Advanced search options

Advanced Search Options 🞨

Browse by author name (“Author name starts with…”).

Find ETDs with:

in
/  
in
/  
in
/  
in

Written in Published in Earliest date Latest date

Sorted by

Results per page:

Sorted by: relevance · author · university · dateNew search

You searched for subject:(Vegetable Oil Spills). Showing records 1 – 2 of 2 total matches.

Search Limiters

Last 2 Years | English Only

No search limiters apply to these results.

▼ Search Limiters


University of Cincinnati

1. Salam, Darine. Fate and Impacts of Vegetable Oil Spills in Aquatic Environments.

Degree: PhD, Engineering and Applied Science: Environmental Science, 2011, University of Cincinnati

The kinetics and ecological impacts of the aerobic biodegradation of vegetable oils in contaminated aquatic environments were studied in respirometric microcosms at different oil loadings (100, 333, and 1,000 gal acre-1) and mixing regimes (fully, moderately, and non-mixed microcosms). No significant difference in the extent of oil biodegradation was observed between the fully and moderately mixed microcosms at 100 and 333 gal acre-1 loadings, indicating minimal influence of enhanced mixing in these cases. Furthermore, comparable oxygen uptake rates were measured initially in the moderately and non-mixed microcosms at the 100 and 333 gal acre-1 loadings, suggesting an initial dependence of the microbial activity on the oil surface available for emulsification rather than on the oil concentration. Regardless of the mixing condition, reduced initial oxygen uptake rates were measured at 1,000 gal acre-1 loading and were associated with an initial oxygen mass transfer limitation. The results of the Microtox┬« assay showed no major toxicity at the 100 gal acre-1 loading. Furthermore, oxygen was not completely depleted from the water column at this oil coverage. At higher oil loadings, oxygen was fully depleted from the mixed and non-mixed water columns. A transient toxicity in the aqueous phase was observed in the case of the moderately mixed microcosms at 333 gal acre-1 and was maintained at moderate levels (EC50 ~30%) in the non-mixed microcosms. A substantial increase in toxicity (EC50 ~10 %) was observed in both mixing conditions when the initial oil loading was increased to 1,000 gal acre-1. Furthermore, the effect of antioxidants on the fate and impacts of vegetable oils in contaminated aquatic media was investigated. Respirometric experiments on the effect of increasing concentrations of butylated-hydroxytoluene (BHT) (0, 50, 100, 200, 400, and 800 ppm) on the biodegradability of glyceryl trilinoleate (333 gal acre-1), revealed the formation of intractable rigid polymers unavailable for bacterial degradation in all BHT treatments and particularly in the microcosms not supplemented with the antioxidant. In this case, limited oil mineralization was observed after 19 weeks of incubation (41%) compared to the microcosms supplemented with BHT (> 67 %). In these microcosms, no significant difference in the achieved oil mineralization was observed with increasing BHT concentrations, suggesting minimal additional protective effect of BHT above 50 and up to 800 ppm.In addition, the effect of BHT on the biodegradability and toxicity of purified canola oil (333 gal acre-1) was investigated in the absence and presence (200 ppm) of the antioxidant. Substantial oil mineralization was achieved after 16 weeks of incubation (> 77%) and was not significantly different between the two BHT treatments. Furthermore, for both treatments, a transient toxicity was observed and was attributed to the combined effect of toxic biodegradation intermediates and autoxidation products. Autoxidation in the microcosms initially supplemented with the… Advisors/Committee Members: Suidan, Makram (Committee Chair).

Subjects/Keywords: Sanitation; Vegetable Oil Spills; Aerobic Biodegradation; Autoxidation; Polymerization

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Salam, D. (2011). Fate and Impacts of Vegetable Oil Spills in Aquatic Environments. (Doctoral Dissertation). University of Cincinnati. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ucin1321367790

Chicago Manual of Style (16th Edition):

Salam, Darine. “Fate and Impacts of Vegetable Oil Spills in Aquatic Environments.” 2011. Doctoral Dissertation, University of Cincinnati. Accessed December 13, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1321367790.

MLA Handbook (7th Edition):

Salam, Darine. “Fate and Impacts of Vegetable Oil Spills in Aquatic Environments.” 2011. Web. 13 Dec 2019.

Vancouver:

Salam D. Fate and Impacts of Vegetable Oil Spills in Aquatic Environments. [Internet] [Doctoral dissertation]. University of Cincinnati; 2011. [cited 2019 Dec 13]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1321367790.

