetane number is further obtained when vegetable oils
are
converted to methyl/ethyl monoesters. Thus these esters, with viscosity,
boiling point
and heat values in the range of diesel fuel and higher cetane number, have an
advantage
over the use of vegetable oils as such Therefore, these can be used as high
cetane
number blending components to the diesel fuel.
The most common catalysts used for transesterification of vegetable oils to
produce
biodiesel include alkali, acids and enzymes. The alkali includes NaOH, KOH,
sodium
and potassium alkoxides such as sodium methoxide, potassium methoxide.
Generally
used acid catalysts are sulfuric acid, phosphoric acid, hydrochloric acid and
sulfonic
acids. Among the biocatalyst lipase can be used for transesterification. With
alkaline
CONFIRMATION COPY
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catalysts, the free fatty acid and water contents in the oil or fats
significantly affect the
transesterification by deactivating the catalyst and interfering with the
separation of
fatty acid esters and glycerol and for acidic catalyst e.g. H2S04 large
quantity of alkali
is used to neutralize the mineral acids and hence the disposal problems.
Reference may be made to Patent No. W09115452 where in, they described fatty
acid
alkyl esters are produced by catalytic transesterification of a vegetable oil
using
alkaline earth metal calcium, (Ca), or compounds thereof, at normal
atmospheric
pressure and normal room temperature below 50 C,
Reference may be made to CA Patent No. 2,316,141 where in, they described a
process
comprises forming a single phase solution of said triglyceride in an alcohol
selected
from methanol and ethanol, the ratio of alcohol to triglyceride being 15:1 to
35:1. The
solution further comprises a co-solvent in an amount to effect formation of a
single
phase and a base catalyst for the esterification reaction. After a period of
time, ester is
recovered from the solution. Esterification is rapid and proceeds essentially
to
completion. The esters may be used as biofuel or biodiesel.
Reference may be made to Patent No. WO 2005/052103A1 where in , they discloses
a
process for the preparation of biodiesel, whereby oil is subjected to
catalytical
transesterification, settling, separation, bubble washing and micro
filteration under
controlled conditions of temperature and turbulence. The process enables
production of
high quality fuel, termed as biodiesel within a period of as low as 50 hrs.
Reference may be made to US Patent No. 20060058540 where in , they discloses a
process for the preparation of fatty acid esters from fats and oils of
biological origin by
transesterification with monohydric alcohols in presence of basic catalyst,
the catalyst
using salts of basic organic compound and carbonic acid e.g. guanidine.
Reference may be made to US Patent. No. 6,440,057 where in , they described a
method for producing fatty acid methyl ester, compounding saturated and
unsaturated
higher fatty substances from atleast one of vegetable and animal fat with an
alkaline
solution of potassium dissolved in alcohol to form a mixture. The method also
includes
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emulsifying the mixture to reach a chemical balance state in a reaction
section. The
method further includes after reacting a chemical balance state, separating
residues
from the fatty acid methyl ester in a phase separation.
Reference may be made to Patent No. WO 00/05327/PCT/US99/16669 where in, they
described a process producing alkyl esters useful in biofuel and lubricant by
transesterifying glyceride or esterifying free fatty acid containing substance
in a critical
phase medium providing increased reaction rates, decreased loss of catalyst or
catalyst
activity and improved overall yield of desired product. Reaction temperatures
are
typically in the range from about 20 to 200 degrees with reaction pressures in
the range
of about 150 psig to 400 psig.
Reference may be made to US Pat. No. 5,424,466 where in, they described an
improved process for the production of esters from fatty substances having a
natural
origin and low molecular weight alcohols, in which the soaps and only
compounds
entrained in the alkaline phases are recycled by treating them, following
acidification
and separation, with a fraction of the glycerol phase produced, in the
presence of an
alkaline catalyst and for forming preferably a triglyceride or a partially
substituted
glyceride.
