Page 245 - Biofuels Refining and Performance

228 Chapter Eight

O
O C H
H C C 17 35
2
HC O C C H 35
17
O
H C C
2
O C H 35
17
O
Diffusion

H 2 CH
C C 3
C
O HC O C C H CH 3
H 35 17 O Reaction
H C O 17 35
35 17
C C O
O H 2 CH 3
Figure 8.5 Scheme of restructuring triglycerides with shape-
selective H-ZSM-5 to aromatic hydrocarbons.

To demonstrate this influence of catalysts and reaction temperature
on yields and products, Table 8.4 considers a shape-selective zeolite
type H-ZSM-5, commercially available as Pentasil, PZ-2/50H, and Y-
zeolite (DAY-Wessalith). The physical characteristics of oils formed from
the conversion of animal fat (rendering plant) are depicted [56]. Yields
are between 30% and 70%, depending on the type of zeolite and tem-
perature. Net calorific values are in the range of 40 MJ/kg compared to

TABLE 8.4 Yields and Physical Characteristics of Hydrocarbons from
Catalytic Conversion of Animal Fat Using Zeolite Types H-ZSM-5
(Pentasil, PZ-2/50H) and DAY-Wessalith at Different Temperatures
H-ZSM-5 H-ZSM-5
PZ-2/50H, PZ-2/50H, DAY-Wessalith,
Parameter T 550 C T 400 C T 400 C
Yield, % 31.48 56.74 72.9
NCV, MJ/kg 40.1 40 41.3
Density, g/mL 0.83 0.85 0.81
2
Viscosity, mm /s 0.92 1.01 2.29
C, % 88.6 84.5 83.4
H, % 10.7 12.5 13.5
N, % <0.14 <0.14 <0.14
S, % <0.34 <0.34 <0.34