Partitioning Coefficients of BTEX Compounds Between NLF Leachate and Water Jeremy T. Roop Dr. Mark A. Nanny Crystal K. Stearns

Overview Background Goal Experimental Designs Results/future research

Background Norman landfill Older landfill Inadequate liner Development of leachate plume BTEX Benzene, Toluene, Ethylbenzene and Xylene Hydrophobic, Toxic and Soluble

Background (cont.) BTEX compounds Paints, solvents and gas Present in NLF and other older municipal landfills

Goal: To quantify the partitioning coefficients of BTEX compounds between organic matter present in NLF leachate and water

How does organic matter in leachate interact with BTEX compounds? BTEX partitions to organic matter Def. Partitioning Why is it important to quantify partitioning coefficients? Shows partitioning to organic matter vs. partitioning to water Allows prediction of chemical fate in environment

Solid Phase Microextraction Technique used to measure free concentrations in solution How it works Analytes in solution partition to wick and equilibrium is reached Once at equilibrium, amount on wick is constant Wick can be exposed to GC for desorption

Benefits of SPME Time saving Accurate Doesn’t involve solvents Relatively inexpensive

Experimental Design Goal: Quantify partitioning coefficients Concept Prepare solutions with various different leachate/toluene ratios Determine amount of toluene partitioning by measuring free concentrations Plot data Free concentration vs. toluene/leachate ratio Take slope of best fit line

Preliminary Results Good data

Effects of Saturation Runs with leachate Saturated salt solutions effect sensitivity of SPME method Increased conductivity of leachate was increasing sensitivity of method

Experimental Design II Added NaCl to adjust conductivity of control samples Preliminary data was good

More complications Not reproducible Increasing saturation of solution may effect kinetics of wick

Results and Conclusions SPME is a good technique Capable of accuracy Lots of variables Saturated salt solutions greatly effect sensitivity and accuracy of SPME

Future Research Explore effects of conductivity on SPME technique Fulvic acid experiment Plenty of time Automation-eliminate error and save time Newer equipment, capable of greater degree of consistency

Acknowledgements Dr. Mark A. Nanny and Crystal K. Stearns Dr. Kolar, Lisa Hare, Erin Breetzke and OU REU NSF EEC