DESC:FIELD OF INVENTION:
The present invention relates to the catalyst for transesterification of vegetable oil. More particularly the invention relates to the transesterification catalyst obtained from Bombax ceiba flower. The invention also relates to process for transesterification of oil to produce biodiesel using the catalyst obtained from Bombax ceiba.
BACKGROUND OF THE INVENTION
Biodiesel is generally produced from vegetable oils or animal fats through transesterification with short chain alcohols in presence of catalyst. Trans-esterification reactions are catalyzed by acids, bases and enzymes. The conventional catalyst for this transesterification reaction is homogeneous strong bases (such as alkali metal hydroxides and alkoxides) and homogeneous acids (such as H2SO4, H2SO3). These catalysts give very high yields of alkyl esters, but the reactions are slow, and require temperature typically above 100 oC and more than 3 hours for complete conversion. Acid catalyzed transesterification is more suitable for glycerides that have relatively high free fatty acid contents and more water.
The methanolysis of soyabean oil in presence of 1 mol% H2SO4 with an alcohol/oil molar ratio 30:1 was studied. At the reaction temperature of 65 oC, the conversion of vegetable oil was observed to be completed in 20 hrs, while butanolysis at 117 oC and ethanolysis at 78 oC using the same quantities of catalyst and alcohol, took 3 hrs and 18 hrs respectively.
Bases used for transesterification include NaOH, KOH, carbonates and alkoxides such as sodium methoxide, sodium ethoxide, sodium propoxide and sodium butoxide. The base catalyzed transesterification of vegetable oil proceeds faster than that catalyzed by the same amount of acidic catalyst. Moreover, the base catalysts are less corrosive than acidic compounds. Due to such reasons industrial processes usually prefer base catalyst such as metal alkoxide and hydroxides as well as sodium or potassium carbonates.
Enzyme or lipases are naturally occurring substances. Due to their ready availability and the ease with which they can be handled, enzymes have been widely used in organic chemistry. They don’t require any co-enzyme, are reasonably stable and often tolerate organic solvents. Their potential for regioselective and especially for enantioselective synthesis makes them valuable tools. They are widely employed to catalyze hydrolysis, alcoholysis, esterification and trans-esterification process during biodiesel production. Though enzyme base transesterification can be carried out at moderate temperature with high yields, still this method is not used in industry due to high enzyme cost, and the problems related to its deactivation caused by feed impurities.
Although chemical transesterification using an alkaline catalysis process gives high conversion levels of triglycerides to their corresponding methyl ester in short reaction times, the reaction has several limitations, like being energy intensive, difficult recovery of glycerol, required removal of catalyst from the product, need of treatment of alkaline waste water and interference of free fatty acid and water in the reaction. In order to minimize the homogeneous process problems and the present day high production cost of biodiesel, heterogeneous catalyst are being explored for the transesterification reaction of vegetable oil to produce biodiesel. Unlike homogeneous catalysts, heterogeneous catalysts are environmentally benign and could be operated in continuous processes. Heterogeneous catalysts are advantageous for biodiesel production because of their reusability and thus more eco-friendly in nature. Catalysts greatly simplify the post treatment of the products. They can be easily separated from the system at the end of the reaction and could also be reused. Beside this, the use of heterogeneous catalyst doesn’t produce soaps through free fatty acid neutralization or triglyceride saponification. They can be designed to give higher activity, selectivity, and longer catalyst lifetimes. A large number of acid and base heterogeneous catalysts have been reported in the literature.
Peng et al. studied SiO2/TiO2-SiO2 as a solid catalyst for the production of biodiesel from low cost feedstock (50 % oleicacid + 50 % refined cotton seed oil) with high fatty acid in reactor at 200 oC with methanol: oil at molar ratio of 9:1, 3 wt. % catalyst conc. Reaction time 70 min FAME obtained is 92 %.
Deka et al. reported a novel catalyst derived from the trunk of Musa balbisiana colla (one variety of banana plant) in to biodiesel industry and showed that 96 % of Theventia peruviana seed oil was converted to biodiesel at 32 oC in 3 h using catalyst (20 wt % of oil).The catalyst is heterogeneous and easily prepared from the waste of post – harvest banana plants.
Boey et al. utilized waste cockle shell (Anandara granosa) as a source of calcium oxide in catalyzing the trans-esterification of palm oil to biodiesel and reported that the yield of above 97 % was achieved in reaction time 3 h.
Chacraborty et al. investigated the feasibility of converting waste rohu fish (Labeo rohita) scale into a high performance, reusable, low–cost heterogeneous catalyst for synthesis of bio diesel from soyabean oil. Response surface methodology was employed to determine the optimal parametric conditions viz. methanol/oil molar ratio, 6.27:1, calcinations temperature 997.42 oC and catalyst concentration, 1.01 wt % of oil. A maximum FAME yield of 97.73% was reported.
Despite several catalysts obtained from varied sources, the need of a transesterification catalyst still persists which can catalyze the reaction in an efficient manner consuming lesser time and resulting a high quantity and quality of biodiesel.
SUMMARY OF THE INVENTION:
The present invention relates to the high efficiency of the heterogeneous catalyst derived from Bombax ceiba flower in the conversion of seed oil to biodiesel has been established; using this catalyst. Conversion of 95 wt % of oil to biodiesel at room temperature (32 oC) in 1 h could be achieved. The catalyst is thermally stable. The catalyst has very rich commercial prospects, especially in biodiesel industries, as the catalyst can be prepared at nominal cost from the waste of Bombax ceiba flowers. The plant is available throughout India. The catalyst is biodegradable and environmentally acceptable.
Accordingly, the present invention provides a catalyst for transesterification of oil to prepare biodiesel, prepared by the process comprising the steps of:
(a) Air drying flowers of Bombax ceiba;
(b) Burning the dried flowers to obtain ash;
(c) Cooling the ash to bring to an ambient temperature to obtain catalyst.

