The cetane number is seldom an issue because all of the common fatty acid esters have cetane numbers near or above It is unlikely that an individual producer will ever run cetane tests on-site because the equipment is extremely expensive. The requirement is the cetane number has to be above The water and sediment test is a measure of cleanliness of the fuel. It is particularly important because water can react with the esters, making free fatty acids, and can support microbial growth in storage tanks.
Water is usually kept out of the production process by removing it from the feedstocks. However, some water may be formed during the process by the reaction of the sodium or potassium hydroxide catalyst with alcohol. If free fatty acids are present, water will be formed when they react to either biodiesel or soap.
Finally, water is deliberately added during the washing process to remove contaminants from the biodiesel. This washing process should be followed by a drying process to ensure the final product will meet the standard. Sediments may plug fuel filters and may contribute to the formation of deposits on fuel injectors and other engine damage. Sediment levels in biodiesel may increase over time as the fuel degrades during extended storage.
The production QC lab should be equipped to perform this test on a routine basis. The carbon residue is a measure of how much residual carbon remains after combustion. The test basically involves heating the fuel to a high temperature in the absence of oxygen.
Most of the fuel will vaporize and be driven off, but a portion may decompose and pyrolyze to hard carbonaceous deposits. This is particularly important in diesel engines because of the possibility of carbon residues clogging the fuel injectors. The most common cause of excess carbon residues is an excessive level of total glycerin.
Free glycerol is the glycerol present as molecular glycerol in the fuel. Free glycerol results from incomplete separation of the ester and glycerol products after the transesterification reaction. This can be a result of imperfect water washing or other approaches that do not effectively separate the glycerol from the biodiesel.
The free glycerol can be a source of carbon deposits in the engine because of incomplete combustion. The Jatropha seed was purchased from local market in Desie for the extraction of oil using hexane as solvent. The equipments used during the experimentations are Glass reactor equipped with mechanical stirrer, thermostat, and condenser, Centrifuge, Rotary Evaporator Hydrometer, Vibro viscometer, Bomb Calorimeter, Bunsen burner, conical flask, balance and burette.
Finally, the clean kernels were grounded by using Fritsch cutting mill to 2. The extraction method used was known as cold extraction. The grounded seed was mixed with the proper amount of solvent, hexane, in a batch vessel for 3 days with occasional agitation. During these days, the hexane extracts oil from the grounded kernel. Supernatant solution was collected which is the mixture of extracted oil and hexane after it is separated from the kernel cake by decantation.
Since some amount of suspension is available within the supernatant solution, filtration is employed with the help of filter paper to remove all the suspension from the extracted oil. After the separation was completed, all of the remaining solution was transferred to rotary evaporator and the mixture was distilled to separate hexane from the extracted oil.
The extracted crude Jatropha oil contains phosphatides, gums and other complex compounds which can promote hydrolysis increase in free fatty acid of vegetable oil during storage.
During transesterification process, these compounds can also interfere. Therefore these compounds are removed by acid degumming process. The mixture was stirred for 1h.
The white-formed precipitate was separated by centrifugation for 0. The experimental set up was done as follows:. NaOH 0. After 1hour mixing the mixture was transferred into a separating funnel and allowed to stand for 1h; the soap formed was separated from the oil.
Hot water was added again and again to the oil solution until the soap remaining in solution was removed. The neutralized oil was then drawn off into beaker. The appropriate amount of alkaline solution NaOH required to neutralize the free fatty acid was calculated by the following chemical reaction. First of all, the composition of free fatty acid was determined from the acid value. The acid value is determined by using titration and the result was attached in appendix E.
The empty dish was weighed with and without the amount of kernel and dried in an oven at oC for 7hr, weighing each 2hr till constant weight is obtained and finally the weight was taken and compared with the initially recorded weight. The percentage weight in the seed was calculated using the formula:.
The sample was filled into graduated cylinder 50 ml and its temperature was recorded. Hence, the density of the oil is determined using the specific gravity. Vibro viscometer was used to determine the viscosity of oil, and the sample was kept in the water thermostat bath until it reaches the equilibrium temperature of 40 oC. After maintaining the equilibrium temperature, the Vibro viscometer tip was inserted to the sample and the reading was taken from the controller.
