Effect of initial catalyst amount on production of bio-diesel from Jatropha Curcas seed using in-situ technique

The effectof initial catalyst amount(0.3 -1.5%) on the in-situproduction of biodiesel from raw Jatropha Curcas seed was studied at a reaction temperature of 600C and reaction time of between 120min. Central composite experimental design was applied to evaluate effect catalyst amount (0.3 –1.5%). Initial catalyst amount was found to have significant (P<0.05) positive influence effects on the yield up to a value of between 0.9 and 1.20 g/g after which there was a significant reduction in the yield of biodiesel produced. Due to formation of by-products (soaps) caused by excessive amount of catalyst there was a general reduction in Jatropha Curcas ethyl-ester as levels of catalyst amount increased. A cubic quadratic model was obtained to predict the yield as a function of catalyst amount. The model predicted well the observed data with a R2 value of 0.939 and a non-significant Lack-of-Fit (P<0.05). The optimal value for initial catalyst amount was obtained as 1.01g/g. The biodiesel obtained at optimal catalyst amount compared favorably with the ASTM D6751-02 standard for biodiesel

CONVECTIVE THIN-LAYER DRYING AND REWETTING CHARACTERISTICS OF SESAME SEED

Fundamental information on drying and re-wetting characteristics of agricultural seeds is required in the design and aeration systems as well as in the prediction of drying rate using various mathematical models. Thin-layer drying experiments were conducted using air-ventilated oven to simulate the artificial drying and rewetting processes of sesame seed (6.9 to 18.2% w.b) at three drying temperatures of 40, 50 and 60oC. Five drying models were applied to the thin-layer data. The Page equation fitted the data best after comparing the determination of coefficient (R2), the standard error of moisture content (SEM) and mean relative percent error (e) between the experimental and predicted values. The drying rate of sesame seed under drying and rewetting conditions increased with increased temperature of drying( 40 to 60oC) and initial moisture content of seed( 6.9, 11.5 and 18.2% w.b).  The parameters K and n of the page model was related to the drying temperature and moisture content by two empirical expressions of Page equation for predicting moisture ratio. The coefficient of determination (R2) for parameters K and n were 0.95 and 0.87 respectively.  The effective diffusivity was found to be 2.32 x 10-11 m2s-1

INFLUENCE OF CATALYST QUANTITY AND REACTION TIME ON IN-SITU PRODUCTION OF BIODIESEL FROM RAW CASTOR BEAN SEED USING RESPONSE SURFACE METHODOLOGY

Trans-esterification is the most commonly used methods of biodiesel production. In-situ trans-esterification process uses oil (triglycerides) in seeds directly without the need for initial extraction. The in-situ production of biodiesel from raw castor bean seed with a batch processor was studied at initial catalyst quantity of 0.1, 0.5 and 1.5%, reaction time of 30, 60 and 90 min with a reaction temperature of 600C and alcohol seed ratio of 1:1 using the response surface methodology.  Initial catalyst concentration and reaction time were subjected to central composite experimental design of the response surface methodology.  Initial catalyst quantity and reaction time were found to have significant (P&lt;0.05) effects on the yield of castor biodiesel produced, with increased catalyst quantity giving a negative effect on the yield after an initial amount of between 1.0 and 1.2%.  The reaction time had a positive effect on the yield until after 90 minutes after which biodiesel yield reduced with increased time. The CA-Time interactions influence was small and negative, due to the superior effect of initial catalyst quantity by the formation of by-products (soaps) leading to difficult ester separation from glycerol. A second-order model was obtained to predict the yield as a function of all factors. The model predicted well the observed data with a R2 value of 0.983. The biodiesel produced had properties comparable to the standards of ASTM while the specific gravity was higher than the specified standards

PRODUCTION OF BIO-DIESEL FROM JATROPHA CURCAS SEED USING IN-SITU TECHNIQUE: EFFECT OF CATALYST AMOUNT AND ALCOHOL-SEED RATIO