In an embodiment, the present invention further comprises drying the catalyst in oven at 100 to 120 °C to remove moisture.

In another embodiment of the present invention, the air drying of the flower is done at a temperature of 25 to 32 °C, for a period of 15 to 20 days.

In still another embodiment of the present invention, the flowers of Bombax ceiba are mature flowers.

In still another embodiment of the present invention, the catalyst comprises Ni in the range of 0.73-0.77 ppm, Fe in the range of 12.44-15.44 ppm, Mg in the range of 361.15-368.15 ppm, Cu in the range of 1.02 -1.60 ppm, Pb in the range of 18.91-19.91 ppm, Co in the range of 01.69-01.79 ppm, Mn in the range of 0.96-1.05 ppm, Na+ in the range of 0.098-0.109 ppm and K+ in the range of 1.090-1.590 ppm.

In still another embodiment of the present invention, a process for transesterification of vegetable oil, comprising: contacting a catalyst comprising ash of flowers of Bombax ceiba with a vegetable oil in the presence of a solvent.

In still another embodiment of the present invention, the vegetable oil is selected from the group comprising of pummelo, pumpkin, ridge gourd, sponge guard, bitter gourd, radish, sunflower, yellow oleander, pink oleander, white oleander and mixtures thereof.

In yet another embodiment of the present invention, the alcohol is selected from the group consisting of methanol and ethanol.

In yet another embodiment of the present invention, the contacting is carried out for a period of
1 Hours.

In yet another embodiment of the present invention, the contacting step is carried at a temperature of 32 °C.

In yet another embodiment of the present invention, the ratio of the catalyst to the oil is in a range of 1:100 to 20:100.

In yet another embodiment of the present invention, the preferred ratio of the catalyst to oil is 20:100

In another embodiment of the present invention, the ratio of the oil to the alcohol is in a range of 1:2 to 1:20.

In an embodiment of the present invention, the preferred ratio of oil to alcohol is 1:10.

In further another embodiment of the present invention, the catalyst is reusable in the process.

In an embodiment of the present invention, the catalyst is reused by the process comprising the steps of:
a) Drying the used catalyst in hot air oven at 110-120 oC for 2-3 h; and
b) Cooling to ambient temperature inside desiccators to obtain the catalyst for reuse.

In yet another embodiment of the present invention, the catalyst provides 94.7 % conversion by weight in 1 h, 94.0 % conversion by weight in 1.5 h and 93.7% conversion by weight in 2h, in the in first reuse.

In further another embodiment of the present invention, a process for the preparation of a transesterification catalyst, comprising the steps of:
(a) Collecting mature flowers of Bombax ceiba;
(b) Air drying the collected flowers;
(c) Burning the dried flowers to obtain ash;
(d) Cooling the ash to bring to an ambient temperature; and
(e) Optionally, drying the ash in an oven at a temperature of 100-120°C to obtain the catalyst.

In an embodiment of the present invention, the air drying is performed for a period ranging from 15 to 20 days.

In an embodiment of the present invention, the burning of the dried flowers is performed for a period ranging from ½ to 1 hour.

