Biomedical Engineering Reference
In-Depth Information
TABLE 2.7 Selected Chemical and Physical and Properties of Potential
Luminosity Additives
Parameter
Toluene
Hexane
Chemical name
Phenyl methane
n-Hexane, dipropyl
Molecular formula
C
7
H
8
C
6
H
14
Molecular weight (g/mol)
92.14
86.18
Specific gravity
0.867
0.6548
Boiling point (
C)
110.6
95
Log K
ow
(
)
2.73
4.11
Henry's constant (
)
0.272
0.130
Solubility (in water) (mg/l at 20
C)
526
9.47
Vapor pressure (atm)
26.31
4.89
Appearance
Colorless, liquid with aromatic odor
2.4.1 Luminosity
Several types of compounds have been identified to increase the
luminosity of methanol, including hydrocarbon mixtures, aromatics,
aliphatics, olefins, other alcohols, ethers, metal organic salts, and
alcohol soluble organic dyes. For example, varying toluene content
from 4% to 10% increases methanol fuel's luminosity 10-100 times.
Selected chemical and physical properties of two potential luminosity
additives are presented in Table 2.7.
In general, the fate and transport of toluene and hexane are well
understood based on their physiochemical properties. They have rela-
tively high vapor pressures, are readily biodegraded under aerobic
conditions, and exhibit more retardation than methanol because of
their lower solubilities and higher soil partition coefficients.
2.4.2 Taste
Studies conducted by Lawless et al. (1983) demonstrated that addition
of a bitterant reduces accidental ingestion of a product. The potential
health concerns associated with ingestion of methanol-containing fuels
have prompted the consideration of bitterants to prevent such ingestion.
