U.S. patent application number 10/718559 was filed with the patent office on 2005-05-26 for process for the preparation of bio-diesel.
This patent application is currently assigned to Council of Scientific and Industrial Research of Rafi Marg. Invention is credited to Rao, Paruchuri Gangadhar, Saravanan, Subramani, Vedaraman, Nagarajan, Velappan, Kandukalpatti Chinnaraj.
Application Number | 20050108927 10/718559 |
Document ID | / |
Family ID | 34740776 |
Filed Date | 2005-05-26 |
United States Patent
Application |
20050108927 |
Kind Code |
A1 |
Velappan, Kandukalpatti Chinnaraj ;
et al. |
May 26, 2005 |
Process for the preparation of bio-diesel
Abstract
A process is disclosed for the preparation of biodiesel, whereby
oil is subjected to catalytical transesterification, settling,
separation, bubble washing and micro filtration at controlled
conditions of temperature and turbulence. The process enables
production of high quality fuel, termed as biodisel, within a
period of as low as 50 hrs. The fuel can be used without blending
with any conventional fuel.
Inventors: |
Velappan, Kandukalpatti
Chinnaraj; (Chennai, IN) ; Saravanan, Subramani;
(Chennai, IN) ; Vedaraman, Nagarajan; (Chennai,
IN) ; Rao, Paruchuri Gangadhar; (Chennai,
IN) |
Correspondence
Address: |
NIXON PEABODY, LLP
401 9TH STREET, NW
SUITE 900
WASHINGTON
DC
20004-2128
US
|
Assignee: |
Council of Scientific and
Industrial Research of Rafi Marg
New Delhi
IN
|
Family ID: |
34740776 |
Appl. No.: |
10/718559 |
Filed: |
November 24, 2003 |
Current U.S.
Class: |
44/605 |
Current CPC
Class: |
C11C 3/10 20130101; Y02E
50/10 20130101; C10L 1/026 20130101; C11C 3/003 20130101; C07C
67/03 20130101; Y02E 50/13 20130101; C07C 67/03 20130101; C07C
69/52 20130101; C07C 67/03 20130101; C07C 69/24 20130101 |
Class at
Publication: |
044/605 |
International
Class: |
C10L 005/00 |
Claims
1. An improved process for the preparation of bio-diesel, which
comprises i) heating oil having by specific gravity in the range of
0.85-0.96 and iodine value not exceeding 208, to a temperature not
exceeding 120.degree. C. for not less than 2 hrs followed by
transesterification with 8 to 42% w/w, of alcohol of general
formula R-OH, where R represents (C.sub.nH.sub.2n+1), n being any
integer between 1 and 5, in presence of not more than 0.55% w/w, of
a catalyst, at a temperature higher than the boiling point of the
alcohol but not exceeding 215.degree. C. for a period of not less
than 30 minutes under continuous turbulent conditions to obtain a
mixture of ester and glycerol, ii) Subjecting the mixture, as
formed in step (i) to separation of the esterified oil for a period
of not less than 4 hrs followed by purification for a period of not
less than 8 hrs. and repeating the process of separation as well as
purification in succession for not less than three times to obtain
biodiesel.
2. A process, as claimed in claim 1 wherein the oil is selected
from ricebran oil, cottonseed oil , soybean oil, sunflower oil ,
castor oil, coconut oil.
3. A process, as claimed in claim 1, wherein the alcohol is
selected from methanol, ethanol, n-propanol, n-butanol, and
n-pentanol
4. A process, as claimed in claim 1 wherein the catalyst is
selected from sodium hydroxide, potassium hydroxide.
5. A process, as claimed in claim 1 wherein the esterified oil is
separated by decanting, centrifuging, gravity separation, settling,
either alone or in any combination.
6. A process, as claimed in claim 1 wherein the purification of the
mixture is by bubble washing involving bubble size of 1-3 mm, micro
filtration with not less than 5 micron filter, centrifuging, either
alone or in any combination.
7. A process, as claimed in claim 1 wherein the Reynolds number
(N.sub.Re) for maintaining turbulence is adjusted at not less than
4000 irrespective of the type of reactor.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to an improved process for the
preparation of bio-diesel. It has enormous potential application in
automobile industry as a substitute fuel for diesel.