Council of Science Editors:

Salam D. Fate and Impacts of Vegetable Oil Spills in Aquatic Environments. [Doctoral Dissertation]. University of Cincinnati; 2011. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1321367790

2. Dos Santos Pereira, Maria da Gloria. Bacterial degradation of linseed and sunflower oils in salt marsh sediments.

Degree: PhD, 1999, Bangor University

This work investigated the consequences of vegetable oils spills in salt marsh sediments. The role of autochthonous bacteria in the oils degradation and degradative pathways were also studied 'in situ' and 'in vitro'. Simulated spills of sunflower and linseed oils revealed that both oils penetrated the sediments at a rate of 10-7 CM2 s-1. However, whereas 60% of the linseed oil had disappeared from the sediments after 2 months most of the sunflower oil remained after 6 months. Differences were noted in the adsorption of the oils to sediment particles and the depth at which they accumulate and these factors most likely influenced the route of the oil degradation and the sediments properties such as permeability. The contamination of the sediments with vegetable oils lead to a noticeable reduction in the abundance of plant roots and infauna. The abundance of aerobic, anaerobic and sulphate reducing bacteria in the sediments was increased by the addition of both oils, with linseed oil supporting greater bacterial density than sunflower oil. During the course of the experiment the relative abundance of oil degrading bacteria also increased. As a consequence of the increased bacterial activity, the sediments pH and Eh decreased and anoxic conditions were established, earlier in the case of linseed than that of sunflower oils. The degradation of the oils appeared to be a sequential process, initiated by the aerobic and/or anaerobic bacteria and continued by the sulphate reducing bacteria which themselves where unable to utilise the raw oils. The original composition of both oils underwent alterations mostly associated with their main fatty acid: the concentration of 18: 3(o3 and 18: 2o)6 in linseed and sunflower oil, respectively, decreased whereas that of the remaining fatty acids increased. As a result of the bacterial degradation of the vegetable oils 'new' fatty acids were detected and their identification was attempted using GC-MS analysis of their picolinyl and methyl esters. Various degradative pathways of linseed and sunflower oils involving the formation of the 'new' fatty acids are suggested with isomerisation, hydrogenation and P-oxidation as the primary routes for the degradation.

Subjects/Keywords: 628.168; Vegetable oil spills; Fatty-acids

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Dos Santos Pereira, M. d. G. (1999). Bacterial degradation of linseed and sunflower oils in salt marsh sediments. (Doctoral Dissertation). Bangor University. Retrieved from https://research.bangor.ac.uk/portal/en/theses/bacterial-degradation-of-linseed-and-sunflower-oils-in-salt-marsh-sediments(4697b1cb-815d-46a6-8b52-880c0cfcf62c).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285488

Chicago Manual of Style (16th Edition):

Dos Santos Pereira, Maria da Gloria. “Bacterial degradation of linseed and sunflower oils in salt marsh sediments.” 1999. Doctoral Dissertation, Bangor University. Accessed December 13, 2019. https://research.bangor.ac.uk/portal/en/theses/bacterial-degradation-of-linseed-and-sunflower-oils-in-salt-marsh-sediments(4697b1cb-815d-46a6-8b52-880c0cfcf62c).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285488.

MLA Handbook (7th Edition):

Dos Santos Pereira, Maria da Gloria. “Bacterial degradation of linseed and sunflower oils in salt marsh sediments.” 1999. Web. 13 Dec 2019.

Vancouver:

Dos Santos Pereira MdG. Bacterial degradation of linseed and sunflower oils in salt marsh sediments. [Internet] [Doctoral dissertation]. Bangor University; 1999. [cited 2019 Dec 13]. Available from: https://research.bangor.ac.uk/portal/en/theses/bacterial-degradation-of-linseed-and-sunflower-oils-in-salt-marsh-sediments(4697b1cb-815d-46a6-8b52-880c0cfcf62c).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285488.

Council of Science Editors:

Dos Santos Pereira MdG. Bacterial degradation of linseed and sunflower oils in salt marsh sediments. [Doctoral Dissertation]. Bangor University; 1999. Available from: https://research.bangor.ac.uk/portal/en/theses/bacterial-degradation-of-linseed-and-sunflower-oils-in-salt-marsh-sediments(4697b1cb-815d-46a6-8b52-880c0cfcf62c).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285488

.