Reference may be made to US Patent No. 4303590 where in, they discloses
principle of
two step alcoholysis reaction and the product obtained in the first step is
separated from
the by-product glycerine and then subjected to the second alcoholysis reaction
followed
by admixing of an appropriate amount of water and phase separation so that the
undesirable impurities transfer into the aqueous layer and readily separated
from the
ester product.
Reference may be made to US Pat. 4164506 where in, they discloses a two step
process
in which esters of fatty acids are produced by esterifying free fatty acids of
unrefined
fats with a lower alcohol in presence of an acid catalyst e.g H2SO4 separating
the
product mixture into fat layer and the lower alcohol layer and then inter
esterification
reaction between the resulting refined fats and a lower alcohol with an alkali
catalyst.
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Reference may be made to US Patent No. 5,399,731 where in, they described
fatty acid
esters of lower monovalent alcohols by transesterification of fatty acid
glycerides in the
presence of basic catalyst e.g. sodium hydroxide. They claim the addition of
alkali for
neutralization of excess of FFA to lower the acid value.
Reference may be made to US Patent application 20060069274 wherein they
described
an industrial production process for ethyl ester (biodiesel) through two
separate
reactions, in two steps: 1) hydrolysis of glyceryl esters from vegetable oils
at an
approximate temperature of 60 C., at atm pressure splitting the glycerol
esters in free
fatty acids and glycerol and esterification of free fatty acids with hydrated
ethyl
alcohol. The reaction occurs in two separate columns each 1.0 meter high and
packed
with heterogeneous catalyst calcium and magnesium (Cao. Mgo) stones, each 1/15
the
size of the column diameter. The patent claims of a continuous process for
ethyl ester
production.
Reference may be made to US Pat.5,514820 where in, they claimed a continuous
process for the production of lower alkyl esters at temperatures up to 100 C
and under
pressure of upto 10 bar by reaction of fatty acid triglyceride containing less
than 1%
free fatty acid with a lower alcohol in two stages in the presence of
homogeneous
alkaline catalyst, the glycerol formed being removed after the first stage to
enable the
process to be carried out with high yields and with lower maintenance.
Reference may be made to Austria Pat. No. 388743B and Patent No. 386222 where
in,
they described the transesterification take place with a suitable monohydric
alcohol in
the presence of a basic transesterification catalyst. After removal of
glycerol phase
which contains the free fatty acids and most of the catalyst, and other
impurities in the
crude product, final residues of catalyst present in solution are removed from
the crude
ester phase using an acidic cation exchanger. The fatty acid ester mixture
obtained in
this way can be employed without further purification both as diesel
fuel/heating oil.
Reference may be made to US pat. 6,399,800 wherein, they claimed a method for
producing fatty acid alkyl esters from a feedstock, involving: (a) saponifying
the
feedstock with an alkali to form a saponified feedstock, (b) removing the
water from
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the saponified feedstock to form a dried saponified feedstock containing no
more than
about 19% water, (c) esterifying the dried saponifed feedstock with an alcohol
in
presence of an inorganic acid catalyst to form fatty acid alkyl esters even
with water
present at levels up to about 3 wt% and (d) recovering the fatty acid alkyl
esters.
Reference may be made to US Patent no. 20050274065 wherein they disclose a
process
for producing biofuels. The process may be enhanced by one or more of the
following:
1) applying microwave or RF energy; (2) passing reactants over a heterogeneous
catalyst; claim zeolite or cation exchange resin in H+ at sufficiently high
velocity to
achieve high shear conditions; (3) maintaining the reaction at a pressure at
or above
autogeneous pressure, claim 10-100 psig. Enhanced processes using one or more
of
these steps can results in higher process rates, higher conversion levels or
both.
Reference may be made to US Pat. 6,965,044 wherein, they described a method
for
converting free fatty acid in acid oil or acid fat into fatty acid methyl
esters is disclosed.
The process claims to use sulphuric acid as catalyst.
Reference may be made to US Pat. No. 5,525,126 wherein, they discloses a
single step
process for producing esters from a feedstock that includes a fat or an oil.