BACKGROUND OF THE INVENTION
[0002] Biodiesel has of late been recognized as an efficient fuel
substitute. As reported by Anjana Srivastava and Ram Prasad
(Renewable & Sustainable Energy Reviews--4, 2000, p111-133,)
renewable sources such as vegetable oils, animal fats and used
cooking oils are normally used as the starting material for
preparing this alternate source of fuel. There are also reports
that, the engine problems due to carbonization of combustion
chamber and wax deposits & engine failure.
[0003] As reported by Gerhard Vellguth (Society of Automobile
Engines No. 831358, 1983), the fuel injector modifications are
needed in standard diesel engines while using vegetable oil as a
fuel , otherwise forms deposits on the injectors and in the
cylinder head, leading to poor performance, higher emissions and
reduces engine life. This limitation has to some extent been
resolved by way of transesterification. Reference may be made to
Antolin et al., (Bioresource Technology 83, 2002, p 111-114), who
transesterified sunflower oil with methanol at a temperature in the
range of 40-70.degree. C. under constant stirring for a period of
2-6 hrs. Similar efforts have been made by different research
groups to prepare biodiesel from multiple oil sources. As reported
by Alcantara et al., (Biomass Bioenergy 18,p515-527,2000) several
oils such as soybean, frying oil, tallow have been tried as
substitutes for diesel. As reported by Widyan and Shyoukh
(Bioresource Technology 85, p253-256,2002), palm oil has also been
tried as substitutes.
[0004] Conventionally, biodiesel is prepared from oil by reacting
with alcohol using a acid/alkali/enzyme catalyst in the temperature
range of 40-80.degree. C. under constant stirring for a period of
2-6 hrs. In order to achieve higher product conversion, 1-3 moles
per moles of oil in excess to stoichemetric quantity of alcohol is
normally used and the unreacted alcohol is removed in the
subsequent process steps. The ester obtained is separated from
glycerine by suitable separation process and the ester is washed
with mild acid. The product is purified further by evaporation to
remove unreacted alcohol and traces of moisture. The final product
is normally used in combination with regular petroleum fuels to
overcome the viscosity and related problems.
[0005] The major limitation associated with all these processes is
that the overall product conversion in most of the cases is limited
to 60-85% only. Moreover, the temperature range limited up to
60.degree. C. results in prolonged time, which may be as high as 6
hrs and thereby enhancing the cost of the process
significantly.
[0006] Another limitation associated with these processes is that
the resulting product exhibits higher viscosity compared with
conventional petroleum fuels, thereby necessitating it is blending
with petroleum fuels for the use in diesel engines.
OBJECTS OF THE INVENTION
[0007] The main object of the present invention is to provide an
improved process for the preparation of bio-diesel which obviates
the limitations as stated above.
[0008] Another object of the present invention is to provide a
chemical process for biodiesel with renewable sources of
energy.
[0009] Still another object of the present invention is to provide
a chemical process for biodiesel oil preparation from extracted
from agricultural edible and non-edible products.
[0010] Yet another object of the present invention is to provide an
environmentally friendly fuel.
[0011] Still yet another object of the present invention is to
provide an improved quality of biodiesel can be used with out any
alteration in the diesel engine.
[0012] Accordingly the present invention provides an improved
process for the preparation of bio-diesel, which comprises
[0013] i) heating oil, characterized by specific gravity in the
range of 0.85-0.96 and iodine value not exceeding 208, to a
temperature not exceeding 120.degree. C. for not less than 2 hrs
followed by transesterification with 8 to 42% w/w, of alcohol of
general formula R-OH, where R represents (C.sub.nH.sub.2n+1), n
being any integer between 1 and 5, by known method in presence of
not more than 0.55% w/w, of a known catalyst, at a temperature
higher than the boiling point of the alcohol but not exceeding
215.degree. C. for a period of not less than 30 minutes under
continuous turbulent condition to get mixture of ester and
glycerol,
[0014] ii) subjecting the mixture, as formed in step(i) to
separation of the esterified oil by known method for a period of
not less than 4 hrs followed by conventional purification for a
period of not less than 8 hrs. and repeating the process of
separation as well as purification in succession for not less than
three times to get biodiesel.
[0015] In an embodiment of the present invention the oil used may
be selected from ricebran oil, cottonseed oil , soybean oil,
sunflower oil, castor oil, coconut oil.