BRIEF DESCRIPTION OF DRAWINGS:
Fig 1: Pictures of different stages of the preparation of the catalyst and yellow oleander seeds.
Fig 2: Thermo gravimetric analysis graph of Bombax ceiba data;
Fig 3: BET plot graph;
Fig 4: Particle size determination;
Fig 5: X-Ray Fluorescence graph of Bombax ceiba catalyst;
Fig 6: X-Ray Diffraction graph of Bombax ceiba catalyst;
Fig 7(A): IR spectra of yellow oleander seed oil;
Fig 7(B): IR spectra of the methyl ester from yellow oleander seed oil;
Fig 8(A): H1-NMR spectrum of the yellow oleander seed oil;
Fig 8(B): H1 NMR spectrum of the methyl ester from yellow oleander seed oil;
Fig 9(A): 13CNMR spectrum of yellow oleander seed oil;
Fig 9(B): 13 C NMR spectrum of the methyl ester from yellow oleander seed oil;
Fig 10: IR Spectrum of Pummelo oil;
Fig 11: IR Spectrum of Pummelo FAME;
Fig 12: H1 NMR spectrum of Pummelo FAME;
Fig 13: 13CNMR spectrum of Pummelo FAME;
Fig 14: IR spectrum of soybean oil;
Fig 15: IR spectrum of soybean FAME;
Fig 16: The main signals present in 1H-NMR spectrum of ridge gourd FAME and their assignments.

DESCRIPTION OF THE INVENTION
The present invention discloses an environment friendly highly active catalyst obtained from Red cotton plants capable of catalyzing transesterification of vegetable oil with solvent in highly efficient manner in lesser time for major production of biodiesel.
Stems of the red cotton have already been explored for preparation of match sticks in Matches factory. The use of red cotton flowers as raw material for catalyst has showed a new economical method of producing the biodiesel.
The catalyst has been developed from floral part of red cotton tree (Bombax Ceiba). These plants are available everywhere in India and majorly available in Assam. Red cotton tree grows to an average of 20 meters, with old trees up to 60 meters in wet tropical weather. The trunk and limb bear numerous conical spines particularly when young, but get eroded when older. The leaves are palmate with about 6 leaflets radiating from a central point, an average of 7~10 centimeters wide, 13~15 centimeters in length. The leaf's long flexible petiole is up to 20 cm long.
Cup-shaped flowers solitary or clustered, axillary or sub-terminal, fascicles at or near the ends of the branches, when the tree is bare of leaves, an average of 7~11 centimeters wide, 14 centimeters in width, petals up to 12 centimeters in length, calyx is cup-shaped usually 3 lobed, an average of 3~5 centimeters in diameter. Staminal tube is short, more than 60 in 5 bundles. Stigma is light red, up to nine centimeters in length, ovary is pink, 1.5~2 centimeters in length, with the skin of the ovary covered in white silky hair at 1mm long. Seeds are numerous, long, ovoid, black or gray in colour and packed in white cotton.
The fruit, which reaches an average of 13 centimeters in length, is light-green in color in immature fruits, brown in mature fruits.
The Bombax ceiba plant is available in abundance in India. As such the catalyst can be prepared at very minimal cost. The yellow oleander plant is also available in abundance.
Kingdom: Plantae; Order: Malvales; Family: Malvaceae; Genus: Bombax; Species: B. ceiba; Binomial name: Bombax ceiba L.
The commercial production of diesel by transesterification of seed oil using heterogeneous catalyst prepared from waste floral part of Bombax ceiba plant would be available at very low price.
The catalyst is derived from the flowers of red cotton plants (Bombax ceiba), and it is heterogeneous. Transesterification of seed oil with methanol at room temperature (32 oC), is carried out successfully with high yield in the presence of 20 wt% of the catalyst and short reaction time. The red cotton flowers have been considered as waste and have not been unused till date. Therefore, use of this waste biomass will benefit the environment and society as well.
One aspect of the present invention is the process of the preparation of the catalyst from the flowers of the Bombax ceiba. The flowers of Bombax ceiba, which are matured and lie as waste material beneath the tree and air dried for several days, are collected from the plant sides. The dry material was allowed to burn normally. Burning generally completes within half an hour. Later the product was cooled down to bring it to ambient temperature. The ashes are kept inside oven at temperature 100-120 oC to remove the moisture. The ashes were then preserved in air tight plastic container. These obtained ashes are used as catalyst.
The chemical composition of the catalyst was estimated by chemical analysis, Atomic absorption spectroscopy and Flame photometry. The major components of the catalyst are Na+, K+, CO3- and Cl- along with other metals like Al, V, Cr, Mn, Fe, Cu, Zn, Cd, Ni, Pb etc. in ppm level. Apart from the composition, the catalyst has also been characterized in terms of BET (Brunauer–Emmett–Teller) surface area, pore size and pore volume.
Another aspect of the invention provides the efficient transesterification reaction of the vegetable oil to biodiesel. The vegetable oil can be selected from the group of oleander oil, soyabean oil etc. In accordance with one of the embodiments of the invention, the transesterification of the seed oil obtained from yellow oleander i.e. Thevetia peruvaiana was carried out using a solvent in presence of derived catalyst. The yield of biodiesel from yellow oleander seeds oil was found to be more than 95 % at room temperature (32 oC) within 1 hour.
On analysis of the typical 1H NMR spectra of Thevetia peruvaiana seeds oil and biodiesel the major differences observed is the disappearance of the signals representing protons of glycerol moiety of the glycerides at d 4.16 (dd), 4.28 (dd) and 5.30-5.34 (m) and singlet signal is appeared at d 3.69 ppm, which is due to the methoxy protons of ester function of conversion of the yellow oleander seed oil to biodiesel.
The signal obtained at d 62.00 and 68.79m in 13C NMR spectrum of the Thevetia Peruvian seeds oil revealed the presence of glyceryl carbon in triglyceride molecules, which disappeared in case of diesel obtained after trans-esterification. Also the appearance of one new signal at d 56.41ppm due to the methoxy carbon is indicative enough for desired transformation.
Similarly, In IR–spectrum a sharp signal can be observed at 1747.51 cm-1 in case of oil. However, signal obtained at d 1743.65 cm-1 in case of biodiesel are indicative of strong absorptions by respective carbonyl stretching frequencies.
The conversion of oil to corresponding methyl ester has also been established through TLC.
Various oils which may be used to prepare biodiesel:
Table 1:
Local Name English Name Botanical Name
Robab Tenga Pummelo Citrus maxima
Rongalau Pumpkin Cucurbita moschata
Jika Ridge gourd Luffa acutangula
Bhol Sponge gaurd L. cylindrica
Tita Kerela Bitter Gourd Momordica Charantia L
Mula Radish R. sativum L
Surjyamukhi Sunflower Helianthus annuus
Haldhia Karabi Yellow oleander
Thevvetia peruviana
Gulopia Karabi Pink oleander
Boga karabi White oleander

