Biomedical Engineering Reference
In-Depth Information
20000
Diesel
18000
Yellow
grease
Edible
Tallow
Inedible
Tallow
Canola
Soybean
Recycle oil
Lard
16000
14000
12000
10000
8000
6000
4000
2000
0
Figure 15. Heating value of diesel and varied biodiesel (B100) fuels.
Table 13. Summary of alternative transesterification procedures
Transesterification
Methods
Maximal
yield (%)
Catalyst
(%)
Temp.
(
℃
)
Time
(minute)
Alcohol:oil
ratio
Solid super base catalyst
93
1.5
70
150
9:1
In situ (without oil extraction step)
87
1.0
60
60
-
Supercritical alcohols
99
0
200-250
40
50:1
Enzymatically in the presence of
supercritical CO
2
70
0
45
480
5:1
4. Manufacturing Art
There are many methods of producing biodiesel. In this section, a few of these methods
are described in detail. Other methods are often combinations or slight deviations from the
methods described. As an example, Table 13 includes a summary of a variety of methods to
produce biodiesel. Most biodiesel production facilities utilize the conventional methods of a
batch or continuous reactor process. These processes utilize the classic ingredients discussed
above. Typically, the proportions used are:
•
Reactants: Fat or Oil (e.g. 100 kg soybean oil)
•
Primary Alcohol (e.g. 10 kg methanol)
•
Catalyst: Mineral Base (e.g. 0.3 kg sodium hydroxide)
•
Neutralizer: Mineral Acid (e.g. 0.25 kg sulfuric acid)
