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Environmental Chemistry Group


chemical glassware in action





 Research Group

Any question? Please contact:
Email: Dr. Carvalho-Knighton

Phone: (727) 873-4063 (Office)
or (727) 873-4833 (Lab)


Current Research Projects

 -Phytoremediation of Explosive Residues


Previous research has shown the possibility of using aquatic plants for the remediation of explosives in contaminated water. The degree of remediation will depend upon the species and amount of aquatic biomass, previous treatment, the contaminant(s) to be removed, concentration of the contaminant(s) and amount and quality of growing water. Aquatic plants have been studied for TNT remediation, but not specifically the phytoremediation of TNT with Lemna minor. Lemna minor was investigated as a possible phytoremediation agent in the removal of TNT from aquatic systems.



 -Zero-Valent Metal Emulsions


Zero-Valent Iron (Fe0) has demonstrated effective degradation of TNT and RDX, however, these particles by themselves have significant problems in treating sorbed phase TNT and RDX in an aerobic environment. This research focuses on emulsifying Fe0 particles that are capable of promoting rapid and complete degradation of TNT and RDX molecules. Fe0 emulsion systems were prepared from weighed portions of Fe0, water, surfactant and other environmentally safe organic liquids and blended together under high sheer forces through the use of a high speed homogenizer.



 -Remediation of PCB's


Remediation of polychlorinated biphenyls (PCBs) has been a major problem in the United States because of their large production volumes in the 1930s and persistence in the environment. Sites contaminated with such compounds may act as long-term, low-level sources (regulatory limits in water are as low as 3.0 ppb) because they desorb slowly from surfaces of soils and aquifer solids or form nonaqueous phases. The characteristics of ZVM treatments (e.g., relatively low installation and operation costs) may also be advantageous for the treatment of contaminants such as polychlorinated biphenyls (PCBs).






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