The catalyst obtained from the flowers of Bombax Ceiba has been found to be thermally stable, reusable. Reusability of the catalyst has been established through experimentation. The used catalyst was dried in hot air oven at 110120 oC for 2-3 h followed by cooling to ambient temperature inside desiccators. Using this catalyst, conversion of more than 95 wt % of oil to biodiesel at room temperature (32 oC) in 1 h could be achieved.
In another embodiment of the present invention the catalyst has been found to show better catalytic activity when it has been activated by pre heating. Another aspect of the invention discloses the better quality of the biodiesel prepared using this novel catalyst. The product Yellow oleander methyl ester (YOME) obtained after transesterification of Yellow Oleander seed oil has been evaluated for the diesel characteristics.
Therefore the catalyst prepared has very rich commercial prospects, especially in biodiesel industries. Besides offering advantages like being biodegradable and environmentally acceptable, this catalyst can also be prepared in a very cost effective manner from the waste Bombax ceiba flowers.
Example 1:
Preparation of catalyst:
Step 1: Open air natural burning:
Catalyst is prepared from the flowers of Bombax ceiba. Matured and naturally fallen flowers are collected and air dried (25 to 32 oC) for 14 to 15 days. The dry material is burnt in open air and cooled naturally. The time requirement for complete burning process is about 30 min. The ashes are then preserved in air tight plastic container.

Table 2: % Yield of catalyst from Bombax ceiba flower
No. of Sets Weight of flower (g) Weight of catalyst (g) % yield
Set -1 100.54 15.05 14.96
Set-2 103.98 16.20 15.57
Set-3 102.31 15.97 15.60
Average 15.37

Step 2: Burning inside muffle furnace under controlled temperature:
Catalyst is prepared from the flowers of Bombax ceiba, matured and naturally fallen flowers are collected and air dried (25 to 32 oC) for 14 to 15 days. The dry material is burnt inside muffle furnace under controlled temperature at 350 oC ± 5 oC in about 1h and cooled naturally.
Table 3: Variations in two different preparation procedures:
No of Sets Weight of flower (g) Weight of catalyst (g) % yield
Set -1 13.65 2.00 14.65
Set-2 12.97 1.81 13.98
Set-3 13.00 1.86 14.32
Average 14.21
From the above two table; no such large variation can be observed in % Yield of the catalyst. The important thing is the preservation of the catalyst. We should preserve the catalyst inside air tight plastic container. The ashes are kept inside oven at temperature 100 oC-120 oC to remove the moisture before use.
Example 2:
CHARACTERIZATION OF THE CATALYST:
Thermal stability and BET surface area of the catalyst:
To observe the thermal stability of the catalyst, Thermal Gravimetric Analysis (TGA) measurement was conducted. The TGA of the catalyst is shown in Fig: 2. It shows that the catalyst start losing weight on heating at 200 oC, from 200 oC to about 400 oC the catalyst is stable indicated by near constant weight in this range of temperature. Beyond 400 oC, the catalyst starts losing weight again albeit at slow rate. Near 700 oC, catalyst continues to lose weight at somewhat increasing rate.
The loss of weight in the early part of the heating i.e. to about 400 oC is due to the loss of physically absorbed water from the surface of the catalyst. Loss of the weight above 400 oC may be due to the slow loss of water of crystallization as no chemical change is expected in this range of temperature. Loss of weight due to the chemical decomposition is expected at a temperature beyond 700 oC.
From the TGA graph it is cleared that the catalyst is thermally very stable. Only 0.5% weight loss is observed throughout the operation.
BET Surface Area, Pore Volume, Pore Size:
BET surface area, pore volume, pore size is also reported in Table 4.
Table 4: BET surface area, pour volume and pour size-
Catalyst from BET surface area
(m2/g) Pore volume
(cm3/g) Pore size
(A0)
Bombax ceiba 9.614 0.018918 3.047