The effect of alcohol seed ratio(0.5,1.5 &amp; 2.0) and initial catalyst amount(0.5,1.0 &amp; 1.5%) on the in-situ production of biodiesel from raw Jatropha Curcas seed was studied at a reaction temperature of 600C and reaction time of 120min.&nbsp; Central composite experimental design was applied to evaluate effects of alcohol-seed weight ratio (0.5 – 2.0) and initial catalyst amount (0.5 – 1.5%).&nbsp; Initial catalyst amount and alcohol seed ratio was found to have significant (P&lt;0.05) effects on the yield.&nbsp; Initial catalyst amount was the more important factor and had a positive influence on the yield than alcohol seed ratio which does not significantly affect the yield as a single factor. Due to formation of by-products (soaps) caused by excessive amount of catalyst and excess alcohol leading to difficult ester separation from glycerol, there was a general reduction in Jatropha Curcas&nbsp; ethyl-ester as levels of catalyst and alcohol seed ratio increased.&nbsp; A second-order model was obtained to predict the yield as a function of all factors. The model predicted well the observed data with a R2 value of 0.985 and a non-significant Lack-of-Fit (P&lt;0.05). The biodiesel obtained, compared favorably with the ASTM D6751-02 standard for biodiesel but the viscosity

PRODUCTION OF BIO-DIESEL FROM JATROPHA CURCAS SEED USING IN-SITU TECHNIQUE: EFFECT OF CATALYST AMOUNT AND ALCOHOL-SEED RATIO

The effect of alcohol seed ratio(0.5,1.5 &amp; 2.0) and initial catalyst amount(0.5,1.0 &amp; 1.5%) on the in-situ production of biodiesel from raw Jatropha Curcas seed was studied at a reaction temperature of 600C and reaction time of 120min.&nbsp; Central composite experimental design was applied to evaluate effects of alcohol-seed weight ratio (0.5 – 2.0) and initial catalyst amount (0.5 – 1.5%).&nbsp; Initial catalyst amount and alcohol seed ratio was found to have significant (P&lt;0.05) effects on the yield.&nbsp; Initial catalyst amount was the more important factor and had a positive influence on the yield than alcohol seed ratio which does not significantly affect the yield as a single factor. Due to formation of by-products (soaps) caused by excessive amount of catalyst and excess alcohol leading to difficult ester separation from glycerol, there was a general reduction in Jatropha Curcas&nbsp; ethyl-ester as levels of catalyst and alcohol seed ratio increased.&nbsp; A second-order model was obtained to predict the yield as a function of all factors. The model predicted well the observed data with a R2 value of 0.985 and a non-significant Lack-of-Fit (P&lt;0.05). The biodiesel obtained, compared favorably with the ASTM D6751-02 standard for biodiesel but the viscosity

EFFECT OF TEMPERATURE AND PERCENTAGE OF INITIAL CATALYST ON THE IN-SITU PRODUCTION OF BIO-DIESEL FROM CASTOR OIL BEAN SEED USING RESPONSE SURFACE METHODOLOGY

The use of vegetable oil and animal fats for biodiesel production has recently become a great concern because of the competition with food materials.  As the demand for vegetable oil increase tremendously in recent years it has become impossible to justify the use of these oils for fuel production. In-situ trans-esterification process uses the oil (triglycerides) in the oil seed directly without the need for initial extraction as compared with the conventional trans-esterification. Castor oil bean seed contains between 35 and 55% oil and does not compete with food grade oil because of the seed’s toxicity. This study evaluated the effect of temperature and percentage of initial catalyst on yield of castor ethyl ester.  Raw castor oil bean seed kernel at moisture content of 4.68 % (db) was subjected to in-situ trans-esterification in a batch processor with ethanol as the solvent and sodium hydroxide as the catalyst.  Central composite design (CCD) of the Response surface methodology was applied to evaluate the main and interactive effects of initial catalyst amount (0.5 – 1.5%) and reaction temperature (40 – 70OC), on yield of castor ethyl-ester, at reaction time of 120 minutes and alcohol-seed weight ratio of 1:1.  A quadratic non-linear polynomial model was obtained to describe the effect of the factors on yield.  The model was significant (P&lt; 0.05) with a non- significant Lack-of-Fit value (P&lt; 0.05) and R2 value of 0.944. Second order response surfaces and contour plots obtained from the model revealed that initial catalyst amount was the more effective factors on yield while reaction temperature had less effect. The Temperature–percentage of initial catalyst interaction was small and negative, due to the combined effects of formation of by-products (soaps) and saponification. The biodiesel produced from ground castor oil bean seed during this study met the requirements of ASTM standard D6751-02 but specific gravity was higher than the ASTM standard confirming that biodiesel produced from castor bean seed using the in-situ technique can be used as replacement fuel for fossil diesel

