(674a) Separations: a Short History and a Cloudy Crystal Ball

Separations have played a major role in the history of chemical engineering and will continue to be important in the future. Since separations have always been the major cost item in the process industries, they have always been a key to successful commercialization. Many separation processes such as distillation, adsorption, chromatography and filtration were used long before they were understood. First, the history of the industrial application of separation processes will be briefly reviewed. Next we will review the teaching of separations first as unique to each chemical, next as unit operations, then as part of mass transfer, and finally as separation processes. The perceived shortcomings in the current teaching of separation processes will be briefly discussed.

The second part of the talk will explore predictions for the future of applications, teaching and research in separation processes. These predictions assume that the one great “killer” application that makes a host of existing separation processes obsolete will not appear and that funding for academic research on separations will remain tight.

First prediction: Distillation will remain the major industrial workhorse and a major although perhaps slowly declining part of education in separations. Education in distillation (including absorption and stripping) will increasingly focus on the use of process simulators. Unfortunately, although even small advances in distillations can be economically important and a paradigm shift, although unlikely, would have enormous economic impact, academic research on distillation will remain anemic in the United States.

Second prediction: Extraction will continue to be important in industry and to be covered in undergraduate courses, but not enough time and energy will be focused on the unique extraction design issues in either education or research.

Third prediction: Mechanical separations such as filtration, centrifugation and settling will continue to be ignored in the ChE core although they will remain critically important in industry. Research in particulates will remain reasonably robust.

Fourth prediction: Because of fouling and relatively short lives, membrane separation processes will continue to creep into industrial applications at a slower rate than predicted by researchers. Membrane research will continue to benefit from support that is robust compared to that received by other areas of separation. Membrane separation processes will become an increasingly common part of separation courses in the ChE core.

Fifth prediction: Adsorption, ion exchange and chromatographic separation processes will slowly become more important in industry and will continue to receive modest research support, particularly in biological applications. These processes will be taught mainly at the graduate level. Their lack of coverage at the undergraduate level will continue to serve as a barrier to their wider application in industry.

Sixth prediction: Crystallization, which is critically important in a few industries, will remain an orphan without a home in most core or elective courses. Although crystallization is probably the area of separations where a paradigm shift is most likely to occur, crystallization research is unlikely to receive enough funding to support a paradigm shift.