Biodiesel, manufacture

Fatty acid methyl esters (FAME) are currently manufactured mainly by trans-esterification with an alcohol, using a homogeneous base catalyst (NaOH/KOH). Methanol is more suitable for biodiesel manufacturing, but other alcohols can in principle also be used, depending on the feedstock available. The... 

Figure 14.1 Evolution of biodiesel manufacturing capacity in Europe.

Figure 14.2 Batch-process flow diagram for biodiesel manufacturing.

The second area of heterogeneous catalysis in biodiesel manufacturing is the transesterification reaction. Here again, the base catalysts exhibit typically much higher activity than the acidic ones, but finding effective catalysts is still an open problem. Some solid metal oxides, such as those of tin, magnesium, and zinc could be used directly, but they actually act by a homogeneous mechanism... 

Continuous stirred-tank reactors (CSTR) are currently used for biodiesel manufacturing. Obviously, a single CSTR would require a huge volume to achieve the performance of a batch or PFR-like reactor, but the use of several CSTRs in series can improve the productivity considerably (Figure 14.12a). Intermediate... 

A key operation in biodiesel manufacturing is the separation of glycerol and FAM E from the reaction mixture by liquid-liquid decanting. Thermodynamic studies on this subject are scarce despite the industrial interest Table 14.11 presents data for... 

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