The kinematic viscosity is then equal to the ratio of dynamic viscosity to density of the oil. The solution was filtered and stored in brown bottle for five days. A weighed quantity of the oil sample was dissolved in 25 ml of 1 to 1 mixture of ethanol and diethyl ether.
The solution was titrated with 0. The volume of 0. The Saponification Number determination was conducted by dissolving the oil in an ethanolic KOH solution. This solution is then heated for half an hour so that the oil completely dissolves in the ethanolic KOH solution.
A weighted amount of oil W was added to 25 mL of 0. The mixture was heated, and as soon as the ethanol boils, the flask was occasionally shaken using magnetic stirrer until the oil was completely dissolved, and the solution was boiled for half an hour.
After the oil was completely dissolved, 5 drops of phenolphthalein indicator was added and the hot soap solution obtained was slowly titrated with 0.
Then a blank determination was carried out upon the same quantity of potassium hydroxide solution at the same time and under the same conditions and volume Vb was recorded. The final result was calculated using equation 3. Experimental design was analyzed and done by the Design-Expert 7. Furthermore, the physicochemical analysis of the biodiesel was carried out. The three transesterification process variables studied are reaction temperature, molar ratio of methanol to oil and weight percentage of catalyst.
The reaction period and rotation speed was set at optimum point where the maximum conversion could be achieved based on literature data. Atmospheric pressure is used for all the runs.
The levels of the variables investigated are chosen by considering the operating limits of the biodiesel production process conditions. A five-level-three-factor CCD was employed in the optimization study, requiring 20 experiments. The methanol-to-oil molar ratio, catalyst concentration and reaction temperature were the independent variables selected to optimize the conditions for FAME production of tri sodium phosphate-catalyzed transesterification. Methanol to Oil ratio x2 - 2.
The order in which the runs were made was randomized to avoid systematic errors. A ml glass reactor equipped with mechanical stirrer, thermostat, and condenser was used in all experiments. A mechanical stirrer fitted with stainless steel propeller provided the mixing requirement.
The reactor assembly was then heated to the desired temperature by using thermostat. A measured amount of methanol and heterogeneous catalyst was added to the reactor. The reaction was timed as soon as mechanical stirrer was turned on. The Transesterification was carried out at optimum reaction time and rotation speed to achieve maximum conversion for 3h. Finally, after transesterification was carried out, catalyst and glycerol part was separated from the biodiesel mixture by centrifugation for 2hr.
Then, unreacted methanol and trace moisture was removed by rotary evaporator. The end product, biodiesel was obtained as a clear amber-yellow liquid.
These procedures are used for each experiments executed at different parameters using the experimental design matrix. Hence, the amount of methanol and catalyst was calculated as follows using the process parameters. Similarly, the amount of methanol and catalyst is calculated for all experiments. The tabulated result for different processes parameter was given in appendix C. The method was given in Table 2. Hydrometer was used to measure the SG of the fuels specified. The specific gravities were taken at temperatures of 15OC.
The viscosity of the Jatropha curcas oil was measured using Vibro viscometer. Vibro Viscometer integrated with a water bath thermostat was used and the sample was kept in as shown in the Fig 3. The kinematic viscosity is then equal to ratio of dynamic viscosity to the density of the biodiesel observed. The device will detect the viscosity with vibration. During vibration, there is a shear force between the tip and the fluid. It will read the dynamic viscosity which is resistance to flow. The observed kinematic viscosity was The acid value was determined to know the amount of free fatty acid composition in the oil.
A weighted amount of biodiesel W was added to 25 mL of 0. Calorific value energy content or heat of combustion of a fuel was determined by bomb calorimeter.
Benzoic acid was used to standardize the calorimeter. One gram of sample was taken in a crucible and made into a pellet and the initial weight was noted.
