Biomedical Engineering Reference
In-Depth Information
3.0
Novozym 435
ROL
ITRI
2.5
2.0
1.5
1.0
0.5
0.0
Methanol
Ethanol
n-propanol
n-butanol
Figure 6. Effect of different alcohols on lipase activities. Reaction condition: Jatropha oil 5g; alcohol-
oil molar ratio 1:1; lipases 0.2g; reaction temperature 30
℃
; reaction time 60 min. [16;32]
Table 4. Cloud point and pour point of the bio-diesels from various oils
Oils
Cloud point
Pour point
Methyl
Ethyl
2-Propyl
Butyl
Methyl
Ethyl
2-Propyl
Butyl
Linseed
0
-2
3
-10
-9
-6
-12
-13
Canola
1
-1
7
-6
-9
-6
-12
-16
Sunflower
1
-1
n.d.
n.d.
-8
-5
n.d.
n.d.
Rapseed
0
-2
n.d.
n.d.
-15
-15
n.d.
n.d.
Soybean
5
3
n.d.
n.d.
6
n.d.
n.d.
n.d
Recycle
12
9
n.d.
n.d.
n.d.
n.d.
n.d
n.d.
Also, the usage of supercritical alcohol has been shown to be able to perform
esterification and transesterification simultaneously. This means that feedstocks with high
fatty acid content can also be used. Typically, esterification is performed as an expensive
pretreatment to the feedstock to reduce free fatty acid content [20]. Afterwards, steps for
catalyst and soap removal are also necessary, but not when using super critical methanol,
which requires no catalyst and also esterifies FFAs [20].
2.5. Catalyst
Because the reaction does not heavily favor one side or the other, a catalyst is essential
for an efficient and higher yield reaction. The common types of catalyst used are acid, base,
