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Showing 1 to 11 of 11 for “"Naphthenic Acids"”.
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Naphthenic Acids: Synthesis, Characterisation and Factors Influendng Environmental Fate
… to the presence of a class of compounds known as Naphthenic Acids (NAs) which are thought to arise from the biodegradation of some of the crude oil hydrocarbons. Some oils contain as much as 3% by weight NAs. The acids cause engineering and production difficulties through corrosion of refinery …
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Synthesis, Fractionation, Characterisation and Toxicity of Naphthenic Acids from Complex Mixtures
… polluted production waters, complex mixtures of acids, known historically as naphthenic acids (NAs), have achieved prominence. This is particularly because NAs have been designated a toxicant class of concern in the oil sands process-affected water (OSPW) that has accumulated in vast quantities …
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Toxicity, morphological changes, and dissipation of oil sands naphthenic acids in Chlamydomonas reinhardtii
Naphthenic acids fraction components (NAFCs) are a toxic byproduct of oil sands extraction and refining in the Athabasca region of Alberta, Canada, accumulating with other contaminants in the large volumes of oil sands process water produced. NAFCs are incredibly complex mixtures identified as a …
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Evaluation of the immobilized soil bioreactor for treatment of naphthenic acids in oil sands process waters
… oil. Oil sands process water (OSPW) contains naphthenic acids (NAs), a complex mixture of carboxylic acids of the form CnH2n+ZOx that are persistent and toxic to aquatic organisms. Previous studies have demonstrated that aerobic biodegradation reduces NA concentrations and OSPW toxicity; …
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Evaluating the Metal Tolerance Capacity of Oil Sands Tailings Microbes, and their Ability to Degrade Naphthenic Acids While Attached to Biochar
… co-contaminated wastewater treatment; naphthenic acids (NAs, implicated for OSPW toxicity) and metals have been reported in OSPW. This thesis sought to evaluate the metal tolerances of a native OSPW microbial community, and the effect of OSPW-specific metals on their ability to degrade …
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Removal of Naphthenic Acid from Water Using Biomass-based Activated Carbon
… the contaminants found in the produced water are naphthenic acids, naturally occurring compounds in bitumen. Naphthenic acids are a mixture of alkyl-substituted acyclic and cycloaliphatic carboxylic acids. Studies have shown that the concentration of naphthenic acids in tailings ponds and produced …
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State-of-the-art Approaches for Sequencing, Assembling and Annotating Naphthenic Acid Degrading Bacterial Metagenomes
Naphthenic acids (NAs) are the main toxic component of oil refinery wastewater and require special processes to be removed. Harnessing bacterial biodegradation for NA removal has the potential to be effective, yet NA-degrading bacteria and pathways are poorly understood and uncharacterized. To …
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Biogeochemical investigation of centrifuged fine tailings deposits at an oil sands mine in Northern Alberta, Canada
… mg L-1; Cl, 1500 mg L-1; SO4, 5000 mg L-1) and naphthenic acids (NAs 150 mg L-1) near the surface (< 0.3 m) of these deposits. Increases in concentrations of conservative ions (i.e., Cl) indicated that 30 to 40 % of pore water was lost to evaporation at a depth of 0.1 m below surface. Results …
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Multiphase Flow Effects on Naphthenic Acid Corrosion of Carbon Steel
… higher amounts of corrosive sulfur compounds and naphthenic acids (NAP) which, at high velocity multiphase flow conditions, can impair the integrity of transfer lines in crude distillation units. Previous studies have shown that NAP corrosion is particularly aggressive in the presence of a liquid …
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On the bicyclic acids of petroleum
The identification of petroleum acids, also known as ‘naphthenic’ acids (NA), has been an analytical challenge for over 140 years. However, most recent interest in NA has arisen due to concerns over their presence and apparent associated toxic effect in oil platform produced waters and oil sands …
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The Separation of the Polar Constituents of Petroleum
… hydrocarbons; basic nitrogen compounds; naphthenic acids; phenols and other oxygen-containing species; carbazoles; sulfoxides; and thiophenes, to be isolated reproducibly and quantitatively from relatively small crude oil samples (~ 0.5 g). Assessment of method selectivity with a suite of …