The process
includes mixing the feedstock with an alcohol, such as methanol and a catalyst
comprising of 3:1 by weight mixture of calcium acetate and barium acetate,
heating the
reaction mixture to 200-250 C to about 3 hrs and cooling the mixture rapidly.
The
process is claimed to produce esters from a oil having high free fatty acid
content such
as 50% by weight to make a mixture of esters to fatty acid in a ratio of about
96:4 by
weight.
Reference may be made to French Pat. No. FR2745296 wherein, they described a
process for transesterification of a vegetable or animal oil using a solid
heterogeneous
catalyst comprising the stage of : (i) mixing a vegetable or animal oil with
the required
amount of a low alcohol, a fatty alcohol, a petrochemical alcohol, a polyol or
a
carboxylic acid ester, (ii) maintaining the mixture under a protective
atmosphere to
avoid possible oxidation of ethylenic groups and to avoid possible oxidation
of the
glycerol produced; (iii) and maintaining the system at a temperature of >150
C,
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preferably 150-300 C in the presence of solid heterogenous catalyst based on
Sri, Ge or
Pb.
Reference may be made to US Pat. No. 20060014974 'wherein, they claimed a
process
for producing alkyl esters and glycerol of high purity comprising at least one
reaction
stage in which a charge comprising a vegetable and/or animal oil and an
alcohol in the
presence of a heterogeneous catalyst, Zinc aluminate, so as to obtain an
effluent
comprising atleast alkyl esters, glycerol and alcohol, and at lease one
separation stage
during which a separation stage consists of a membrane separating using at
lease one
alcohol-permeable membrane.
Reference may be made to US Pat. No. 6,822,105 wherein, they claimed a process
of
converting the free fatty acids of the oil source into a mixture of mono-di
and
triglycerides and subsequently transesterifying the newly formed glycerides as
well as
the originally present glycerides into fatty acid alkyl esters in presence of
dibutyl tin
oxide or tetra-butyl titanate at 180 C and reduced pressure being 760 mm/Hg to
1 mm
Hg.
Reference may be made to US Pat No. 6,712,987 wherein, they claimed a process
comprises forming a single phase solution of said triglyceride in an alcohol
methanol/ethanol and mixture the ratio of alcohol to triglyceride being 15:1
to 35:1 in
presence of a co solvent (tetrahydrofuran) in an amount to effect formation of
single
phase and a basic catalyst, NaOH/KOH for the esterification reaction.
Reference may be made to US Pat. No. 5,908,946 wherein, they described a
process for
the production of esters from acidic oil and methanol in presence of catalyst
Zno, at
170-250 and a pressure of 100 bar and the claims therein.
Reference may be made to US Pat. No. 20070083056 wherein, they claimed a
process
for the preparation of hydrocarbon fuels, which comprises contacting fatty
acid
glycerides with alcohols in the presence of a solid, double metal cyanide
catalyst at a
temperature in the range of 150 to 200 C for a period of 2-6 hrs and
separating the
catalyst from the above said reaction mixture to obtained the desired
hydrocarbon fuel.
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Reference may be made to patent W02007/083213 wherein, they described a
process
for preparation of biodiesel, which comprises the separation of the-
triglyceride
component from the free fatty acid one, both of which are contained in at
least one
biolipid, the esterification of said acid component, and the joint trans-
esterification of
the resulting esterified acid component with said triglyceride component. The
process
claims use of >60 moles of methanol for extraction of 0.300kg of fatty acids
in
9.700kg.triglycerides.
Reference may be made to a recent publication by S. Chongkhong et. al. in
Biomass
and Bioenergy Vol.31, Issue 8, August 2007, page 563-568 entitled "Biodiesel
production by esterification of palm fatty acid distillate" wherein Batch
esterification of
PFAD carried out to study the influence of. including reaction temperature of
70-100 C,
molar ratio of methanol to PFAD of 0.4:1-12:1, Catalyst quantity of 0.5- 5.5%
(Wt. of
sulphuric acid/wt. of PFAD and reaction time of 15-240 min).
