The McCabe–Thiele Method: A Centenary Tribute to an Emblem of Chemical Engineering and Engineering Epistemology

This essay is a tribute to the McCabe–Thiele method, which was first published 100 years ago in this journal. We argue that the McCabe–Thiele method has become an emblem of chemical engineering, as it establishes a balance that simultaneously enables prediction and understanding, making it also emblematic of engineering epistemology. The McCabe–Thiele method is analyzed here by going through its most important aspects: the historical background, the model assumptions and how these enable predictions and understanding, as well as the question of novelty. We argue that the remarkably long-lasting success of the McCabe–Thiele method is due to how it creates understanding through its graphical approach, and we identify elements of engineering epistemology that make it emblematic in a quite general sense. Finally, we briefly discuss the future role of the McCabe–Thiele method, considering that machine learning will change the way distillations are designed.