It was placed in the bomb, which is pressurized to 18atm of oxygen. The bomb was placed in a vessel containing a measured quantity of water g. The ignition circuit was connected and the water temperature noted. After ignition the temperature rise was noted every minute till a constant temperature was reached. The pressure was released and the length of unburned fuse wire was measured.
The calorific value was calculated from Eq. Including the corrections for heat transfer between the surrounding and the apparatus, heat liberated by the glowing wire etc, the heat value of the air- dried sample of the fuel is expressed according to the following formula. The Iodine value of the biodiesel was determined using the empirical formula suggested by Dembirbes for determination of higher heating value.
After rearrangement the iodine value was calculated from Eq. HHV - The cetane number of the biodiesel was determined using the empirical formula suggested by Kalayasiri et al.
The flash point of the biodiesel was determined using open cup method. The cup was filled with the biodiesel up to the mark about 75 ml and the cup was heated by a Bunsen burner. Small open flame was maintained from an external supply of natural gas. Periodically, the flame was passed over the surface of the oil. When the flash temperature was reached the surface of the oil catch flame, the temperature at the moment was noted and reported as flash point temperature.
A summary of the procedure steps was the sample has to be cooled at a 2Oc rate and continuously monitored until the cloud appears and the temperature is recorded that corresponds to the first formation of a cloud in the fuel. The cloud point is a measure of the temperature at which components in the biodiesel begin to solidify out of the solution. Then, the husk is carefully removed and the kernels thus obtained were used for oil preparation.
After sifting, 8kg of jatropha seed kernel was obtained. The 8kg clean Jatropha seed kernels were grounded by using cutting mill to 2. Then; it was dried in an oven at OC for 8hours. Again, the weight of the sample after dying was measured.
Six experiments was conducted and the moisture content was determined for each of them and averaged to give the kernel seed average moisture content of 4.
The moisture content determination of the kernel conducted laboratory result was given in the table below as follows;. From 7. The mass of the oil extracted will be calculated using the following equation:. The crude jatropha oil was degummed to remove phosphatides, gums and other complex compounds in the crude oil using 64ml of phosphoric acid and 96ml of distilled water. After degumming, 0. The detailed calculation is given in appendix C.
The specific gravity of the Jatropha oil was in agreement with the result reported by Y. Franken as given in the appendix A. The kinematic viscosity of the crude Jatropha oil was higher than the result reported by Dennis Y. Leung , Xuan Wu, M. Leung Applied Energy which was The variation in viscosity is occurred from the dependence of chemical composition of the crude oil on agro climatic conditions.
The HHV of jatropha oil was found to be The transesterification was carried out at reflux of methanol, using a ml capacity glass reactor which is equipped with a stirrer, condenser and thermostat. The statistical analysis of the biodiesel was discussed below.
The three transesterification process variables studied are reaction temperature, ratio of methanol to and weight percentage of catalyst. The Design-Expert 7. The Statistical software program was used to generate surface plots, using the fitted equation obtained from the regression analysis, holding one of the independent variables constant. Experiments were carried out to validate the equation, using combinations of the independent variables, which were not part of the original experimental design, but within the experimental region.
The response of the transesterification process was used to develop a mathematical model that correlates the yield of FAME to the transesterification process variables studied. Design Expert software version 7. The central composite design conditions and responses, and the statistical analysis of the ANOVA are given in Tables 4. The multiple regression coefficients were obtained by employing a least square technique to predict a quadratic polynomial model for the FAME content Table 4.
The actual yield of biodiesel produced at different process parameters was calculated and is given in appendix c. The model was tested for adequacy by analysis of variance. The regression model was found to be highly significant with the correlation coefficients of determination of R-Squared R2 , adjusted R-Squared and predicted R-Squared having a value of 0. The yield of the transesterification processes were calculated as sum of weight of FAME produced to weight of jatropha oil used, multiplied by The formula is given as:.
The model equation that correlates the response yield of jatropha oil to FAME to the transesterification process variables in terms of actual value after excluding the insignificant terms was given below. The quality of the model developed could be evaluated from their coefficients of correlation. The value of R-squared for the developed correlation is 0.