[0016] In another embodiment of the present invention the alcohol
used may be selected from methanol, ethanol, n-propanol, n-butanol,
n-pentanol
[0017] In yet another embodiment of the present invention the
catalyst used may be selected from sodium hydroxide, potassium
hydroxide.
[0018] In still another embodiment of the present invention, the
known method of separation used may be such as decanting,
centrifuging, gravity separation, settling.
[0019] In yet another embodiment of the present invention the
conventional method of purification used may be selected from
bubble washing involving bubble size of 1-3 mm, micro filtration
with not less than 5 micron filter, centrifuging, either alone or
in any combination.
[0020] In still another embodiment of the present invention, the
Reynolds number (N.sub.Re) used for maintaining turbulence may be
adjusted at not less than 4000 irrespective of the type of
reactor.
[0021] The process of the present invention is described below in
detail.
[0022] Oil having specific gravity in the range of 0.85-0.96 and
iodine value not exceeding 208 is heated to a temperature not
exceeding 120.degree. C. for not less than 2 hrs and is
transesterified using 8 to 42% w/w, of alcohol of general formula
R-OH, where R represents (C.sub.nH.sub.2n+1), n being any integer
between 1 and 5, by known method in presence of not more than 0.5%
w/w, of a known catalyst, at a temperature higher than the boiling
point of the alcohol but not exceeding 215.degree. C. for not less
than 30 minutes under continuous turbulent condition at rpm in the
range of 100-150 to get a mixture of ester and glycerol. The
Reynolds number (N.sub.Re) is maintained at not less than 4000
irrespective of the type of the reactor.
[0023] The mixture of ester and glycerol is subjected to separation
by known method for a period of not less than 4 hrs and the top
layer ester is purified by conventional method for a period of not
less than 8 hrs. The process of separation as well as purification
is repeated for not less than three times in succession to get
biodiesel.
[0024] The inventive step of the present invention lies not only in
selecting the temperature of transesterification at higher than the
boiling point of the alcohol while not exceeding 215.degree. C.,
but also in maintaining turbulence monitored by adjusting the
Reynolds number (N.sub.Re) at not less than 4000 irrespective of
the type of the reactor, to ensure about 97% conversion of the oil
into ester within a period of as low as 30 minutes, thereby
enhancing the formation of fuel properties in the resulting product
called biodiesel.
[0025] The following examples are given by way of illustration only
and therefore should not be construed to limit the scope of the
present invention.
EXAMPLE 1
[0026] 100 ml of rice bran oil having a moisture content of 3% was
heated at 120.degree. C. for a period of 2 hrs. Later the moisture
content of the oil was found to be 0.5%. This oil was taken in the
specially modified batch Continuous Stirred Tank Reactor (CSTR)
with provision for alcohol recycle/recovery system, condenser,
thermometer and feeding funnel. 20 ml of methanol was taken in a
beaker and 0.5 gm sodium hydroxide was added to it under continuous
stirring. The resulting solution was then added to the reactor
rapidly. The reactor system was maintained at turbulent condition
by stirring at 100 rpm in order to maintaining the Reynolds number
(N.sub.Re) at the minimum of 4000. The reaction was continued for
30 minutes. The excess methanol of 4 ml used for above reaction was
later is recovered.
[0027] The resulting solution was taken in separating funnel, and
two layers were found to form. The mixture was allowed to settle
for 4 hrs and the top layer was taken for further processing.
[0028] This was then subjected to bubble washing by aeration with
15 ml of distilled water for a period of 8 hrs and the resulting
material was allowed to settle for 8 hrs. It was taken for micro
filtration to remove the micro particles present in the product.
The bubble washing, settling and filtration operations were
repeated for two more times to attain improved fuel properties. The
resulting biodiesel was stored.
[0029] 97% of rice bran oil was estimated to has been converted
into biodiesel, which was found to meet the specifications of
conventional petroleum fuel. The biodiesel was used for running a
test engines. The emission properties of this biodiesel were found
to be better than of the conventional fuels.