Particle size determination:
Particle size in nano meter, intensity and width are determined by diffraction light scattering instrument, Model no.: Malvern Zetasizer Nano ZS 90.
Table 5:
Peak Particle Size (d. nm) % Intensity Width (d. nm)
Peak 1 409.3 84.1 41.73
Peak 2 100.6 15.9 6.913
Peak 3 0.000 0.0 0.000

Example 3:
Chemical composition of the catalyst obtained from flowers of Bombax ceiba:
Step 1: Catalyst obtained from Bombax ceiba flower collected from Dhubri district, Assam:
The presence of the following metals is confirmed by Atomic absorption Spectroscopy (ASS):
Table 6: ASS –Data for Bombax ceiba extract:
Sample Ni
(ppm) Cd
(ppm) Cr
(ppm) Fe
(ppm) Mg
(ppm) Cu
(ppm) Pb
(ppm) Co
(ppm) Mn
(ppm)
Bombax ceiba 0.77 0.0 0.0 12.44 361.15 1.02 19.91 01.79 0.96

Flame photometry:
The amount of Na+ and K- were determined with Flame photometer.
Na+ 0.098 ppm
K+ 1.090 ppm

Catalyst obtained from Bombax ceiba flower collected from Kamrup district, Assam:
The presence of the following metals is confirmed by ASS.
Table 7: ASS –Data for Bombax ceiba extract-
Sample Ni
(ppm) Cd
(ppm) Cr
(ppm) Fe
(ppm) Mg
(ppm) Cu
(ppm) Pb
(ppm) Co
(ppm) Mn
(ppm)
Bombax ceiba 0.73 0.0 0.0 15.44 368.15 1.60 18.91 01.69 1.05

Flame photometry:
The amount of Na+ and K- were determined with Flame photometer.
Na+ 0.109 ppm
K+ 1.590 ppm

Consistency in composition of catalyst based on different region & geography:
From the ASS and the Flame photometry in the above examples no such major variation can be attributed. The small increase or decrease in the measured value is/are within the repeatability and reproducibility limit.
Example 4:
Preparation of biodiesel from various oils, particularly, the various process parameters, such as range/ratio of catalyst and other reactants used in the process.
Table 8: Determination of the suitable oil to catalyst ratio for the transesterification of the seed oil to biodiesel
Oil : Catalyst (w/w) Yield of biodiesel (%) Oil : Methanol (w/vol) Time
Highest yield for 100:1 oil to catalyst ratio
100:1 85.0 1:10 1hrs
87.0 2hrs
90.0 3hrs
90.0 4hrs
Highest yield for 100:5 oil to catalyst ratio
100:5 88.0 1:10 1hrs
88.5 2hrs
91.0 3hrs
91.0 4hrs
Highest yield for 100:10 oil to catalyst ratio
100:10 90.0 1:10 1hrs
91.0 2hrs
91.5 3hrs
92.0 4hrs
Highest yield for 100:20 oil to catalyst ratio
100:20 95.01 1:10 1hrs
95.08 2hrs
97.0 3hrs
97.0 4hrs

From the above table it is confirmed that 20% weight of the catalyst is suitable for the conversion of seed oil to biodiesel.
Table 9: Determination of the suitable oil to methanol (solvent) ratio for the transesterification of the seed oil to biodiesel
Effect of methanol in the yield of biodiesel
Oil : Catalyst (w/w) Time Oil : Methanol (w/vol) Yield of biodiesel (%)
100:20 1 hrs 1:2 85
1:5 90
1:10 95
1:15 95
1:20 95

