Presidential Green Chemistry Challenge Alternative

The newer Flexsys patented process shown in Figure 11.21 is much more efficient than the older synthesis routes, with a 95% reduction in waste. There is no production of hydrochloric acid byproduct, and there is no need for the use of chiorinated benzene feedstocks. This process received the Environmental Protection Agency s Presidential Green Chemistry Challenge Alternative Synthetic Pathways Award, and Flexsys spent about 70 million on the construction of a new piant for this PPD2 process in Antwerp, Belgium. 

In 1992 BHC (Boots Hoechst-Celanese) Company commercialized a new synthetic process to manufacture ibuprofen in BHC s 3500 metric-ton-per-year facility in Bishop/TX, USA, which was cited as an industry model of environmental excellence in chemical processing technology. For its innovation, BHC was the recipient of the 1997 Alternative Synthetic Pathways Award of the Presidential Green Chemistry Challenge. 

This manufacturing process received the Presidential Green Chemistry Challenge Award (2006) for alternative synthetic pathways, the IChemE AstraZeneca Award for excellence in green chemistry and chemical engineering (2005), and the Thomas Alva Edison Patent Award (2009) for Merck s U.S. Pat. 7,468,459. 

In 1991, Barry Trosfl introduced the concept of atom economy (for which he received a Presidential Green Chemistry Challenge Award ). The essence of this concept is the notion that another useful way to measure the success of a chemical synthesis is to consider the fate of all of the reactant atoms (apart from solvent). For example, if a catalyst is used to simply facilitate a rearrangement of molecules with 100% conversion (and the catalyst can be recycled with 100% recovery), then all of the atoms in the reactant molecule wiU end up on the product molecule. This is 100% atom economy. Alternately, an elimination reaction will necessarily have less than 100% atom economy since the atoms eliminated from the reactant represent waste. ... 

U.S. Bureau of Engraving, ISOMET Development of an alternative solvent. The Presidential Green Chemistry Challenge Awards Program, summary of 1999 award entries and recipients, EPA744-R-00-001, 1999. 

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