Distribution of PAHs in Surface Soils from Petroleum Handling Facilities in Calabar

The level of concentrations of polycyclic aromatic hydrocarbons (PAHs) in surface soils from petroleum handling facilities (kerosene tank, generating plant, petrol stations, mechanic workshops, leaking pipeline and air port fuel dump) from Calabar metropolis southeastern Nigeria was determined by gas chromatography/ mass spectrometry. The results show that total polycyclic aromatic hydrocarbons (PAHs) varied from 1.80 to 334.43 mg/kg with a mean of 50.31 mg/kg. The lowest value of 1.80 mg/kg was obtained from petrol station while the highest value of 334.43 mg/kg was obtained from facility characterised by petrol stations and mechanic workshops. The ratio of phenanthrene/anthracene and fluoranthene/pyrene, varied from 0.43 to 27.72 and from 0.14 to 17.76 respectively. These ratios indicate various sources for the PAH. The two to three ring PAHs are the most abundant. Based on the PAH ratios and content alone it is not possible to distinguish between contribution from motor vehicle exhaust, gasoline spillage, used engine oil or petroleum production. However, considering the area of the study, it is very likely that the major source of soil contamination is originating from petroleum product.     

Emission factors of particulate matter, CO and CO2 in the pyrolytic processing of typical electronic wastes

A self-designed experimental device was employed to simulate the pyrolytic dismantling process of selected electronic wastes(E-wastes), including printed wiring boards(PWBs)and plastic casings. The generated particulate matter(PM) of different particle sizes, carbon monoxide(CO) and carbon dioxide(CO_2) were determined, and the corresponding emission factors(EFs) were estimated. Finer particles with particle sizes of 0.4–2.1 μm accounted for78.9% and 89.3% of PM emitted by the pyrolytic processing of PWBs and plastic casings,respectively, and the corresponding EFs were 9.68 ± 4.81 and 18.49 ± 7.2 g/kg, respectively.The EFs of CO and CO_2 from PWBs and plastic casings were 55.9 ± 26.9 and 1182 ± 439 g/kg,and 133.6 ± 34.6 and 2827 ± 276 g/kg, respectively. Compared with other emission sources,such as coal, biomass, and traffic exhaust, the EFs of E-wastes were relatively higher,especially for PM. There were significant positive correlations(p 0.05) of the initial contents of carbon and nitrogen in PWBs with the related EFs of PM, CO, and CO_2, while the correlations for plastic casings were insignificant. The EFs of CO of PWBs were significantly positively correlated with the corresponding EFs of PM and the parent polycyclic aromatic hydrocarbons(PAHs); however, the same result was not observed for plastic casings.     

Brazilian Oil Spills Chemical Characterization--Case Studies

In the last decade, PETROBRAS has experienced some significant oil spills cases and the PETROBRAS Research Center has played an important role in the company emergency response program by characterizing the spilled oil, monitoring the affected ecosystem, determining the fate of the oil in the environment, and, subsequently, helping the company in assessing the environmental damage. This paper presents the use of advanced chemical analytical techniques (GC/FID, P&T/GC/PID and GC/MS) in some Brazilian oil spill studies in order to determine fractions and individual petroleum hydrocarbons in different matrices such as water, groundwater, sediment, sand, fish and the spilled oil itself. The spill studies encompassed crude and fuel oil releases on land and coastal ecosystems, related to the incidents in Guanabara Bay (Rio de Janeiro), Barigui and Iguassu Rivers (Parana) and Sao Sebastiao Channel (Sao Paulo). Total petroleum hydrocarbons (TPH), n -alkanes, isoprenoids, unresolved complex mixtures (UCM), volatile monoaromatic compounds--benzene, toluene, ethylbenzene and xylenes (BTEX), parent and alkylated homologues polycyclic aromatic hydrocarbons (PAH), and terpanes and steranes were characterized for determining correlation to the spilled oil and other known oil sources and environmental assessment. Some of the acute ecotoxicity data for water and sediment samples is also presented.     

Biochars derived from carp residues: characteristics and copper immobilization performance in water environments

● P-rich carp residues-derived biochars presented excellent Cu sorption capacity. ● Sorption mechanisms of Cu on CRBs were mainly precipitation and surface complexation. ● CRBs could immobilize Cu and reduce its bioavailability in aquatic environment. Heavy metal pollution has attracted worldwide attention because of its adverse impact on the aquatic environment and human health. The production of biochar from biowaste has become a promising strategy for managing animal carcasses and remediating heavy metal pollution in the aquatic environment. However, the sorption and remediation performance of carp residue-derived biochar (CRB) in Cu-polluted water is poorly understood. Herein, batches of CRB were prepared from carp residues at 450–650 °C (CRB450–650) to investigate their physicochemical characteristics and performance in the sorption and remediation of Cu-polluted water. Compared with a relatively low-temperature CRB (e.g., CRB450), the high-temperature biochar (CRB650) possessed a large surface area and thermodynamic stability. CRB650 contained higher oxygen-containing functional groups and P-associated minerals, such as hydroxyapatite. As the pyrolytic temperature increased from 450 to 650°C, the maximum sorption capacity of the CRBs increased from 26.5 to 62.5 mg/g. The adsorption process was a type of monolayer adsorption onto homogenous materials, and the sorption of Cu²⁺ on the CRB was mainly based on chemical adsorption. The most effective potential adsorption mechanisms were in order of electrostatic attraction and cation-π interaction > surface complexation and precipitation > pore-filling and cation exchange. Accordingly, the CRBs efficiently immobilized Cu²⁺ and reduced its bioavailability in water. These results provide a promising strategy to remediate heavy metal-polluted water using designer biochars derived from biowastes, particularly animal carcasses.