In the production of methyl esters of fatty substances from refined oils and
dry alcohols,
while simple alkaline derivatives, such as sodium, soda or potassium
alcoholates, are
now used as catalysts, under rather mild conditions (temperature 50' to 80 C
and
atmospheric pressure), as indicated in numerous patents or publications, for
example in
JAOCS 61, 343-348 (1984), a pure product that can be used as a fuel and
glycerine
within specification can be obtained only after numerous stages and the
process may be
economically feasible to use the pretreated/refined oils and dry alcohols.
The major limitation associated with all these processes is that refined oils
e.g.
soyabean, rape seed etc. are used which are mostly edible having FFA<1%.
Another
limitation associated with these processes is high, temperature 200-250 C as
reported in
US Pat. No.: 5,525,126. Another limitation of reported process is high
temperature or
pressure e.g. in heterogenous solid catalyst US patent 5,908,946 or use of
critical phase
medium reported in W000/05327/PCT/US99/16669. Another limitation associated
with the process is the use of H2S04, which is corrosive and use of large
quantity of
alkali for neutralization creating disposal problems when such high FFA
feedstocks are
used as reported in Biomass and Bioenergy Vol.31, Issue 8, 2007,page 563-568.
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The cost of biodiesel process depends 70-80% on the cost of raw material. In
order to
achieve an economically feasible process it is desirable to use low cost raw
materials
e.g PFAD, soya deodistillate, acid oils restaurant grease, or waste cooking
oil, Jatropha
Curcas oil, mohua oil and animal fat for biodiesel process.
The novelty of the present invention lies in the esterification of feedstock
with high
FFA content (20-85 %) without any pretreatment for biodiesel in the presence
of
macroreticular and gel type acidic heterogeneous resin as catalyst which can
be used
repeatedly (3-4 cycles) and no filteration or washing is required after 1St
step of
esterification. The esterified oil can be directly taken up for
transesterification with
base catalyst.
OBJECTIVES OF THE INVENTION
The main object of the present invention is to provide a process for
conversion of low
cost and high FFA oils to biodiesel which obviates the drawbacks of the
hitherto known
prior art as detailed above.
Another objective of the present invention is to provide a process for
converting high
FFA containing feed stocks(' FFA 20-85 %) like palm fatty acid distillate
(PFAD),restaurant grease, waste cooking oil , Soya deo distillate, acid oil,
jatropha
curcas oil, mohua oil etc to biodiesel.
Yet another objective of the present invention is to provide the heterogenous
resin
either in a stainless steel basket or used directly with stirring to convert
high FFA
feedstock without neutralization or pretreatment.
Still another objective of present invention is to use heterogenous resin
repeatedly in
the 1st step (4-5cycles) with lower alcohol.
Yet another objective of the present invention is use of flexible feedstock
without
pretreatment or purification.
Still another objective of present invention is to produce biodiesel at normal
temperature and pressure from flexible feed stock having FFA 20-85% meeting
the fuel
grade quality as specified by ASTM/BIS.
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SUMMARY OF INVENTION
Accordingly, the present invention provides a process for converting high free
fatty
acid containing feedstocks (FFA 20-85 %) into biodiesel which comprises:
a. providing feed stocks containing 20-85 % FFA without pretreatment or
purification;
b. esterifying the feed stocks with lower alcohols in the presence of
macroreticular and gel type acidic heterogeneous resin as catalyst;
c. heating the reactants of step (b) at a temperature in the range of 55-65 C
followed by mechanical stirring for a time period of 8 to 10 hours to
obtain esterified oil;
d. subjecting the esterified oil as obtained from step (c) to
transesterification in the presence of homogeneous basic catalyst and
methanol;
e. separating product as obtained from step (d) into upper layer biodiesel
and lower layer glycerol followed by recovering of methanol;
f. washing the biodiesel layer as obtained from step (e) with hot water
followed by drying to obtain biodiesel.
