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1

Kinetics of degradation of perchloroethylene under ultrasonic irradiation and photooxidation in aqueous solution

Kargar M., Nabizadeh R., Naddafi K., Nasseri S., Mesdaghinia A., Mahvi A. H., Alimohammadi M., Nazmara S.

Environment Protection Engineering

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2013

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Vol. 39, nr 4

29--38

EN

Sonolysis and photodegradation of various compounds such as chlorinated aliphatic hydrocarbons are the recent advanced oxidation processes. Perchloroethylene PCE is one of these compounds mainly used as a solvent and degreaser. In this work, elimination of perchloroethylene in aqueous solution by ultrasonic irradiation and photooxidation by UVC were investigated. Head space gas chromatography with FID detector was used for analyses of PCE. Results showed that PCE could be effectively and rapidly degraded by ultrasonic irradiation, photooxidation by UVC and combination of these methods. The order of studied reactions for degradation PCE has been determined.

2

Zastosowanie surfaktantów niejonowych do usuwania zanieczyszczeń chloroorganicznych z gleby

Pastewski S., Potkańska M., Mędrzycka K.

Inżynieria i Aparatura Chemiczna

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2009

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Nr 5

88-89

PL

Zbadano solubilizację micelarną tetrachloroetylenu w roztworach al-kilopoliglukozydów (Triton BG10 i AG (>210). Przeprowadzono procesy przemywania gleby zanieczyszczonej tetrachloroetylenera przy użyciu roztworów alkilopoliglukozydów oraz oksyetylenowanych alkoholi (Rokanole NL5, NL6, NL8, L7, L10). Określono wpływ hydrofilowości surfaktantu i jego stężenia na efektywność przemywania gleby.

EN

Micellar solubilization of tetrachloroethylene in solutions of alkylpoly-glucosides (Triton BG10, AC 6210) and ability of alkylpolyglucosides and polyethoxylated alcohols (Rokaiiol NL5, NL6, NL8, L7, L10) for removal of tetrachloroethylene from soil were investigated. Influence of hydrophilicity of surfactants and their concentration in solution on washing efficiency was investigated.

3

Monitoring subsurface microbial ecology and demonstrating in situ biodegradation potential using Bio-Sep® Bio-traps

Busch-Harris J. L., Jennings E., Sublette K.L., Roberts K. P., White D. C., Peacock A., Davis G., Ogles D., Holmes W. E., Yang X, Kolhatkar A., Beckmann D., Kolhatkar R.

Chemia i Inżynieria Ekologiczna

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2006

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Vol. 13, nr 5

349--372

EN

Monitored natural attenuation can be a successful management strategy for groundwater contamination if requisite microbial and geochemical conditions are present. Subsurface microbial ecology of a contaminated aquifer is often investigated by sampling groundwater from the plume. However, the subsurface microbial ecology of a contaminated aquifer is better represented by in situ biofilms than planktonic organisms. Conventional sampling to collect the sessile subsurface microbial community requires coring of the aquifer sediments. However, the efficiency of extracting viable microorganisms and biomarkers from these sediments varies with site geochemistry. Therefore, we have developed a rapid and efficient microbial-sampling system based on Bio-Sep® technology. Bio-Sep® consists of 3-4 mm diameter spherical porous beads engineered from a composite of 25 % aramid polymer and 75 % powdered activated carbon. These beads encourage microbial growth by providing high internal surface area with low-shear conditions, and by concentrating limiting nutrients within the groundwater environment. Biomarkers can be efficiently extracted from Bio-Sep® to provide measures of viable biomass, redox environment, and microbial community composition. We have introduced Bio-Sep® beads into aquifers contaminated with tetrachloroethylene, BTEX, MTBE, and uranium where we used Bio-Sep® to evaluate the effects of potential remediation amendments and to demonstrate in situ biodegradation. This paper presents a review of the Bio-Sep technology, and its applications for documenting subsurface microbial ecology and bioprocesses in contaminated aquifers.

PL

Monitoring fauny bakteryjnej obecnej w wodach podziemnych jest dogodnym narzędziem w ocenie jakości środowiska. Tradycyjne techniki pobierania próbek wód podziemnych oraz osadów wymagają wykonania odwiertów w celu pobrania żyjących w wodzie mikroorganizmów. W pracy przedstawiono szybki i sprawny system pobierania próbek mikrobowych, korzystający z technologii Bio-Sep®, składający się z kulek porowatych o średnicy 3-4 mm, stwarzających dogodne warunki do wzrostu mikroorganizmów. Kulki Bio-Sep®, zostały wprowadzone do wód zanieczyszczonych tetrachloroetylenem, BTEX, MTBE oraz uranem. W pracy zaprezentowano technologię Bio-Sep® oraz jej zastosowanie.

4

Catalytic oxidation of volatile chlorinated hydrocarbons.

Szechy G., Szabo S., Bajnoczy G.

Prace Naukowe Instytutu Chemii i Technologii Nafty i Węgla Politechniki Wrocławskiej. Konferencje

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2002

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Vol. 10, nr 57

163-168

EN

Catalysts containing Ru on a TiO2- containing support or pure TiO2 were tested in the conversion of trichloro-ethylene (TCE) Increase of the TiO2 content of the support from ~20 to ~100%, or introduction of Ce as a second active component did not bring any advantage compared to the previously studied Ru-SM1 (Ru on ~20% TiO2 + 80% SiO2). Parameter tests were carried out in the presence of the latter catalyst. Total conversion of TCE was achieved at 450°C. Water vapor concentration practically did not affect the conversion of TCE. Higher space velocities have shifted the product, distribution towards HCl. Higher inlet concentrations of the model compound have resulted in decreased catalyst activity. 1,2-dichloroethane was easier to convert than TCE or tetrachloro-ethylene.

5

Interactions of Some Organic Solvents: Hydrocarbons and Chloroalkene

Skowroń J., Miranowicz-Dzierżawska K., Zapór L., Gołofit-Szymczak M., Starek A.

International Journal of Occupational Safety and Ergonomics

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2001

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Vol. 7, No. 1

35--47

EN

Metabolic and toxicodynamic interactions of some organic solvents in rats repeatedly treated with medium dose levels were examined. It was shown that both n-hexane and ethylbenzene significantly inhibited tetrachloroethylene metabolism during a 2-week period. n-Hexane and tetrachloroethylene enhanced metabolism of ethylbenzene whereas ethylbenzene suppressed n-hexane metabolism only at the end of the experiment. Biochemical changes, especially the drop in the level of non-protein sulfhydryl groups in tissues of rats treated with organic solvent mixtures, were significantly less pronounced than those observed after these chemicals were administered separately. These results demonstrate that metabolic interactions between hydrocarbons and chloroalkene may lead to a modification of the biological response to these compounds.