EXAMPLE 2
[0030] 100 ml of rice bran oil having a moisture content of 3% was
heated at 120.degree. C. for a period of 2 hrs. Later the moisture
content of the oil was found to be 0.5%. This oil was taken in the
specially modified batch Continuous Stirred Tank Reactor (CSTR)
with provision for alcohol recycle/recovery system, condenser,
thermometer and feeding funnel. 32 ml of propanol was taken in a
beaker and 0.5 gm sodium hydroxide was added to it under continuous
stirring. The resulting solution was then added to the reactor
rapidly. The reactor system maintained at turbulent condition by
stirring at 100-rpm in order to maintaining the Reynolds number
(N.sub.Re) at the minimum of 4000. The reaction was continued for
30 minutes. The excess methanol of 7 ml used for above reaction was
later is recovered by the special recovery system. The resulting
solution was taken in separating funnel, and two layers were found
to form. The mixture was allowed to settle for 4 hrs and the top
layer was taken for further processing.
[0031] This was then subjected to bubble washing by aeration with
25 ml of distilled water for a period of 8 hrs and the resulting
material was allowed to settle for 8 hrs. It was taken for micro
filtration to remove the micro particles present in the product.
The bubble washing, settling and filtration operations were
repeated for two more times to attain improved fuel properties. The
resulting biodiesel was stored.
[0032] 95% of rice bran oil was estimated to has been converted
into biodiesel, which was found to meet the specifications of
conventional petroleum fuel. The biodiesel was used for running a
test engines. The emission properties of this biodiesel were found
to be better than of the conventional fuels.
EXAMPLE 3
[0033] 100 ml of sunflower oil having a moisture content of 1.5%
was heated at 120.degree. C. for a period of 2 hrs. Later the
moisture content of the oil was found to be 0.5%.
[0034] This oil was taken in the specially modified batch
Continuous Stirred Tank Reactor (CSTR) with provision for alcohol
recycle/recovery system, condenser, thermometer and feeding funnel.
40 ml of butanol was taken in a beaker and 0.5 gm sodium hydroxide
was added to it under continuous stirring. The resulting solution
was then added to the reactor rapidly. The reactor system
maintained at turbulent condition by stirring at 100-rpm in order
to maintaining the Reynolds number (N.sub.Re) at the minimum of
4000. The reaction was continued for 30 minutes. The excess butanol
of 8.3 ml used for above reaction was later is recovered by the
special recovery system.
[0035] The resulting solution was taken in separating funnel, and
two layers were found to form. The mixture was allowed to settle
for 4 hrs and the top layer was taken for further processing.
[0036] This was then subjected to bubble washing by aeration with
15 ml of distilled water for a period of 8 hrs and the resulting
material was allowed to settle for 8 hrs. It was taken for micro
filtration to remove the micro particles present in the product.
The bubble washing, settling and filtration operations were
repeated for two more times to attain improved fuel properties. The
resulting biodiesel was stored.
[0037] 98.0% of sunflower oil was estimated to have been converted
into biodiesel, which was found to meet the specifications of
conventional petroleum fuel. The biodiesel was used for running a
test engines. The emission properties of this biodiesel were found
to be better than of the conventional fuels.
EXAMPLE 4
[0038] 200 ml of coconut oil having a moisture content of 2% was
heated at 120.degree. C. for a period of 2 hrs. Later the moisture
content of the oil was found to be 0.5%.
[0039] This oil was taken in the specially modified batch
Continuous Stirred Tank Reactor (CSTR) with provision for alcohol
recycle/recovery system, condenser, thermometer and feeding funnel.
47 ml of methanol was taken in a beaker and 1 gm sodium hydroxide
was added to it under continuous stirring. The resulting solution
was then added to the reactor rapidly. The reactor system
maintained at turbulent condition by stirring at 100-rpm in order
to maintaining the Reynolds number (N.sub.Re) at the minimum of
4000. The reaction was continued for 60 minutes. The excess
methanol of 10 ml used for above reaction was later is recovered by
the special recovery system.
[0040] The resulting solution was taken in separating funnel, and
two layers were found to form. The mixture was allowed to settle
for 8 hrs and the top layer was taken for further processing.
[0041] This was then subjected to bubble washing by aeration with
15 ml of distilled water for a period of 8 hrs and the resulting
material was allowed to settle for 8 hrs. It was taken for micro
filtration to remove the micro particles present in the product.
The bubble washing, settling and filtration operations were
repeated for two more times to attain improved fuel properties. The
resulting biodiesel was stored.
[0042] 98.0% of coconut oil was estimated to have been converted
into biodiesel, which was found to meet the specifications of
conventional petroleum fuel. The biodiesel was used for running a
test engines. The emission properties of this biodiesel were found
to be better than of the conventional fuels.