The less solvent shows less yield %, excess solvent has no effect on the yield. Therefore the suitable ratio of oil to solvent is 1:10.
Trans-esterification of yellow oleander seed oil to biodiesel:
Trans-esterification of seed oil obtained from Thevetia peruviana to biodiesel (yellow oleander methyl ester) was carried out using methanol (1:10) as the solvent in presence of the catalyst (20 wt %) derived from red cotton flowers (Bombax ceiba). The yield of biodiesel was 95% at 32oC within 1 hour.
The conversion of oil to corresponding methyl ester can also be confirmed from TLC.
Table 10: Assignments of IR bands of yellow oleander seed oil
? (cm-1) Assignment
3008.87
1747.51
1454.33 and 1377.17
1185.00 C – H stretching in methyl/methylene
C=O stretching (in esters)
C – H deformation
C – O stretching in esters
Table 11 : Assignments of IR bands of yellow oleander FAME
? (cm-1) Assignment
1743.65
1654.92
1246.02, 1195.87, 1095.57
721.38
2924.09, 2854.65
3005.10 C=O stretching vibration
C=C stretching vibration
C-O-C stretching vibration
-CH2 skeletal vibration
C-H stretching vibration
=C-H stretching and deformation

Typical 1H NMR spectra of the Thevetia peruviana seed oil and biodiesel are presented in Fig: 8A and Fig: 8B
In the spectra it can be seen that the major differences between 1H NMR spectra of the oil and the biodiesel is the disappearance of the signals representing protons of glycerol moiety of the glycerides at d 4.16 (ppm), 4.28 (ppm) and 5.30-5.34(m) and the appearance of a singlet signal at d 3.69 ppm. Due to the methoxy protons, the conversion of the yellow oleander seed oil to biodiesel.
The signals obtained at d 62.00 and 68.79 in 13C NMR spectrum of the Thevetia peruviana seeds oil [Fig: 9(A)] revealed the presence of glyceryl carbon in triglyceride molecules, which disappear in case of diesel (after trans-esterification). Appearance of one new signal at d 56.41ppm [Fig: 9 (B)] due to the methoxy carbon is indicative enough for desired transformation
Trans-esterification of pummelo seed oil to biodiesel:
Trans-esterification of seed oil obtained from pummelo to biodiesel was carried out using methanol as the solvent in presence of the catalyst derived from red cotton flowers (Bombax ceiba). The yield of biodiesel was 95.5 % at room temperature (32oC) within 1 hour. Typical IR, 1H NMR and 13C NMR spectra of the pummelo seed oil and biodiesel are presented:
Table 12: Assignments of IR bands of Pummelo oil
? (cm-1) Assignment
3009.1
1746.2
1462.2 and 1381.1
1238.9 C – H stretching in methyl/methylene
C=O stretching (in esters)
C – H deformation
C – O stretching in esters
Table 13: Assignments of IR bands of Pummelo FAME
? (cm-1) Assignment
1743
1660
1248, 1172, 1023
723
2926, 2842
3018 C=O stretching vibration
C=C stretching vibration
C-O-C stretching vibration
CH2 skeletal vibration
C-H stretching vibration
=C-H stretching and deformation

The main signals present in 1H-NMR spectrum of pummelo FAME and their assignments
d (ppm) Assignment
3.62
5.3
1.1-2.4
0.79-0.82 -OMe
-CH=CH-
-CH2-
-CH3 (Terminal)
Trans-esterification of soybean oil to biodiesel:
Trans-esterification of seed oil obtained from soybean to biodiesel was carried out using methanol as the solvent in presence of the catalyst derived from red cotton flowers (Bombax ceiba). The yield of biodiesel was 96.0 % at room temperature (32oC) within 1 hour. Typical IR, 1H NMR and 13C NMR spectra of the soybean seed oil and biodiesel are presented—
The main signals present in 1H-NMR spectrum of ridge gourd FAME and their assignments.
d (ppm) Assignment
3.61
5.3
1.1-2.34
0.79-0.82 -OMe
-CH=CH-
-CH2-
-CH3 (Terminal)

Example 6:
Recovery of the catalyst after the completion of process for preparation of biodiesel:
The catalyst is separated from the reaction mixture by filtration. The residue was washed first with methanol and then petroleum ether with several times and dried in hot air oven at 110-120 oC for 2-3 hrs followed by cooling to ambient temperature inside desiccators.
Activation of the catalyst:
The catalyst was activated by heating by heating them at 350 ±5 oC in a programmable muffle furnace. About 15 – 20 g of the used catalyst were taken in platinum crucible (preheated and weighted) and then heated in the muffle furnace to 350 ±5 oC for 1h. after heating was completed, the catalyst was allowed to cool to room temperature inside a desiccators, and preserved until the use.
Example 7:
Reusability of the catalyst:
The catalyst is reusable. The used catalyst was dried in hot air oven at 110-120 oC for 2-3 h followed by cooling to ambient temperature inside desiccators. In first time reuse, 94.7% conversion was found by weight in 1h. 94.0 %was obtained in 1 and 93.7% was obtained in 2 h.
Table 14: Reusability of the best catalyst (from Bombax ceiba flowers) in transesterification of Thevetia Peruviana seed oil
Catalyst (20 wt% of oil) Reaction time (h) Yield (wt %)
1st use 1 95.0
1st reuse 1 94.7
2nd reuse 1
94.0
3rd reuse 2 93.7