20' In an embodiment of the invention, the feedstocks containing 20-85% FFA
are
selected from the group consisting of palm fatty acid distillate (PFAD),
restaurant
grease, waste cooking oil, Soya deo distillate, acid oil, jatropha curcas oil
and
mohua oil.
In another embodiment of the invention, the lower alcohols used for
esterification is
selected from the group consisting of methanol, ethanol or propanol in the
ratio of
3:1 to 35:1 depending upon feedstock.
In another embodiment of the invention, the acidic heterogeneous resin
catalyst is
provided either in a jacketed glass reactor with stainless steel basket or
used directly
with stirring for esterification process without neutralization or
pretreatment.
In another embodiment of the invention, wherein the acidic heterogeneous resin
catalyst in a basket is used repeatedly (4-5 cycles).
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In another embodiment of the invention, the acidic heterogeneous resin
catalyst
used ' for esterification is selected from the group consisting of Tulsion-42
and
Indion -130.
In another embodiment of the invention, the catalyst Tulsion-42 is used in the
range
of 5-20 % by weight of the feed stocks and Indion -130 is used in the range of
5-25
% by weight of the feed stocks.
In another embodiment of the invention, homogeneous basic catalyst used for
transesterification is selected from the group consisting of sodium hydroxide,
potassium hydroxide, sodium methoxide and potassium methoxide.
In another embodiment of the invention, the transesterification is carried out
at a
temperature in the range of 55-70 C for a period of 1 to 2 hrs.
In yet another embodiment of the invention, biodiesel is purified by washing
with
water or by distillation or adsorbent or combinations thereof.
DETAILED DESCRIPTION OF THE INVENTION
Weighed quantity of oil (1 mol) and (3-4.5 mol) methanol were taken in the
first step in
presence of 5 - 20 % of macroreticular and gel type acidic heterogeneous resin
catalyst
(available commercially) in a stainless steel basket in a jacketed reactor. In
case of low
cost high free fatty acid oils (FFA>50%) e.g. Palm free acid distillate (PFAD)
even 30-
35 mol of methanol were taken. The reaction was carried out at a temperature
of
60 20C. After completion of 1St step as monitored by acid value after an
interval of 2
hrs, the product with acid value in the range of 1-2mgKOH/g were
transesterified in
presence of homogeneous catalyst 0.5-0.75% using 2-3mol of methanol at a
temperature of 55-70 C fora period of 1 to 2 hrs. After completion of
reaction in 1-2
hrs, depending upon feedstock the biodiesel and glycerol layers were separated
and the
work up resulted in fuel grade biodiesel meeting ASTM/BIS specifications.
The following examples are given by way of illustration of the working of
invention in
actual practice and should not be construed to limit the scope of the present
invention.
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Example-1
101.639 gms of Jatropha curcas oil having acid value 40 mgKOH/g, 16.529gm of
methanol were taken in a jacketed glass reactor with SS basket loaded with
5.128 (5%)
gms of catalyst Tulsion-42 (available commercially). The reactants were heated
to 60 C
with mechanical stirring. The progress of reaction was studied by determining
acid
value after 2 hrs interval. The acid value after 12 hrs was 3.47 mgKOH/g
respectively.
The esterified oil was then taken in another jacketed reactor and the oil was
transesterified with 0.5% potassium hydroxide in presence of 7.2g methanol at
65 C the
reaction was complete in one hour. The stirring was stopped and the contents
were
allowed to settle down, after separating glycerol and upper layer
(biodiesel)methanol
recovered. The upper layer of biodiesel was washed with hot water (60 C), lot
of
emulsion was formed in first two washings due to formation of soaps. The
conversion
of biodiesel observed was 80% only.
Example - 2
Example I was repeated except that 10.02 g (10%) of catalyst Tulsion-42 was
taken
and acid value is 2.70 mgKOH/g after interval of 8 hrs respectively. The
esterified
Jatropha curcas oil was taken in second reactor and the transesterification
was carried
out in presence of 0.75%.of potassium hydroxide with 15g methanol at 60 C. The
reaction was complete in one hour, stirring stopped. The glycerol and
biodiesel layers
were separated, methanol recovered, the biodiesel layer was washed with water,
and
there was slight ` emulsion formation water in first two washings in total of
four
washings. The biodiesel dried and acid value of biodiesel was 0.46mg KOII /g
and the
conversion to biodiesel was 98%.