EXAMPLE 5
[0043] 100 ml of coconut oil having a moisture content of 2% was
heated at 120.degree. C. for a period of 2 hrs. Later the moisture
content of the oil was found to be 0.5%.
[0044] This oil was taken in the specially modified batch
Continuous Stirred Tank Reactor (CSTR) with provision for alcohol
recycle/recovery system, condenser, thermometer and feeding funnel.
35 ml of ethanol was taken in a beaker and 0.5 gm sodium hydroxide
was added to it under continuous stirring. The resulting solution
was then added to the reactor rapidly. The reactor system
maintained at turbulent condition by stirring at 100-rpm in order
to maintaining the Reynolds number (N.sub.Re) at the minimum of
4000. The reaction was continued for 45 minutes. The excess ethanol
of 8 ml used for above reaction was later is recovered by the
special recovery system.
[0045] The resulting solution was taken in separating funnel, and
two layers were found to form. The mixture was allowed to settle
for 8 hrs and the top layer was taken for further processing.
[0046] This was then subjected to bubble washing by aeration with
15 ml of distilled water for a period of 8 hrs and the resulting
material was allowed to settle for 8 hrs. It was taken for micro
filtration to remove the micro particles present in the product.
The bubble washing, settling and filtration operations were
repeated for two more times to attain improved fuel properties. The
resulting biodiesel was stored.
[0047] 97.0% of coconut oil was estimated to have been converted
into biodiesel, which was found to meet the specifications of
conventional petroleum fuel. The biodiesel was used for running a
test engines. The emission properties of this biodiesel were found
to be better than of the conventional fuels.
EXAMPLE 6
[0048] 100 ml of sunflower oil having a moisture content of 1.5%
was heated at 120.degree. C. for a period of 2 hrs. Later the
moisture content of the oil was found to be 0.5%.
[0049] This oil was taken in the specially modified batch
Continuous Stirred Tank Reactor (CSTR) with provision for alcohol
recycle/recovery system, condenser, thermometer and feeding funnel.
20 ml of methanol was taken in a beaker and 0.5 gm sodium hydroxide
was added to it under continuous stirring. The resulting solution
was then added to the reactor rapidly. The reactor system
maintained at turbulent condition by stirring at 100-rpm in order
to maintaining the Reynolds number (N.sub.Re) at the minimum of
4000. The reaction was continued for 30 minutes. The excess
methanol of 4 ml used for above reaction was later is recovered by
the special recovery system. The resulting solution was taken in
separating funnel, and two layers were found to form. The mixture
was allowed to settle for 4 hrs and the top layer was taken for
further processing.
[0050] This was then subjected to bubble washing by aeration with
15 ml of distilled water for a period of 8 hrs and the resulting
material was allowed to settle for 8 hrs. It was taken for micro
filtration to remove the micro particles present in the product.
The bubble washing, settling and filtration operations were
repeated for two more times to attain improved fuel properties. The
resulting biodiesel was stored.
[0051] 98.0% of sunflower oil was estimated to have been converted
into biodiesel, which was found to meet the specifications of
conventional petroleum fuel. The biodiesel was used for running a
test engines. The emission properties of this biodiesel were found
to be better than of the conventional fuels.
EXAMPLE 7
[0052] 100 ml of sunflower oil having a moisture content of 1.5%
was heated at 120.degree. C. for a period of 2 hrs. Later the
moisture content of the oil was found to be 0.5%.
[0053] This oil was taken in the specially modified batch
Continuous Stirred Tank Reactor (CSTR) with provision for alcohol
recycle/recovery system, condenser, thermometer and feeding funnel.
25 ml of ethanol was taken in a beaker and 0.5 gm sodium hydroxide
was added to it under continuous stirring. The resulting solution
was then added to the reactor rapidly. The reactor system
maintained at turbulent condition by stirring at 100-rpm in order
to maintaining the Reynolds number (N.sub.Re) at the minimum of
4000. The reaction was continued for 30 minutes. The excess ethanol
of 8 ml used for above reaction was later is recovered by the
special recovery system.
[0054] The resulting solution was taken in separating funnel, and
two layers were found to form. The mixture was allowed to settle
for 4 hrs and the top layer was taken for further processing.
