PhD Proposal: Yu Ting

Yu Ting, PhD Student

Location: Technology Research Center 206 & WEBEX

Advisor

Dr. Upal Ghosh

Dr. Kevin Sowers, Co-Advisor

Title:

Sorption-mediated halorespiration biokinetics of organochlorines

Abstract:

Organochlorines (OCs) in aquatic environments can be dechlorinated by organohalide-respiring bacteria (OHRB) that utilize OCs as electron acceptors under anaerobic conditions. Bioaugmentation by addition of OHRB to OCs-contaminated sites accelerates halorespiration of OCs. Alternatively, sorbent amendment reduces the bioavailability of OCs by sequestrating them in the sorbed phase, which further reduces their bioaccumulation in fauna and flora. More recently, an emerging concept of combining microbial bioaugmentation and sorbent amendment, is being explored as a strategy for OC cleanup in recalcitrant sites. However, the lack of fundamental understanding of how material surfaces interact with microorganisms limits our ability to engineer novel remediation technologies.

This research aims to develop a mechanistic understanding of how black carbon sorbents impact the outcomes of the OC bioremediation in soils and sediments. This goal will be pursued using the cross-comparison of microcosm data and kinetic model simulation results. Methodologies will be developed to allow quantification of biokinetics for the OHRB biofilms on carbon-based sorbent materials. The challenges of attaching cells to the solids and compensating for the extra variables introduced by sorption will also be addressed. The established methodologies will be used to understand how solid surface physicochemical properties may impact microbial halorespiration biokinetics. Solid materials such as graphite and activated carbons with various surface properties will be tested. The fate and distribution of OHRB cells spreading from the original biosorbents to surrounding environmental matrices will be quantitatively characterized. An integrated model will be established based on the knowledge gained from the results to predict the mass transfer of different OCs in the sediment under remediation scenarios. The knowledge acquired in this study will be the foundation for accurately predicting the field performance of bioremediation and advancing future sediment remediation design by optimizing material properties, dose, scale-up, and transition to the field.

Agenda

• 11:55 am: Meeting room will open
• 12:00 pm: 45-min presentation will be open to the public with Q&A.
• Followed by a closed session with the committee and PhD Student.