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.
About Marc Halpern
Dr. Halpern is founder and president of PTC Organics, Inc., the only company dedicated exclusively to developing low-cost high-performance green chemistry processes for the manufacture of organic chemicals using Phase Transfer Catalysis. Dr. Halpern has innovated PTC breakthroughs for pharmaceuticals, agrochemicals, petrochemicals, monomers, polymers, flavors & fragrances, dyes & pigments and solvents. Dr. Halpern has provided PTC services on-site at more than 260 industrial process R&D departments in 37 countries and has helped chemical companies save > $200 million. Dr. Halpern co-authored five books including the best-selling “Phase-Transfer Catalysis: Fundamentals, Applications and Industrial Perspectives” and has presented the 2-day course “Practical Phase-Transfer Catalysis” at 50 locations in the US, Europe and Asia.
Dr. Halpern founded the journal “Industrial Phase-Transfer Catalysis” and “The PTC Tip of the Month” enjoyed by 2,100 qualified subscribers, now beyond 130 issues. In 2014, Dr. Halpern is celebrating his 30th year in the chemical industry, including serving as a process chemist at Dow Chemical, a supervisor of process chemistry at ICI, Director of R&D at Sybron Chemicals and founder and president of PTC Organics Inc. (15 years) and PTC Communications Inc. (20 years). Dr. Halpern also co-founded PTC Interface Inc. in 1989 and PTC Value Recovery Inc. in 1999. His academic breakthroughs include the PTC pKa Guidelines, the q-value for quat accessibility and he has achieved industrial PTC breakthroughs for a dozen strong base reactions as well as esterifications, transesterifications, epoxidations and chloromethylations plus contributed to more than 100 other industrial PTC process development projects.
Dr. Halpern has dedicated his adult life to his family and to phase-transfer catalysis (in that order!).