[0055] This was then subjected to bubble washing by aeration with
15 ml of distilled water for a period of 8 hrs and the resulting
material was allowed to settle for 8 hrs. It was taken for micro
filtration to remove the micro particles present in the product.
The bubble washing, settling and filtration operations were
repeated for two more times to attain improved fuel properties. The
resulting biodiesel was stored.
[0056] 98.0% of sunflower oil was estimated to have been converted
into biodiesel, which was found to meet the specifications of
conventional petroleum fuel. The biodiesel was used for running a
test engines. The emission properties of this biodiesel were found
to be better than of the conventional fuels.
Emission Analysis of Diesel, Biodiesel and Various Blends
[0057]
1 Load Time for CO CO.sub.2 HC O.sub.2 NOx Noise T.sub.exh KW
Sample 10 cc(sec) (% vol) (% vol) (ppm) (% VOL) (ppm) (db)
(.degree. c.) 0 Diesel 65 0.08 2.1 28 17.53 180 145 140 Biodiesel
65 0.04 2.55 10 17.10 111 116 182 BS1 66 0.02 2.31 0 17.30 154 145
153 BS2 71 0.02 2.14 0 17.50 96 112 154 BS3 69 0.03 2.13 0 17.36
125 113 145 BS4 69 0.03 2.42 5 17.28 113 120 170 BS5 78 0.04 2.09 0
17.47 84 115 169 4 Diesel 49 0.12 3.5 43 15.62 397 145 210
Biodiesel 45 0.04 3.95 20 15.27 118 119 202 BS1 51 0.03 3.61 0
15.70 369 120 190 BS2 49 0.03 3.49 27.5 15.57 277 112 196 BS3 48
0.03 3.84 20 14.94 300 115 180 BS4 49 0.04 3.90 17.5 16.39 283 129
245 BS5 48 0.045 4.02 2.5 14.99 300 116 242 7 Diesel 42 0.13 4.3 63
14.68 582 146 243 Biodiesel 36 0.03 5.06 10 13.53 525 121 277 BS1
46 0.04 4.11 35 14.73 473 117 210 BS2 39 0.04 4.87 12.5 13.56 502
114 225 BS3 38 0.05 5.44 10 12.67 479 116 243 BS4 38 0.05 5.20 10
13.18 496 126 285 BS5 38 0.06 5.46 32.5 12.85 451 119 315 11 Diesel
32 0.2 6.3 85 11.2 689 159 287 Biodiesel 30 0.05 6.74 20 10.99 727
123 329 BS1 32 0.06 6.79 37.5 10.53 800 119 250 BS2 29 0.06 6.91 15
10.43 728 118 240 BS3 30 0.10 7.05 15 10.15 608 119 285 BS4 30 0.10
7.35 45 9.83 605 126 296 BS5 30 0.11 7.01 30 10.36 616 121 362 14
Diesel 27 0.34 7.7 89 9.12 942 169 294 Biodiesel 25 0.09 8.30 35
8.74 904 124 411 BS1 27 0.07 7.58 35 9.24 977 120 266 BS2 26 0.18
8.04 47.5 8.54 858 119 363 BS3 23 0.27 9.03 52.5 6.86 782 122 342
BS4 27 0.14 8.10 45 8.60 782 127 395 BS5 24 0.24 8.30 45 8.22 660
123 380 Note: BS--Blended with Diesel BS1-B20, BS2-B80, BS3-B50,
BS4-B40, BS5-B60
Oil Specification
[0058] Specific gravity: 0.916-0.912
[0059] Refractive Index: 1.470-1.473
[0060] Iodine value: 99-108
[0061] Saponification value: 181-189
[0062] Acid value: 4-120
[0063] Titer: 24-28.degree. C.
[0064] Unsaponifiable matter: 3.5%
[0065] Tocopherols average: 400 mg/kg of oil
Fuel Properties
[0066]
2 Property DIESEL Biodiesel (RBOE) Density (gm/cc) 0.82 0.865
Viscosity (Cst) 2.4 3.46 Heat Of Combustion 42.57 45.09 (MJ/Kg)
Flash Point (.degree. C.) 74 182 Fire Point (.degree. C.) 87 194
Copper strip Corrosion No. 3 <No. 1 @ 100 (.degree. C.)