Optimization of in-situ Biodiesel Production from Raw Castor Oil-Bean Seed

Optimization of in-situ biodiesel production from raw castor oil-bean seed was carried out from raw castor bean oil seed (37.9% oil content) by alkaline catalyzed in-situ trans-esterification with Sodium hydroxide as catalyst and ethanol as the solvent in a laboratory batch processor.  Response surface methodology and central composite experimental design was applied to evaluate effects of reaction time (30 -120 min), alcohol/seed weight ratio (0.5 – 2.0), Catalyst amount (0.3 – 1.5%) and reaction temperature (40 – 70OC).  Catalyst amount, reaction temperature and time all had significant main effects (p &lt; 0.05) while Alcohol-seed ratio had only slight effects on yield of castor biodiesel as a main effect but was significantly involved in interactions with other factors.  A modified statistical model comprised of all significant factors and interactions (p &lt; 0.05) obtained by multiple regressions predicted that the highest yield of castor ethyl-ester was 99.5% of expressible oil at the following optimized reaction values; alcohol/seed weight ratio of 0.5, a catalyst./seed weight ratio of 1.31, reaction temperature of 60.33oC, and reaction time of 81.7minutes.  A Taguchi L9(3^4)  optimization experimental design used to confirm the modified model at optimum point and two other points within experimental region produced yield that was significantly comparable to model predictions at 95% confidence level using  a paired t-test. Measured properties of the castor ethyl-ester such as viscosity(5.78mm2/s), pour point (-21.5 oC), flash point (177.12 oC), calorific value (47.76MJ/kg), acid value (0.34 mg KOH/g) and cetane number (48.73) were within the ASTM standard D6751-02 but specific gravity. Keywords: Castor oil-bean seed, biodiesel, in-situ trans-esterification, response surface methodology, optimization, Castor ethyl-este

DRYING CHARACTERISTICS OF KEREWA TOMATO UNDER INFRARED DRYING

&nbsp;In Drying characteristic for infrared drying of tomato slices were investigated. The drying experiments were carried out using Kerewa local varieties of tomato at five infrared drying power (150, 250, 300, 400 and 500 W) with slice thickness of 10 mm. For all drying powers there was a reduction in moisture content with increased drying time, the drying took place in the falling rate period. The drying time reduced as the infrared heating power increased from 150 to 500W. The diffusivity obtained for the tomato slices were within the range specified for fruits and vegetables with a value of 5.6132 x 10-7 m/s2.&nbsp; Blanched tomato varieties had better rehydration capacities than all unblanched samples

MOISTURE DEPENDENCE OF SOME AERODYNAMIC PROPERTIES OF BENISEED

Some aerodynamic properties of two varieties of beniseed (Yandev 55 and E8) were determined at&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;moisture content levels of 5.3, 10.6, 16.1 22.4, 28.3 per cent (wet basis). The determined properties&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;were particle diameter, frontal area, terminal velocity and drag coefficients. A - 2 x 5 factorial experi-&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;ment in Completely Randomized Design with a total of 30 observations was used for each of the pa-&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;rameters. The particle diameter and frontal area increased from 1.52 to 1.78mm and 1.77 to 2.49 mm2&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;for Yandev 55; 1.74 to 2.18 mm and 2.38 to 3.73 mm2 &nbsp; &nbsp;for E8 respectively as the moisture content&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;increased from 5.3 to 28.3%. &nbsp;The respective terminal velocities decreased from 3.05 to 2.74m/s and&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;2.80 to 2.48m/s for Yandev 55 and E8 within the studied moisture content levels. Increasing the mois-&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;ture content from 5.3 to 16.10% increased the drag coefficient from 2.67 to 2.70 and 2.74 to 2.78 for&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;the two accessions respectively. A further increase to 22.4% decreased the respective values to 2.64&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;and 2.61. The effect of moisture content on beniseed was highly significant on the terminal velocity.&nbsp

REVIEW ON CASSAVA MASH SIF TING METHODS AND MECHANISMS

Cassava is presently the most important food crop in Nigeria from the point of view of both the area cultivated and the tonnage produced.Cassava has transformed greatly into high yielding cash crop, a foreign exchange earner as well as a crop for world food security and industrialization. As a result of this, there has been an unprecedented rise in the demand for cassava and its numerous products worldwide for both domestic and industrial applications. However, cassava processors are currently finding it extremely difficult to respond positively to this increase in demand due to the prevalence of the traditional processing methods employed the sifting operation inclusive. This has made the appraisal of the current sifting technologies pertinent in order to address the areas that need technical improvement and further research efforts towards the evolution of cost effective sifting technologies with improved efficiencies which would enhance the capacity to exploit the cassava market potential.&nbsp; Therefore, this paper reviews the efforts made, and currently being made towards an efficient and cost effective mechanization of cassava mash sifting operation so as to overcome the challenges being faced using traditional method of sieving cassava mash