[en] This work studies various mono substituted aliphatic nitriles, Y C H₂ (Y=H, F, Cl, Br, I, OMe, S Me, SEt₂, Me and Ph), and some reference nitriles (Y=Et, n-Pr, n-Bu, n-Am, n-Hex and n-Hept)

[en] Photochemical transformation of petroleum hydrocarbons, n-alkanes, polycyclic and monoaromatic hydrocarbons under the influence of UV radiation of a mercury lamp have been studied by chromatography and UV spectroscopy. It has been established the kinetic regularities of the formation of abovementioned hydrocarbons within the irradiation up to 90 min at 2x10''15 photon/s UV-light intensity in various concentrations of crude oil up to 5000 ppm on the water surface. A mechanism of possible photochemical processes is discussed. Photochemical degradation of crude oil in an aqueous medium is one of the physicochemical processes, taking place under the influence of UV part of solar radiation and constitutes about 10% of oil conversion in case of oil film on the surface of seawater. Degradation of crude oil occurs under the influence of various physical factors - including the effects of temperature, wind speed, chemical composition and the biological state of seawater. Simultaneous influence of the abovementioned factors makes it very difficult to clarify the mechanism of degradation process of crude oil. Taking into account the abovementioned features of photochemical degradation, it is expedient to study model system consisting of crude oil and distilled water. This work is devoted to the study of photochemical processes under the influence of UV radiation in model system of crude oil-water

[en] According to International Agency for Research on Cancer (IARC), most of Polycyclic Aromatic Hydrocarbons (PAHs) known as genotoxic human carcinogen and mutagenic. PAHs represent as poorly degradable pollutants that exist in soils, sediments, surface water and atmosphere. A simple, rapid and sensitive extraction method termed modified Dispersive Liquid-Liquid Micro extraction (DLLME) using green solvent was developed to determine PAHs in vegetable samples namely radish, cabbage and cucumber prior to Gas Chromatography Flame Ionization Detection (GC-FID). The extraction method is based on replacing chlorinated organic extraction solvent in the conventional DLLME with low toxic solvent, 1-bromo-3-methylbutane without using dispersive solvent. Several experimental factors such as type and volume of extraction solvents, extraction time, confirmation of 12 PAHs by GC-MS, recovery percentages on vegetable samples and the comparative analysis with conventional DLLME were carried out. Both DLLME were successfully extracted 12 types of PAHs. In modified DLLME, the recoveries of the analytes obtained were in a range of 72.72 - 88.07 % with RSD value below 7.5 % which is comparable to the conventional DLLME. The use of microliter of low toxic extraction solvent without addition of dispersive solvent caused the method is economic and environmental friendly which is fulfill the current requirement, green chemistry based analytical method. (author)

[en] The main process used in the bioremediation of contaminated sites is the microbial degradation and mineralization of pollutants. The bioengineering processes developed and applied by the company to optimize the microbial degradation are described and full scale case studies are reviewed. In each case, the site characteristics (type of contaminants, nature of soil, geographic location, etc.) and the results obtained are presented. The selected projects cover different bioremediation techniques (biopile, bioventing and air sparging), different contaminants (PAH, PCP, hydrocarbons) and different types of industrial sites (former gas work plant, petroleum depot, refinery, etc.)

[en] A full-scale demonstration of Grace Dearborn's Daramend trademark for bioremediation of soil containing chlorinated phenols, PAHs and petroleum hydrocarbons is being conducted at an industrial wood treatment site in Ontario. A pilot-scale demonstration of Daramend for the clean-up of sediments contaminated with PAHs was also conducted. The full-scale demonstration, which includes bioremediation of approximately 4,500 m³ of soil, was initiated at a wood preserving facility in Ontario, in the summer of 1993. The soil contains chlorinated phenols, PAHs and total petroleum hydrocarbons at concentrations of up to 700, 1,400 and 6,300 mg/kg respectively. Full-scale bioremediation at this site employs the same Daramend protocols and organic amendment treatments that were used at the pilot-scale phase where the PAH, total petroleum hydrocarbon, and pentachlorophenol concentrations were reduced to below the Canadian clean-up guidelines for industrial soils. In addition, the toxicity of the soil to earthworms was eliminated while the rate of seed germination was increased to that of an agricultural soil during the pilot scale demonstration phase. The ex-situ portion of the full-scale demonstration is currently being audited by the EPA under the SITE program. This paper will focus on the ex-situ work. The pilot-scale demonstration of sediment remediation consisted of ex-situ bioremediation of approximately 90 tonnes of PAH-contaminated sediment in a confined treatment area

