**Appendix A**

Operating conditions of the LLE proved critical to optimizing organic extraction. For these extractions the heavy solvent valve was closed. Carbon-treated feed was first charged into the extraction column. Then the remaining height of the extraction column was filled with MTBE. To control the ratio of solvent to feedstock, the remaining quantity of MTBE was then charged into the collection flask. Once charged, the glass fittings were all sealed with vacuum grease and clamps. The circulator for the condenser was set to 5 ◦C and allowed to equilibrate before starting heating. A stir bar and plate with no heating provided mixing to the extraction column, while a stir bar and plate with heating via mineral oil bath provided heat and mixing to the collection flask. A low flow of N2 was applied to the head space above the condenser to minimize loss of material during extraction. Once equilibrated at ambient temperature the mineral oil bath was heated to 80 ◦C; this vaporized the MTBE from the collection flask to the condenser, where it condensed and ran down a drip tube to the bottom of the extraction flask. As the MTBE rose through the extraction flask it extracted the target organics from the feedstock. Upon reaching the top of the extraction flask, the organic rich MTBE then flowed back to the collection flask where the MTBE vaporized again but the other organics did not. This stable cycle of the LLE was then continued for ~48 h.