Reaction conditions: Thevetia peruviana seed oil 2 g; methanol 20ml; reaction temperature 320C.
Example 8:
Comparison with other reported catalyst:
Table 15: Some reported catalysts are-
Name of the catalyst Temperature ( oC) Time (h) Yield (%)
H2SO4 65 20 --
ZnO,Hß-Zeolite, and Montmorillonite K-10 120 24 83
La (La/zeolite beta) 120 24 48.9
SiO2/TiO2-SiO2 200 1.16 92
Calcium oxide › 60 3 97
waste rohu fish 997.43 -- 97.7
Musa balbisiana Colla 32 3 96
K2CO3 32 2.0 94
Na2CO3 32 3.5 93
NaOEt 32 28.0 93

Example 9:
The YOME product was blended with BS-III/ Euro-IV petro diesel in the following proportion:
Table 16: Blending of YOME product with Petro diesel in different proportions:
SL. No Sample YOME Petro- diesel
1 B-05 5% 95%
2 B-10 10% 90%
3 B-15 15% 85%
4 B-20 20% 80%
The fuel properties of different YOME Samples have been analyzed. A comparison has also been made with Indian Automotive Diesel fuel graded Bharat Stage-III (BS-III/EURO-III) and with the biodiesel standards ASTM D-6751 and EN 14214. The results are tabulated below.
Table 17: Comparison of the properties of blend of petro and bio-diesel mix, with manufacturing spec of BS-II/EURO-III:
Sl. No. Characteristics Test Method Specification Test Results
BS-III /Euro-III B-05 B-10 B-15 B-20 YOME
1 Acidityof Inorganic Acids in mg KOH/g P-2 Max=0.0 0.0 0.00. 0.0 0.0 0.0 0.0
2 Acidity-Total in KOH/mg D-664 Max=0.5mg 0.05 0.051 0.053 0.055 0.056 0.057
3 Ash content D-482 Max=0.01% (m) 0.005 0.007 0.008 0.0089 0.0097 0.013
4 Carbon Residue (Rams bottom) on 10% residue D-524 Max=0.30% (m) 0.04 0.06 0.07 0.09 0.1 0.4
5 Cetane Number D-613 Min=48 (Assam crude) 48.5 48.7 49.0 49.2 49.4 61.5
6 Cetane Index D-976 Min=46 46.00 46.35 46.42 46.53 46.55 62.9
7 Distillation(V/V) D-86
IBP 138.5 144.6 144.1 140.9 142.1 250
5% 163.9 165.1 166.6 166.2 167.7
10% 176.5 179.5 181.6 187.9 187.9
50% 269.6 271.6 276.4 285.1 284.9
90% 343.7 343.0 343.5 344.3 343.3
95% 359.3 360.2 359.1 357.8 356.8
FBP 374.5 371.7 371.8 372.3 367.1 360
Rec@360°C Min=95 vol% 95.2 95.3 95.5 95.7 95.8 98.5
8 Flashpoint(Abel) P-20 Min 35.0 CEL 43.0 45.0 46.0 46.0 47.0 175.0
9 Kinematic Viscosity @ 40°C D-2270 2.000-4.500cSt
2.61 2.82 3.04 3.22 3.45 4.33
10 Density @15 °C (for ASSAM CRUDE) D-1298
820.0-855.0Kg/m3 847.1 847.3 849.3 852.8 853.8 875.0
11 Total Sulphur IP-336 BS-III=350 & BS-IV=50 244 232 220 207 195 0
12 Pour Point(winter) D-97 Max=+3CEL 3 3 3 3 3 3
13
Cold filter-plugging point(summer) D-6371 Max=18CEL 6 6 6 6 6 6
14 Water content Karl fisher Max=200mg/kg 135 137 142 147 150 170
15 Total contamination DIN 51419 Max=24.0 mg/kg 18 17.5 17.01 16.51 16.03 15.0
16 Oxidation Stability D-7422 Max=25g/m3 9.9 10.3 12.3 13.1 14.0 17.0
17 Polycyclic Aromatic Hydrocarbon (PAH) 1P-391
Max11.0% (m) 2.7 3.825 4.95 6.075 7.2 28.9
18 Lubricity, corrosion scar wear diameter (Rear@-60°C) D6079 Max 460.0 µm 415 393 375 351 323 260