Engine Efficiency
[0067]
3 Specific Fuel Break Thermal Mechanical Indicative Thermal Load
Consumption (kWh) Efficiency (%) Efficiency (%) Efficiency (%) (kW)
Diesel Biodiesel Diesel Biodiesel Diesel Biodiesel Diesel Biodiesel
0 .infin. .infin. 0 0 0 0 20.65 30.22 4 0.556 0.611 15.07 14.01
47.41 37.54 31.77 37.33 7 0.378 0.419 22.17 20.08 62.22 51.27 36.22
40.46 11 0.314 0.333 26.67 25.69 71.26 62.31 37.42 41.23 14 0.292
0.328 28.65 26.07 75.94 67.78 37.73 38.45
[0068] A comparative study of the Complete specification relating
to P03ce04 (an improved process for the preparation of bio-diesel)
and the U.S. Pat. No. 6,015,440 apparently reveals the following
differences.
4 Sl. No U.S. Pat. No. 6,015,440 Bio-diesel Process - Ref No.
P03ce04/CLRI 1. Temperature range of the More than the boiling
point of the alcohol but reaction 70-80.degree. C. less than
215.degree. C. 2. Pressure at 20 psig Atmospheric pressure 3.
Separation alkali using ion Separation of alkali using water
exchange column 4. Top layer approximately 80% More than 80% 5.
Un-reacted methanol removal Un-reacted methanol has separated
immediately by an addition process step of after the reaction by a
specially modified flash recovery system (in a provision built
within on within the reactor separate reactor) 6. Fixed bed/Plug
flow reactor Batch reactor 7. Multiple reactor Single reactor
consists of special provision for excess alcohol recovery 8.
Continuous process Batch process 9. Increased final product The
final product contains only higher fatty acid volume due to
blending of esters. higher fatty acid ester with glyceryl ether.
10. Reaction with isobutylene No such reaction 11. Oxidative
process Base catalysed transesterification 12. Product is Mixture
of Bio- The final product contains higher fatty acid diesel and
Ester glycerol esters. 13. Transesterifying at least a Almost all
portion. portion only 14. This end product of this The end product
is bio-diesel, no mixing with process is a mixture of ester
glycerol. In fact glycerol is obtained as by- and the etherified
glycerol, product which is converted into bio- diesel by blending.
15. Only by mixing the etherified This is a bio-diesel process,
without mixing the glycerol to the esterified oil glycerol, with
all required bio-diesel properties may gives the viscosity and
emission norms similar to the normal diesel reduction. fuel. 16.
Strong acid catalyst process Alkali/base catalyst process 17.
Approximately 80% of the More than 95% in pure form bio-diesel is
in pure form 18. Effect of mixing of etherified No engine
difficulties. No need of any change in crude glycerol's effect in
the the engine needed, no engine block etc. engine is not defined,
shown only the viscosity reduction 19. Low waste process, not More
than 95% conversion. Glycerol formed as separating the 20% crude a
by-product can be used in other industries. glycerol formed. 20.
Formation of 20% glycerol, Glycerol formed as a by-product can be
used in for economical purpose, after other industries. reacting
with isobutylene mixing with the bio-diesel 21. After mixing the
crude The final product after the reaction is similar to glycerol
only, the product diesel fuel gives properties closely resembling
to have of diesel fuel
[0069] In our opinion, the inventive step of the present invention
visa-vis the aforesaid U.S. Patent document, however, essentially
lies in conducting the reaction at a temperature higher than the
boiling point of the alcohol used, besides maintaining the
turbulence (N.sub.Re=4000 or more), that is applicable irrespective
of the type of the reactor used, to enhance the fuel properties of
the resulting product. This step ensures that no blending, as
described in the U.S. Patent document.
[0070] Following are some of the advantages of the present
invention:
[0071] 1. The high temperature with turbulent condition (Reynolds
number more than 4000), reduces the reaction time
significantly.
[0072] 2. The special provision in the reactor enables the
effective recovery of excess alcohol added for the reaction.
[0073] 3. Bubble washing and microfiltration achieved the high
quality of the biodiesel.
[0074] 4. The product is based on renewable source.
[0075] 5. The product can be used as substitute fuel for diesel
engines without any major modification of engines.
[0076] 6. The final product is a substitute fuel for diesel without
blending with other conventional petroleum fuels.
[0077] 7. The products fuel properties and the engine efficiency
are comparable with normal diesel engine fuels.
[0078] 8. The emission characteristics are like those of normal
fuels.
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