**4. Results and discussion of results**

### **4.1 Results and statistical analysis of experimental results**

Tables 4.1 and 4.2 present the results on the extraction of oil from moringa oleifera seed with hexane and ethanol as the solvent respectively at different temperature, particle size and resident time. Results obtained as presented indicate that there are thirty two experimental runs with two replicates each for sixteen samples. It can be seen from the results that the extraction time, temperature, particle size and type of extraction solvent affects the rate of extraction of oil from oleifera moringa seed. Ethanol plays a major role in the production of biodiesel from oil, achieve a suistainable production of biodiesel therefore, it is important to employ a cheap and suistanable method of ethanol production. In this work the production of bioethanol from agricultural waste (rice waste) was also conducted and the results obtained are presented in Tables 4.3 and 4.4.

Results presented reveals that at the extraction conditions combination with all samples at low levels, the oil yield was 37.78% and 37.35% for the replicate using n-hexane. Ethanol yielded 19.90% and 20.25% for the replicate. While For treatment combination where the temperature was high (65oC) while particle size and extraction time were low (500μm and 6hr respectively) n-hexane yielded 38.58% and 38.37% for the replicate. Ethanol at a high temperature of 75oC and particle size (500μm and extraction time of 6hrs yielded 20.82% and 21.23% for the replicate. Similarly For treatment combination where the temperature was low (55oC) while particle size high (710μm) and extraction time low (6hr) n-hexane yielded 43.17% and 43.26% for the replicate. Ethanol at a low temperature of 65oC, particle size high (710μm) and extraction time low (6hrs) yielded 38.71% and 38.65% for the replicate. While for extraction combination where the temperature was (55oC) and particle size (500μm) are low, extraction time was high (7hrs) n-hexane yielded 42.22% and 41.98% for the replicate. Ethanol at a low temperature and particle size (65oC and 500μm respectively) and extraction time high (7hrs) yielded 22.16% and 21.96% for the replicate. Also for the extraction conditions combination where the temperature and particle size were high (65oC and 710μm respectively) and extraction time were low (6hr) n-hexane yielded 43.01% and 42.95% for the replicate. Ethanol at a high temperature and particle size of (75oC and 710μm respectively) and low extraction time of 6hrs yielded 35.32% and 35.68% for the replicate. Results

or hose were connected to the condenser to supply water from the tap for cooling the condenser to supply water from the tap for cooling the condenser and letting out water out of the condenser simultaneously. Temperature on the heating mantle was set to the standard temperature for the production of ethanol which is 78.3oC, as the filtrate was heated, the vapour rose and entered into the condenser, tap water was passed into and out of the condenser using the rubber pipes and this condenses the vapor from the heated filtrate, condensed vapour was collected into the beaker at the other end of the distillation set up as the distillate (bio-ethanol), this process was repeated for other samples. The distillate was further purified by the use of calcium oxide (lime), a basic oxide, when added to the ethanol, absorbed the water to form calcium hydroxide, an alkaline solution; calcium hydroxide formed was separated from ethanol by further distillation which leaves absolute ethanol. One cm3 of alcohol was treated with iodine and sodium hydroxide, the colour change was observed and recorded, yellow precipitate was formed, which confirm that ethanol is present. The produced bio-ethanol was characterized to determine the density, flash point,

Tables 4.1 and 4.2 present the results on the extraction of oil from moringa oleifera seed with hexane and ethanol as the solvent respectively at different temperature, particle size and resident time. Results obtained as presented indicate that there are thirty two experimental runs with two replicates each for sixteen samples. It can be seen from the results that the extraction time, temperature, particle size and type of extraction solvent affects the rate of extraction of oil from oleifera moringa seed. Ethanol plays a major role in the production of biodiesel from oil, achieve a suistainable production of biodiesel therefore, it is important to employ a cheap and suistanable method of ethanol production. In this work the production of bioethanol from agricultural waste (rice waste) was also conducted and the results

Results presented reveals that at the extraction conditions combination with all samples at low levels, the oil yield was 37.78% and 37.35% for the replicate using n-hexane. Ethanol yielded 19.90% and 20.25% for the replicate. While For treatment combination where the temperature was high (65oC) while particle size and extraction time were low (500μm and 6hr respectively) n-hexane yielded 38.58% and 38.37% for the replicate. Ethanol at a high temperature of 75oC and particle size (500μm and extraction time of 6hrs yielded 20.82% and 21.23% for the replicate. Similarly For treatment combination where the temperature was low (55oC) while particle size high (710μm) and extraction time low (6hr) n-hexane yielded 43.17% and 43.26% for the replicate. Ethanol at a low temperature of 65oC, particle size high (710μm) and extraction time low (6hrs) yielded 38.71% and 38.65% for the replicate. While for extraction combination where the temperature was (55oC) and particle size (500μm) are low, extraction time was high (7hrs) n-hexane yielded 42.22% and 41.98% for the replicate. Ethanol at a low temperature and particle size (65oC and 500μm respectively) and extraction time high (7hrs) yielded 22.16% and 21.96% for the replicate. Also for the extraction conditions combination where the temperature and particle size were high (65oC and 710μm respectively) and extraction time were low (6hr) n-hexane yielded 43.01% and 42.95% for the replicate. Ethanol at a high temperature and particle size of (75oC and 710μm respectively) and low extraction time of 6hrs yielded 35.32% and 35.68% for the replicate. Results

