methanogenic archae (cf. Sect. 14.2.6). Branched alkanes
(iso and anteiso) with short carbon chain length and with
odd carbon chain length predominance (C 15 and C 17 )
are considered as bacterial biomarkers*. Pristane and
phytane are widely distributed; they were detected in
photosynthetic microorganisms, heterotrophic bacteria,
some zooplankton species, and macrophytes. The unsaturated compounds, alkenes, are synthesized by a number
of marine organisms and higher plants. These compounds
are highly unstable and quickly transformed by diagenetic processes, which explains their absence in fossil
resources. As to aromatic hydrocarbons found in small
COMPOSES SOUFRES
ORGANOSULFUR
COMPOUNDS
5%
5%
METAUX
COMPOSES AZOTES
COMPOSES OXYGENES
CRUDE OIL
CRUDE OIL
2
3
2
6
1 0
14
ASPHALTENES
PORPHYRINS
TRACE METALS
NITROGEN COMPOUNDS
OXYGEN COMPOUNDS
N
N
N
ROH
R
C
O
R'
R
C
O
OH
OH
O
O
RSH
R S R'
R
S
S R'
S
S
S
Mono-aromatic hydrocarbons
CH 3
C 2 H 5
CH 3
CH 3
CH 3
H 3 C
CH 3
+ C1 , C2, C3,... derivatives
di-aromatic hydrocarbons
Tri-aromatic hydrocarbons
+ C1 , C2, C3,... derivatives
95%
95%
R
R'
R
R'
COMPOSES AZOTES
AROMATICS
COMPOSES AZOTES
BRANCHED ALKANES
COMPOSES AZOTES
n-ALKANES
COMPOSES AZOTES
CYCLOALKANES
25 %
30 %
40 %
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19)
(20)
(21)
(22)
(23)
(24)
(25)
(26)
(27)
(30)
(28)
(29)
(31)
(32)
(33)
(34)
(35)
(36)
(37)
(38)
(39)
(40)
(41)
(42)
(43)
N
H
Fig. 16.33 Chemical composition of a crude oil. Displayed values
correspond to the composition (w/w%) of the crude oil “arabian light”
(Persian gulf). n-Alkanes: 1: n-octadecane; 2: n-heptadecane; 3: nhexadecane. Branched alkanes: 4: isooctadecane; 5: anteisooctadecane;
6: 2,6,10,14-tetramethylpentadecane (pristane); 7: 2,6,10,14tetramethylhexadecane (phytane). Cycloalkanes (naphtenes): 8:
cyclopentane and alkylated derivatives; 9: cyclohexane and alkylated
derivatives; 10: drimanes (bicyclics); 11: steranes; 12: tricyclic
terpanes; 13: tetracyclic terpanes; 14: pentacyclic terpanes (hopanes).
Aromatics: 15: benzene; 16: toluene; 17: xylenes; 18: ethylbenzene; 19:
1,3,5-trimethylbenze `ne; 20: naphthalene; 21: fluorene; 22: biphenyl;
23: acenaphthylene; 24: acenaphtene; 25: anthracene; 26: phenanthrene; 27: fluoranthene. Nitrogen compounds: 28: carbazole; 29: pyrrole; 30: quinoline; 31: pyridine. Oxygen compounds: 32: Alcohols; 33:
ketones; 34: acids; 35: phenols; 36: furanes; 37: benzofuranes.
