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Selected Case Histories of the More Detailed Chemistry Studies of Mousse Behavior and Long Term Fate in Near-Coastal and Open Ocean Oil Spills/Blowouts
Published in James R. Payne, Charles R. Phillips, Petroleum Spills in the Marine Environment, 1985
James R. Payne, Charles R. Phillips
In reference mousse samples collected with a bucket from the immediate vicinity of the broken tanker, nC-11 was the most abundant n-alkane, although an homologous n-alkane series from nC-8 to nC-30 was noted. The pristane to phytane ratio was near unity, and both nC-17 and nC-18 were more than twice as abundant as the nearest isoprenoids. Numerous alkyl-substituted aromatics, ranging from tetramethylbenzene to methylphenanthrene, were identified, as were a series of alkyl-dibenzothiophenes. The most abundant aromatic compounds in the parent mousse were naphthalenes, methylnaphtha-lenes, dimethyl naphthalenes, C3-naphthalenes, fluorene, and phenanthrene. In a sample believed to be approximately eight hours old, the normal alkane composition had been altered by evaporative weathering, and molecules boiling below nC-15 showed detectable losses relative to n-tetracosane. The nC-17/pristane and nC-18/phytane ratios were not detectably altered, however, suggesting that microbial processes had not been active up to this time (Calder and Boehm, 1981). The aromatic components in this sample were also altered by evaporation and dissolution, with removal of the alkyl-benzenes and methylnaphthalenes relative to dimethyl naphthalenes. Concentrations of phenanthrene and dibenzothiophene were not appreciably reduced in this sample relative to those in the reference mousse.
Asphalt Chemistry: An NMR Investigation of the Benzylic Hydrogens and Oxidation
Published in Arthur M. Usmani, Asphalt Science and Technology, 1997
R. W. Jennings, Jacqueline Fonnesbeck, Jennifer Smith, J.A.S. Pribanic
The effects of model compound dopants on the glass transitions of asphalts AAF- 1, AAG-Ĭ, and AAM-1 were measured. Dopants were selected on the basis of molecular size, functional groups, and conformation (linear or branched). Linear hydrocarbon dopants included octadecane (n-C18H38), tetracosane (π-C24Hĵ0), and hexacontane (/i-C60H122). Branched hydrocarbon dopants included pristane
Phytoremediation of crude oil contaminated soil using Sudanese plant species Acacia sieberiana Tausch
Published in International Journal of Phytoremediation, 2023
Amel Hassan Abdallah, Adil Ali Elhussein, Dafaalla Ali Ibrahim
Petroleum hydrocarbon residue was determined in soil samples collected after 180 days from underneath A. sieberiana Tausch seedlings and hydrocarbon degradation percentages were calculated. Degradation percentages obtained, calculated as compared to the control, were in the range of 49–79%. In most cases, degradation percentages were higher at higher crude oil concentrations. Also, it is clear that the highest degradation percentage was recorded for soil collected from underneath A. sieberiana Tausch (79%). Fraction analyses were conducted in plant A. sieberiana Tausch seedlings at intervals of 60, 120 and 180 days of incubation, six different hydrocarbons were detected. The most abundant the hydrocarbon detected were Heneicosane (21 C), Tetracosane (24 C) and Octacosane (28 C) (Table 1).
Comparative performance of a thermal denuder and a catalytic stripper in sampling laboratory and marine exhaust aerosols
Published in Aerosol Science and Technology, 2018
Stavros Amanatidis, Leonidas Ntziachristos, Panu Karjalainen, Erkka Saukko, Pauli Simonen, Niina Kuittinen, Päivi Aakko-Saksa, Hilkka Timonen, Topi Rönkkö, Jorma Keskinen
The TD and CS were challenged with octacosane particles of 120 nm geometric mean diameter. In the TD inlet, the number, volume, and mass concentrations of the hydrocarbon particles were 8 × 105 particles/cm3, 1700 μm3/cm3, and 1.35 mg/m3, respectively, taking into account an octacosane material density of 0.8 g/cm3. Particle concentrations in the CS inlet were approximately 10 times higher. Given the similarity of the hydrocarbon used (octacosane) to the PMP requirements (tetracontane), we can claim that the particle size and number concentration exceeded the PMP requirement of successful evaporation of 30–100 nm particles at a minimum concentration of 104 particles/cm3 (Giechaskiel et al., 2017). Despite the highly concentrated aerosol, both the CS and TD were proven very efficient in practically eliminating all hydrocarbon particles (Figure 2). This is different to the results of Swanson and Kittelson (2010) and Giechaskiel et al. (2009a) who observed tetracosane particles downstream of the TD even when this was challenged with much lower hydrocarbon concentrations (max 380 μm3/cm3) than in the current study. However, in both those studies, the TD operated at 300°C which may have compromised the adsorbing efficiency of the denuding section. This is later discussed in the current study.
Long-acting photocatalytic degradation of crude oil in seawater via combination of TiO2 and N-doped TiO2/reduced graphene oxide
Published in Environmental Technology, 2021
Yinghui Li, Qianqian Zhang, Junxiang Jiang, Ling Li
Graphite powder is chemically pure reagent, neutral alumina is the reagent for chromatography purpose, tetrabutyl titanate and trimethylamine are analytical reagents. The organic solvents including n-hexane, methanol, dichloromethane and chloroform are chromatographically pure reagents. All the above reagents were purchased from Sinopharm Group Chemical Reagent Co., Ltd. (China) and used without further purifications. TiO2 (P25, Degussa). The standard substances for GC-MS measurement are as below: SS EPA 610 PAH Mix (Supelco), Hexamethylbenzene (≥99%, Sigma), Tetracosane-d50 (C24D50, Sigma), C7∼C40 n-Alkane solution (o2si, American).