It implies that The graph of the predicted values obtained using the developed correlation versus actual values is shown in Figure 4. A line of unit slope, i. This plot therefore visualizes the performance of the correlation in an obvious way. The results in Figure 4. This result indicates that it was successful in capturing the correlation between the three transesterification process variables to the yield of FAME.
Values of p greater than 0. Thus, from these statistical tests, it was found that the model is adequate for predicting the yield of FAME within the range of variables studied. Predicted vs. Actual Values greater than 0. This shows that the temperature,methanol to oil ratio, catalyst and the interaction between temperature and catalyst affects the yield much significantly. The "Lack of Fit F-value" of 2. Non-significant lack of fit is good because we want the model to fit.
Based on the analysis of variance, the transesterification reaction was significantly affected by various interactions between the process variables. On the other hand, significant individual process variables that affect the transesterification reaction is reaction temperature, A, ratio of methanol to oil, B, and catalyst amount, C. This result demonstrated the advantage of using design of experiments in capturing the interaction between variables that affects the transesterification reaction.
Figure 4. It can be seen that with increasing reaction temperature, increases the yield. As seen in Figure 4. The increase in the yield of FAME at higher reaction temperature is due to higher rate of reaction.
Is it well reported in the literature that the rate constants of the transesterification reaction is strongly influenced by the reaction temperature. Due to higher rate constant at higher temperature, this will lead to higher rate of reaction and eventually higher FAME yield. The transesterification reaction is basically diffusion controlled. At lower reaction temperature, the lower viscosity of Jatropha oil might cause poor diffusion between the phases that will lead to slower rate of reaction.
However, develop- of fatty acids Berchmans and Hirata, Its properties ing countries having dearth of edible oil for consumption are close to diesel fuels, and therefore biodiesel becomes cannot afford to use these oils for biodiesel production. Among these, Jatropha curcas, a multipurpose plant opment of biodiesel and the optimization of processes to with many attributes and considerable potential, is gain- meet the standards and specifications needed for the fuel ing importance for biodiesel production Divakara et al.
Biodiesel can be produced from J. Lower toxicity, biodegradability, substantial reduc- chemical or by enzymatic transesterification. Although tion in sulfur oxide SOx gases, carbon monoxide CO , chemical transesterification is faster in terms of reaction polyaromatic hydrocarbons, smoke, and particulate mat- rate, the chemical method has several drawbacks, such as ter are the advantages of biodiesel over conventional fuels.
In contrast, enzymes allow synthesis of can grow to a height of 8 or 10 m. The branches of J. Being drought tolerant, it is easy to establish iesel; there is easy recovery of high-grade glycerol, less and grows well on both arid and semi-arid conditions.
It treatment of waste, and transesterification of oils with high can prevent soil erosion and can even grow on rock crev- free fatty acids FFA Nelson et al. Thus, enzymatic ices. Jatropha grows well on marginal soils with low nutri- transesterification is a promising alternative to overcome ent content Openshaw, Since the leaves and stems many of the drawbacks associated with chemical methods are toxic to animals, it is not browsed, but after treatment it and it is more environment-friendly.
In other words, we can be used as a nutritious animal feed. In short, J. The propagation and rapid growth, medicinal value, the high main obstacle in this method is still the cost of the enzyme, oil content of its seeds, drought tolerance, bushy nature, which can be overcome to a certain extent by immobiliza- short gestation period, and multiple uses of various plant tion. For large-scale production of biodiesel from J. These are some technical ways to improve biodiesel quality.
The seed kernels of J. Biodiesel can be raw material for biodiesel production Foidl et al. Some of the frequently In general, the seeds of the physic nut are toxic to used vegetable oils for biodiesel synthesis are sunflower humans and animals. Curcin, a toxic protein isolated oil Soumanou and Bornscheuer, , canola oil from the seeds, was found to inhibit protein synthesis in Chang et al.