Example -3
Example 1 was repeated except that 15.37 gins (15%) of catalyst Tulsion -42
was
loaded and acid value after 8 hrs is 2.12 mg KOH/g respectively. The
esterified
Jatropha curcas oil was taken in second reactor and the transesterification
was carried
out in presence of 0.75% of potassium hydroxide with methanol (21.6 g) at 65 C
The
reaction was completed in one hour, stirring stopped. The glycerol and
biodiesel layers
were separated, methanol recovered the biodiesel layer was washed with water,
in first
two washings there was slight emulsion formation in total of four washings,
the
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biodiesel dried and acid value of biodiesel was 0.45mg KOH /g and the
conversion to
biodiesel was observed 99 %.
Example-4
Example 1 was repeated except that catalyst Tulsion-42 was replaced by 10.49
gms
(10%) of Indion-130 (available commercially) and acid value after 8 hrs was
10.24
mgKOH/g. The esterified Jatropha curcas oil was taken in second reactor and
the
transesterification was carried out in presence of 0.75%of potassium hydroxide
with
(15g) methanol at 65 C The reaction was complete in one hour, stirring
stopped. The
glycerol and biodiesel layers were separated, methanol recovered, the
biodiesel layer
was washed with water, in first three washings there was emulsion formation in
total of
six washings. The biodiesel dried and acid value of biodiesel was 1.83 KOH /g
and the
conversion to biodiesel was 68.9%
Example-5
Example 4 was repeated and Indion-130 (15%) was loaded and acid value is 5.55
after
8 hrs. The esterified Jatropha curcas oil was taken in second reactor and the
transesterification was carried out in presence of 0.75% of potassium
hydroxide with
(21.6g) of methanol at 70 T. The reaction was complete in one hour, stirring
stopped.
The glycerol and biodiesel layers were separated, methanol recovered, the
biodiesel
layer was washed with water, in first two washings there was emulsion
formation in
total of four washings. The biodiesel dried and acid value of biodiesel was
0.95mg
KOH /g and the conversion to biodiesel was 79.2%
Example-6
Example 5 was repeated with 20% Indion-130 and acid value after 8 hrs was 1.99
mgKOH/g. The esterified Jatropha curcas oil was taken in second reactor and
the
transesterification was carried out in presence of 0.75%of potassium hydroxide
(20.9g)
of methanol at 65 C. The reaction was completed in one hour, stirring stopped.
The
glycerol and biodiesel layers were separated, methanol recovered, the
biodiesel layer
was washed with water, in first washing there was slight emulsion formation in
total of
four washings. The biodiesel dried and acid value of biodiesel was 0.52mg KOH
/g and
the conversion to biodiesel was 98%.
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Example-7
100.84 gms of Mohua oil having acid value 44 mg KOH/g, 17.49gms of methanol
were
taken in a jacketed glass reactor with SS basket loaded with 15.37 gms (15%)
of
Tulsion-42. The reactants were heated to 62 C with mechanical stirring. The
acid value
after 8 hrs wasl.87 mgKOH/g. The esterified oil was then taken in another
jacketed
reactor and the oil was transesterified with 0.75% potassium hydroxide in
presence of
6.94gms of methanol at 65 C. The reaction was completed in one hour. The
stirring
was stopped and the contents were allowed to settle down after separating
glycerol and
biodiesel, methanol was recovered. The upper layer of biodiesel was washed
with hot
water, in first two washings there was slight emulsion formation in total of
four
washings, the biodiesel dried and acid value of biodiesel was0.42 mg KOH /g
and the
conversion to biodiesel was observed 95%.