Organosulfur compounds: 38: thiols; 39: sulfides; 40: disulfides; 41:
dibenzothiophene; 42: benzothiophene; 43: thiophene. C 1 -, C 2 -, and C 3
derivatives correspond to alkylated congeners with 1 (methyl),
2 (dimethyl or ethyl), or 3 (trimethyl, methyl, and ethyl, propyl or
isopropyl) substituents, respectively
Natural sources
Natural sources
Anthropic sources
Anthropic sources
Petrogenic
Biogenic
Diagenetic
Pyrolytic
Natural oil seeps
Pyrolytic
Fig. 16.34 Hydrocarbon sources in the environment
16 Applied Microbial Ecology and Bioremediation
717
(iso and anteiso) with short carbon chain length and with
odd carbon chain length predominance (C 15 and C 17 )
are considered as bacterial biomarkers*. Pristane and
phytane are widely distributed; they were detected in
photosynthetic microorganisms, heterotrophic bacteria,
some zooplankton species, and macrophytes. The unsaturated compounds, alkenes, are synthesized by a number
of marine organisms and higher plants. These compounds
are highly unstable and quickly transformed by diagenetic processes, which explains their absence in fossil
resources. As to aromatic hydrocarbons found in small
COMPOSES SOUFRES
ORGANOSULFUR
COMPOUNDS
5%
5%
METAUX
COMPOSES AZOTES
COMPOSES OXYGENES
CRUDE OIL
CRUDE OIL
2
3
2
6
1 0
14
ASPHALTENES
PORPHYRINS
TRACE METALS
NITROGEN COMPOUNDS
OXYGEN COMPOUNDS
N
N
N
ROH
R
C
O
R'
R
C
O
OH
OH
O
O
RSH
R S R'
R
S
S R'
S
S
S
Mono-aromatic hydrocarbons
CH 3
C 2 H 5
CH 3
CH 3
CH 3
H 3 C
CH 3
+ C1 , C2, C3,... derivatives
di-aromatic hydrocarbons
Tri-aromatic hydrocarbons
+ C1 , C2, C3,... derivatives
95%
95%
R
R'
R
R'
COMPOSES AZOTES
AROMATICS
COMPOSES AZOTES
BRANCHED ALKANES
COMPOSES AZOTES
n-ALKANES
COMPOSES AZOTES
CYCLOALKANES
25 %
30 %
40 %
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19)
(20)
(21)
(22)
(23)
(24)
(25)
(26)
(27)
(30)
(28)
(29)
(31)
(32)
(33)
(34)
(35)
(36)
(37)
(38)
(39)
(40)
(41)
(42)
(43)
N
H
Fig. 16.33 Chemical composition of a crude oil. Displayed values
correspond to the composition (w/w%) of the crude oil “arabian light”
(Persian gulf). n-Alkanes: 1: n-octadecane; 2: n-heptadecane; 3: nhexadecane. Branched alkanes: 4: isooctadecane; 5: anteisooctadecane;
6: 2,6,10,14-tetramethylpentadecane (pristane); 7: 2,6,10,14tetramethylhexadecane (phytane). Cycloalkanes (naphtenes): 8:
cyclopentane and alkylated derivatives; 9: cyclohexane and alkylated
derivatives; 10: drimanes (bicyclics); 11: steranes; 12: tricyclic
terpanes; 13: tetracyclic terpanes; 14: pentacyclic terpanes (hopanes).
Aromatics: 15: benzene; 16: toluene; 17: xylenes; 18: ethylbenzene; 19:
1,3,5-trimethylbenze `ne; 20: naphthalene; 21: fluorene; 22: biphenyl;
23: acenaphthylene; 24: acenaphtene; 25: anthracene; 26: phenanthrene; 27: fluoranthene. Nitrogen compounds: 28: carbazole; 29: pyrrole; 30: quinoline; 31: pyridine. Oxygen compounds: 32: Alcohols; 33:
ketones; 34: acids; 35: phenols; 36: furanes; 37: benzofuranes.
Organosulfur compounds: 38: thiols; 39: sulfides; 40: disulfides; 41:
dibenzothiophene; 42: benzothiophene; 43: thiophene. C 1 -, C 2 -, and C 3
derivatives correspond to alkylated congeners with 1 (methyl),
2 (dimethyl or ethyl), or 3 (trimethyl, methyl, and ethyl, propyl or
isopropyl) substituents, respectively
Natural sources
Natural sources
Anthropic sources
Anthropic sources
Petrogenic
Biogenic
Diagenetic
Pyrolytic
Natural oil seeps
Pyrolytic
Fig. 16.34 Hydrocarbon sources in the environment
16 Applied Microbial Ecology and Bioremediation
717