The high concentration of phorbol esters For personal use only. The choice of a biodiesel crop depends mainly on the toxicity Adolf et al. The oil geographical distribution; thus soybeans for the United also contains some anti-nutritional factors and thus is States, rapeseed sunflower oils for Europe, palm oil for rendered unsuitable for cooking purposes Makkar et al. The fact that this oil cannot Since there is a global crisis for food, non-edible oils are be used for nutritional purposes without detoxification preferred sources for biodiesel production in the devel- makes it attractive as a non-edible vegetable oil feedstock oping world Bordoloi and Sarmah, Shah and in the oleochemical industries biodiesel, fatty acids, Gupta have put forward the importance of using soap, surfactants, detergents, etc.
Currently, J. The fatty acid composition of Jatropha oil varies from Much attention and further research should be focused one country to another.
Saturated fatty acids of Jatropha on this plant to help solve the energy crisis problem. Some of The complete removal of the toxins from the oil is a the oil-yielding types are Jatropha pohliana, Jatropha gos- necessary step before it can be utilized on a commercial sypiifolia, Jatropha multifida, and J. Out of these, J. Conventionally, oil is extracted from seeds by a curcas has gained importance for several reasons. Linnaeus mechanical press. New techniques, such as enzyme-as- was the first to name the physic nut J.
It is a native sisted three-phase partitioning TPP Shah et al. Improper handling and Asia. Its distribution was conducted by the Portuguese and inappropriate storage leads to an increase in water ships via the Cape Verda islands and Guinea Bissau Heller, content, which can cause oil deterioration. Jatropha oil There is a need for Romijn, , aqueous oil extraction Shah et al. During carbon dioxide extraction Yan et al.
Mechanical enzymatic transesterification of Jatropha oil, lipase con- pressing is the conventional oil extraction method and is verts the FFA to biodiesel.
Therefore, the non-edible veg- applied on a small scale and in rural areas. For example, etable oil of J. The physicochemical and the performance characteristics main drawback of mechanical pressing is that only a compared with conventional diesel to facilitate continu- small amount of oil can be extracted from the seeds.
In ous operation without many changes in the design of the other words, huge quantities of seeds would be required diesel engines Sayyar et al. The J. Jatropha is of inter- ising tool for oil extraction from plants Rosenthal et al.
Aqueous oil extraction has been reported to be an acteristics. The oil is potentially valuable because of the environment-friendly oil extraction technique that has sat- properties such as low acidity, better oxidation stability isfactorily given higher oil yields. Since this and less processing cost compared with corn ethanol method is environment-friendly, the reaction does not pro- Tapanes et al.
In addition, Jatropha oil is odorless duce harmful volatile organic compounds that could lead and colorless when fresh, it turns yellow on standing, and to atmospheric pollution. However, the main drawback is it is a slow drying oil. The oil content of the seed varies the long process time required for the enzymes to liberate For personal use only. The presence of phorbol esters and curcin enzymes used by the researchers is also noted as another in the seeds and oil are toxic, but the oil is still suitable disadvantage of this extraction process Shah et al.
The fatty acid composi- In another method, referred to as the enzyme-assisted tion of Jatropha oil consists of myristic, palmitic, stearic, TPP method, a combination with sonication and enzyme arachidic, oleic, and linoleic acids Table 1. The since it has been recognized around the world as a poten- advantages of this method include easy performance and tial plant that could replace petroleum-based diesel. However, the high cost The oil extracted from this plant is renewable, clean, and of the enzyme and high-energy input for sonication can safer to use.
The carbon dioxide emissions from Jatropha pose economic obstacles. This in turn makes Jatropha biodiesel Jatropha oil has also been extracted using supercritical superior to regular diesel fuel Pan et al. In one such study by Yan et al. After harvesting the seeds, oil has to be extracted and , a yield of There are various methods tion time.
A yield of Fatty acid composition of crude Jatropha curcas oil Berchmans and Hirata, Table 2. Physicochemical properties of Jatropha curcas oil catalyst and this makes the separation process difficult Pramanik, Acid-catalyzed J.
During enzymatic transesterification Iodine No. Although this Chemical transesterification of J. This is the the high cost Yan et al. Oil extraction using differ- method commonly taken on commercial scale.