[en] Bench-scale treatability investigations, pilot-scale and full-scale bioremediation projects were conducted to evaluate Daramend trademark bioremediation of soils containing petroleum hydrocarbons, heavy oils, paraffins, chlorinated phenols and polycyclic aromatic hydrocarbons (PAHs). Bench-scale investigations were conducted using glass microcosms. Pilot-scale and full-scale demonstrations were conducted at industrial sites and included treatment of excavated soils and sediments in on-site cells constructed using synthetic liners and covered by steel/polyethylene structures as well as in-situ treatment. A total of approximately 5,000 tons of soil was treated. The soil treatment included organic soil amendments, specialized tillage/aeration apparatus, and strict control of soil moisture. The amendments are composed of naturally-occurring organic materials prepared to soil-specific particle size distributions, nutrient profiles, and nutrient-release kinetics. Bench-scale work indicated that in refinery soil containing high concentrations of heavy oils, extractable hydrocarbon concentrations could be rapidly reduced to industrial clean-up criteria, and that the hydrocarbons were fully mineralized with release of CO₂

No abstract available

[en] A study has been carried out to characterize hydrocarbons emitted from the burning of two wood samples that is Kulim (Scorodocarpus spp.) and seraya (Shorea spp.). The woods were burned and respective smoke aerosols emitted were sampled using high volume filtration on a pre-cleaned glass fibre filters under smouldering and flaming conditions. Hydrocarbons were extracted using dichloromethane as solvent and the extracts fractionated on silica-alumina column. Detection and quantification of aliphatic hydrocarbons and PAHs compounds were carried out using GC-MS. Results indicated that the major aliphatic hydrocarbons characterized from the smoke particles were straight n-alkanes in the range of C₁₈-C₃₆. Both samples exhibited an odd to even carbon predominance with carbon preference index (CPI) larger than 1. In general, CPI > 1 indicates n-alkanes contribution from epicuticular waxes and thus it can be concluded that this particular signature of terrestrial plant wax is retained despite the burning process. The total identified n-alkanes for kulim wood was 734 μgg^-1 with C_max at C₂₇ and CPI of 1.10 while seraya wood yielded 113 μgg^-1 total identified n-alkanes with C_max of C₃₁ and CPI of 1.35. Results also indicated that burning resulted in the formation of significant amount of PAHs compounds in both the wood samples; total PAHs compounds emitted from kulim and seraya wood was 5870 μgg^-1 and 5810 μgg^-1, respectively. The major PAHs compound exhibited in both wood samples were four rings PAHs (e.g. fluoranthene and pyrene) with lesser amount of two to three (e.g. acenaphthylene) and five to six rings PAHs (e.g. benzo(a)pyrene and benzo(g,h,i) perylene). In conclusion, burning of wood generated aliphatic and PAHs compounds but their distribution was influenced by the tree species. (author)

[en] For the US Environmental Protection Agency (EPA), the first in-house research effort began in 1987, when results of an early immunoassay field study verified the technology's potential for environmental applications. Looking at the fundamental features of immunochemical reactions from the clinical laboratories, analytical chemists realized the potential value of these methods for hazardous waste site characterization and pesticide monitoring. Immunoassays rely on the interaction between an antibody and a target analyte. For environmental purposes, enzyme immunoassays are generally used. After the target analyte binds to the antibody, an enzymatic reaction yields a colorimetric change. This change, read visually or by a spectrophotometer, indicates the concentration of the target analyte. Promising results with assays for compounds (such as paraquat and pentachlorophenol) and compound groups (such as total petroleum hydrocarbons and polychlorinated biphenyls) spurred interest among various entrepreneurs. The first target market for immunoassays was environmental engineers and field crews who needed quick answers on-site to determine the direction of further remediation efforts

[en] Ion-chromatographic technique has been employed to estimate the halide ion yield formed on reaction of e_aq^- and ^?OH radicals with 1-fluoro-n-iodobenzene, 1-bromo-n-iodobenzene, 1-fluoro-n-bromobenzene, 1-chloro-n-iodobenzene (n=2,3,4). The halide ion yield is observed to depend upon bond strength, electron affinities and relative positions of halogen on the benzene ring. Radiation chemical yields of the halide ion are compared for a pair of halogen atoms with respect to their relative position. The inter comparison of yields for similarly substituted different halogen has also been carried out