The essence of the recent interesting US Patent 9,120,687 (01-Sep-2015) is that Aliquat 336 is an excellent extractant for the thiocyanate anion. In this patent two actions are described: [1] Aliquat 336 is immobilized on a “polymer inclusion membrane” (“PIM”) at a level of 10%-20% and then [2] the PIM is contacted with an aqueous solution containing thiocyanate for the purpose of removing this toxic contaminant from water streams. As we teach in our 2-day course “Industrial Phase-Transfer Catalysis” quaternary ammonium phase-transfer catalysts are highly selective for associating with polarizable anions. Thiocyanate, iodide, perchlorate and permanganate are among the anions with the highest selectivity for quats as shown on this page from our course manual. This is the basis for another patent, US 6,846,946 that extracts these anions from aqueous waste streams and converts them into value added products in one step using phase-transfer catalysis.
The take away message here is that if your company generates or needs to remove polarizable anions from aqueous waste streams, you can use phase-transfer catalysis to very efficiently extract and react these anions to clean up these waste streams and if they are in sufficient quantity, create a valuable marketable product.
If your company has the need to remove byproduct anions from waste streams, now contact Marc Halpern to explore how to integrate the best expertise in industrial phase-transfer catalysis with your requirements.
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!).