The basic ent solvents has also been examined for J. A ether, with an extraction efficiency of Both methyl esters and ethyl esters were produced from crude Jatropha oil by Foidl et al.
Potassium For personal use only. Biodiesel production from J. Chemical, physical, and through transesterification of triacylglycerols TAGs con- fuel parameters were also analyzed for Jatropha oil, and tained in plant oils are named biodiesel Antczak et al.
Biodiesel is produced from J. The quality of crude Jatropha oil transesterification of J. This leads to a high amount of soap and inappropriate storage conditions. In addition, exposure to open air and sunlight also lyzed pretreatment step. An optimized process for the reduction of content have significant effects on the transesterifica- FFA was developed by Tiwari et al. Crude Jatropha oil contains higher concen- time of 1.
The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author. Tiwari, A. Kumar, and H. Meher, D. Material and methods.
Experimental procedure. Acid pretreatment step. Sample treatment. Results and discussion. Introduction economic property. In recent years, the fossil fuel resources are depleting rapidly with consequent environment degradation. Before a capita energy consumption of a nation is the indication of its serious catastrophic stage arrives, it becomes highly imperative to search alternative fuel options based on renewable energy.
Jain, M. Literature review renewable lipid feedstocks such as vegetable oil or animal fat, is providing a substitute of or additive to diesel in developing as well Numerous studies have been carried out on the kinetics of as developed countries [2,3].
The current challenges are to reduce its mental concerns point of view as it can offer large scale production cost which is still higher than petrodiesel due to higher employment in the growing and processing of resource particu- cost of non-edible oil resources.
Dufek et al. Freedman et al. Noureddini and Zhu option for the production of biodiesel due to its low cost and simple [25] studied the effect of mixing of soyabean oil with methanol on method. The alkali and acid-catalyzed Separate acid-catalyzed, alkali-catalyzed, enzyme-catalyzed, or processes have proved to be more practical nowadays. Diasakov et al. For the oils 8C with a molar ratio of methanol to oil of Asakuma et al. There is therefore very various triglycerides using Gaussion software and found that the little chance of using edible oils for biodiesel production to ensure effect of structure of TG on the reactivity is not particularly large.
However, the non-edible oil resources can be Barnwal and Sharma [3] carried out the techno-economic analysis feedstocks for biodiesel production. Madhuca indica, Shorea robusta, Pongamia costliest biodiesel Rs. Saiffudin and Chau [38] biodiesel. Therefore chemical analysis only parameter to monitor the rate of reaction and that three step with respect to FFA and their consumption is a must.
Capillary GC by homogeneous catalysis is the most used one [50—57]. The production of fuel quality separate acid-catalyzed process which takes much longer time for biodiesel from low-cost high FFA jatropha and karanja oil was its completion as evidenced by limited reports available in the investigated.
Ahn et al. It was produce biodiesel. Yang et al. Cvengro and Povaz [60] described biodiesel fruit oil biodiesel obtained are similar to the No. Boocock et al. Delhi in the year December The fatty production of high quality biodiesel from microalgal oil. Zhu et al. Li et al. A packed-bed reactor PBR system using fungus whole-cell biocat- The experiments were conducted in a batch reactor of 1.
Fatty acids and temperature measurement instrument. The whole setup was methyl esters were prepared by Hernando et al. Nitrogen was used as carrier gas. The type of stabilities of biodiesel with respect to time. Free fatty acids in the helpful while producing biodiesel. Jain and Sharma [71] have samples were determined using stock solution Methyl heptade- evaluated the performance of diesel engine—generator system canoate and n-heptane. Base catalyzed transesterification Fuel Properties of Jatropha curcas Oil.
After 3 h, two distinct layers were formed and the mixture SA is total peak area from the methyl ester in C14 to that in C; was allowed to settle for 2 h or overnight. The heavier glycerol AEI is peak area corresponding to methyl heptadecanoate; CEI is layer was separated from the lighter ME layer by separating funnel.
Sample treatment mass of the sample mg. The ME layer was separated, washed with water, heated to 4. Results and discussion catalyst at an optimum temperature.
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