Example-8
Example 7 is repeated except that raw material taken was restaurant Grease
having acid
value 34 mg KOH/g. The acid value after 8 hrs was 1.92 mgKOH/g Each esterified
oil
was then worked up in the same procedure as in example 7. The acid value of
biodiesel
is 0.39mgKOH/g and the conversion to biodiesel was observed 97%.
Example- 9
Example 7 is repeated except that raw material taken was soya deodistillate
having acid
value 38 mg KOH/g. The acid value after 8 hrs was 2.lmgKOH/g The esterifed oil
was then worked up in the same procedure as in example 7. The acid value of
biodiesel
was0.47 mg KOH /g and the conversion to biodiesel was observed 94%.
Example-10
Examples 7-9 were repeated except that Indion-130 (15%) is used instead of
Tulsion-42.
The acid value of mohua oil, restaurant grease and soya deodistillate were
44mg
KOH/g, 34mg KOH/g and 38 mg KOH/g respectively. Each esterified oil was 'then
worked up in the same procedure as in examples 7, the acid value of biodiesel
were
0.42mg KOH/g,0.39mg KOH/g and 0.48mg KOH/g respectively and the conversion to
biodiesel was observed 95%, 97% and 94%.
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Example -11
100.86 gms of palm fatty acid distillate (PFAD) having acid value 177 mg KOI--
I/g,
29.11 gms of methanol and 20.17 gms (20%) of heterogeneous resin Indion-130
catalyst were taken in a jacketed glass reactor in a SS basket. The acid value
is lowered
to 53.21 mgKOH/g after 8 hrs. The material could neither be neutralized nor
transesterified because of such high acid value showing incomplete conversion
of
PFAD.
Example-12
Example 11 is repeated except that methanol is 216.49 gms (30moles). The acid
value
after removal of methanol is 4.12, 3.34, 3.17, 3.10 mgKOH/g after 2, 4, 6 and
8 hrs
respectively.
Example-13
Example 12 is repeated except that Tulsion-42 (15%) is used instead of Indion-
130.
The acid value is 2.93 mg KOH/g after 8 hrs.
Example-14
Example 11 and 12 are repeated and the converted feed/biodiesel is purified by
neutralization with NaOH and viscosity of fatty acid methyl ester at 40 C is
5.82 cSt
(centistokes) after drying and washing.
Example-15
100.86 gms, of palm fatty acid distillate (PFAD) having acid value 177 mg
KOII/g,
216.49 gms of methanol and 20.17 gms (20%) of heterogeneous resin Indion-130
catalyst or15.78 (15%) of Tulsian-42 were taken in a jacketed glass reactor in
a SS
basket. The acid value is lowered to 2.93mgKOH/g after 8 hrs. After the
reaction the
unreacted methanol is recovered and the product is neutralized with 0.5M NaOH
(50m1).Washing with hot water (65 C) remove traces of glycerol and drying to
remove
moisture.The product has viscosity of 5.82 cSt at 40 c.
Example 15 is repeated and the feed is distilled off to get fuel grade palm
fatty acid
methyl ester with viscosity 4.47 cSt at 40 C and acid value 0.42-0.44 mg
KOH/g.
CA 02774343 2012-03-13
WO 2011/033346 15 PCT/IB2010/000592
THE MAIN ADVANTAGES OF PRESENT INVENTION ARE:
1) Low cost and high FFA feed stock, Restaurant Grease, Waste Cooking oil,
PFAD, Soya distillate, acid oil, Jatropha curcas oil and Mohua oil can be used
for biodiesel production.
2) Another advantage of the process is using heterogeneous resins in SS basket
where no filteration of converted feed stock is required after 1St stage.
3) Another important advantage is the repeated use (4-5 cycles) of
heterogeneous
resin.
4) Another advantage is that flexible feedstocks can be used without
pretreatment
or neutralization.
5) The another important advantages is by using such low cost feed stock and
repeated use of heterogeneous resin under mild conditions. The process is
economically viable.
6) Yet another important advantage is the least disposal problems as no
washing is
required after 1St stage/esterification.