From the above table it is evident that the parameters like Acidity, Ash content, carbon residue, Cetane Index, Dist, Rec@360°C, Flash point, kinematic Viscosity@40°C, Density@15°C, Total sulphur, Pour point, cold filter plugging point, water content, Total contamination, oxidation stability [ASTM D-7422], poly-aromatic hydrocarbon [IP-391] and lubricity, corrected scar wear diameter (WSD) @ 60 °C [ASTM D-6079] as determined by ASTM, IP, BIS, DIN-methods get improved when YOME has been blended with Petro-diesel.
Improvement in fuel property by blending of YOME with petro-diesel is also done without changing the engine arrangement.
Advantages of Bombax Ceiba catalyst:
• The high efficiency of heterogeneous catalyst derived from Bombax ceiba flower in the conversion of seed oil to biodiesel.
• Conversion of 95.0 wt % of oil to biodiesel at room temperature (320C) in 1 hour.
• The thermal stability, reusability and better catalytic activity when activated by heating in the range of 4000C to 7000C. From the TGA graph it is cleared that the catalyst is thermally very stable. Only 0.5% weight loss is observed throughout the operation.
• The catalyst has very rich commercial prospects, especially in biodiesel industries, as the catalyst can be prepared at nominal cost from Bombax Ceiba flowers, which is otherwise a waste material.
• As the catalyst is green catalyst, it is biodegradable and environmentally acceptable. Using this novel catalyst the Transesterification of yellow oleander seed oil is carried out and the product obtained is then evaluated for their diesel characteristics and then mixed with petro diesel.
• The catalyst is easily separable.
,CLAIMS:We Claim:
1. A catalyst for trans-esterification of oil to prepare biodiesel, prepared by the process comprising the steps of:
i. Air drying flowers of Bombax ceiba;
ii. Burning the dried flowers to obtain ash;
iii. Cooling the ash to bring to an ambient temperature to obtain catalyst.

2. The catalyst according to claim 1, further comprising drying the catalyst in oven at 100 to 120 °C to remove moisture.

3. The catalyst according to claim 1, wherein the air drying is done at a temperature of 25 to 32 °C, for a period of 15 to 20 days.

4. The catalyst according to claim 1, wherein the flowers of Bombax ceiba are mature flowers.

5. The catalyst according to claim 1, wherein the catalyst comprises Ni in the range of 0.73-0.77 ppm, Fe in the range of 12.44-15.44 ppm, Mg in the range of 361.15-368.15 ppm, Cu in the range of 1.02 -1.60 ppm, Pb in the range of 18.91-19.91 ppm, Co in the range of 01.69-01.79 ppm, Mn in the range of 0.96-1.05 ppm, Na+ in the range of 0.098-0.109 ppm and K+ in the range of 1.090-1.590 ppm.

6. A process for transesterification of vegetable oil, comprising: contacting a catalyst comprising ash of flowers of Bombex ceiba with a vegetable oil in the presence of a solvent.

7. The process according to claim 6, wherein the vegetable oil is selected from the group comprising of pummelo, pumpkin, ridge gourd, sponge guard, bitter gourd, radish, sunflower, yellow oleander, pink oleander, white oleander and mixtures thereof.

8. The process according to claim 6, wherein the alcohol is selected from the group consisting of methanol and ethanol.

9. The process according to claim 6, wherein the contacting is carried out for a period of between 1 hour.

10. The process according to claim 6, wherein the contacting step is carried at a temperature of 32oC.

11. The process according to claim 6, wherein the ratio of the catalyst to the oil is in a range of 1:100 to 20:100.

12. The process according to claim 11, wherein the preferred ratio of the catalyst to oil is 20:100.

13. The process according to claim 6, wherein the ratio of the oil to the alcohol is in a range of 1:2 to 1:20.

14. The process according to claim 13, wherein the preferred ratio of oil to alcohol is 1:10.

15. The process according to claim 6, wherein the catalyst is reusable in the process.

16. The process according to claim 6, wherein the catalyst is reused by the process comprising the steps of:
i. drying the used catalyst in hot air oven at 110-120 oC for 2-3 h; and
ii. cooling to ambient temperature inside desiccators to obtain the catalyst for reuse.

17. The process according to claim 6, wherein the catalyst provides, 94.7% conversion by weight in 1h, 94.0 % conversion by weight in 1.5 h and 93.7% conversion by weight in 2h, in the in first reuse.

18. A process for the preparation of a trans esterification catalyst, comprising the steps of:
(a) collecting mature flowers of Bombax ceiba;
(b) air drying the collected flowers;
(c) burning the dried flowers to obtain ash;
(d) cooling the ash to bring to an ambient temperature; and
(e) optionally drying the ash in an oven at a temperature of 100-120°C to obtain the catalyst.

19. The process as claimed in claim 18, wherein the air drying is performed for a period ranging from 15 to20 days

20. The process as claimed in claim 18, wherein the burning of the dried flowers is performed for a period ranging from ½ to 1 hour.