(46d) Developing Sustainable Chemical Processes: An Integrated Approach Involving Concurrent Catalyst, Media and/or Reactor Innovations

The increased need for sustainable chemical manufacturing processes provides many challenges/opportunities for developing novel technologies [[1]].  Sustainable alternatives to conventional chemical technologies can be developed by either developing greener process technologies based on existing feedstocks or by replacement of fossil based feedstocks with renewable ones such as those derived from biomass. Processing renewable feedstocks to produce chemicals not only requires the development of new chemistries but it is also imperative that the new conversion technologies are sustainable to preserve the “green” potential of biomass based feedstock.

At the CEBC, an integrated approach that fully exploits the synergies between catalyst design, tunable reaction media (such as supercritical fluids, gas-expanded liquids, ionic liquids) and novel reactor concepts (integrating reaction and separation) has been employed to developed alternate technology concepts for a variety of industrially important reactions.  The demonstrated advantages include process intensification at mild conditions, enhancing process safety by elimination of flammable vapor phases, and waste mitigation by reduced usage of organic solvents and suppression of side reactions that generate undesired byproducts such as CO₂.  Specific examples of novel process concepts to be discussed include the highly selective hydroformylation of higher olefins at mild conditions employing soluble polymer-attached Rh catalysts that are easily retained in solution while the product is isolated by membrane filtration [[2]]; a novel homogeneous ethylene oxide process virtually eliminating CO₂ formation as a byproduct [[3]]; and a one-step spray reactor concept to overcome gas-liquid transport limitations for the inherently-safe formation of polymer-grade terephthalic acid from p-xylene at high yields and purity [[4]]. The significant role of quantitative sustainability analyses (economic and environmental impact) in guiding the development of these processes will also be discussed.

References