pour point.

**4. Results and discussion of results** 

obtained are presented in Tables 4.3 and 4.4.

**4.1 Results and statistical analysis of experimental results** 

presented also shows that, for the extraction combination where the temperature was high (65oC), low particle size (500μm) and high extraction time (7hrs) n-hexane yielded 42.81% and 42.25% for the replicate. Ethanol at a high temperature of 75oC, low particle size (500μm) and high extraction time of 7hrs yielded 26.67% and 26.14% for the replicate. It could be observed from the Tables of result that, for treatment combination where the temperature was low (55oC) while particle size and extraction time were high (710μm and 7hrs respectively) n-hexane yielded 41.38% and 41.35% for the replicate. Ethanol at a low temperature of 65oC, high particle size and extraction time (710μm and 7hrs respectively) yielded 28.84% and 28.24% for the replicate. Finally, for extraction condition combination where all the parameters are high temperature (65oC), particle size and extraction time were (710μm and 7hr respectively) n-hexane yielded 42.03% and 42.52% for the replicate. Ethanol at a high temperature of 75oC, particle size and extraction time (710μm and 7hrs respectively) yielded 24.75% and 25.03% for the replicate


Table 4.1. Oil yield at various conditions from the first run with hexane and ethanol as the solvent

Extraction and Optimization of Oil from

as the extraction solvent respectively.

Table 4.4. Factors and their coded levels

Run A B C

Run A B C

4.7 for n-hexane and ethanol.

Factor Code

Treatment

Treatment

Level of

**4.1.1 Statistical analysis of experimental results** 

Moringa Oleifera Seed as an Alternative Feedstock for the Production of Biodiesel 257

Statistical analyses were conducted with the aim of developing a model to represent the relationship between the factors investigated and the yield of oil from the moringa oleifera seeds with hexane and ethanol as the extraction solvent. Table 4.4 shows an estimation of upper and lower levels of the three factors (temperature, particle size and time). While Tables 4.5 and 4.6 indicates factorial experimental design results with n-hexane and ethanol

The average effect of a factor which is described as the change in response produced by a change in the level of factor response produced by a change in the level of factor averaged over the levels of other factors. This has been calculated and subsequently tabulated in Table

> A Temperature (oC)

Hexane Ethanol High level +1 65 75 710 7 Low level -1 55 65 500 6

1 I -1 -1 -1 37.78 36.92 37.35 2 A +1 -1 -1 38.58 38.15 38.37 3 B -1 +1 -1 43.17 43.26 43.22 4 C -1 -1 +1 42.22 41.98 42.10 5 Ab +1 +1 -1 43.01 42.95 42.98 6 Ac +1 -1 +1 42.81 42.25 42.53 7 Bc -1 +1 +1 41.38 41.35 41.37 8 Abc +1 +1 +1 42.03 42.52 42.28 Table 4.5. 23 Factorial experimental design results using n-hexane as extraction solvent

1 I -1 -1 -1 19.90 20.25 20.08 2 A +1 -1 -1 20.82 21.25 21.04 3 B -1 +1 -1 38.71 38.65 38.65 4 C -1 -1 +1 22.16 21.96 22.06 5 Ab +1 +1 -1 35.32 35.68 35.50 6 Ac +1 -1 +1 26.67 26.14 26.41 7 Bc -1 +1 +1 28.84 28.24 28.54 8 Abc +1 +1 +1 24.75 25.03 24.89

Table 4.6. 23 Factorial experimental design results using ethanol as extraction solvent

combination Design factor First yield Y1 Second yield Y2

combination Design factor First yield Y1 Second yield Y2

B Particle Size (µm)

C Time (hrs)

Average yield Yav

Average yield Yav


Table 4.2. Oil yield at various conditions from the second run with hexane and ethanol as the solvent


Table 4.3. Ethanol production using Zymomonas mobilis from distillation process


Table 4.4. Properties of produced ethanol compared to commercial ethanol
