Another excellent piece of PTC technology has been innovated by Yoel Sasson’s group in Jerusalem (Dr. Sasson has contributed 40 years of continuous PTC innovation!).
The portion of the patent highlighted here uses phase-transfer catalysis to achieve very effective destruction of halogenated hydrocarbons and other alkyl or aryl halides that can persist as pollutants in groundwater and soil. The technology uses sodium hydroxide and hydrogen peroxide to form superoxide that is brought into contact with the alkyl halide using a phase-transfer catalyst. The technology is fast, quantitative and works at room temperature.
The technology works for alkyl/aryl halide and halogenated hydrocarbon pollutants that are hard to destroy including carbon tetrachloride and chlorobenzene. The table in the diagram shows the results and conditions for several methyl halides.
Several phase-transfer catalysts were screened, including organophilic, hydrophilic and surfactant quats. Aliquat 336 was found to be best.
Another very interesting and useful aspect of this patent is the demonstration of this technology to quantitatively destroy nine different halogenated organics that were absorbed in soil. Full conversion was achieved in 10 minutes at room temperature.
As a reminder, Value Recovery Inc. innovated a PTC scrubber for alkyl halides from the gas phase described in US Patent 7,090,812 (Joyce, Bielski, Buckmaster and Halpern).
If your company seeks quantitative conversion under mild conditions, now contact Marc Halpern of PTC Organics to explore achieving low-cost high-performance green chemistry using phase-transfer catalysis.