Whatsoever things are true: Hypothesis, artefact, and bias in chemical engineering research

For experimental research to offer valuable insights and predictions, its results and interpretation need to be properly validated. When the experiments deal with complex systems, such as biological materials, multicomponent mixtures, or multiple phases, the use of the rigorous scientific method is essential. Setting and testing hypotheses and design of experimental programs to include formal positive and negative experiments helps to identify artefacts and to minimize the influence of the biases of the investigators that can invalidate the results of studies. The literature has many examples of well‐executed studies, but there is much less discussion of the pitfalls and traps that can beset experimental research. This paper presents cases in the area of chemical reaction engineering and biochemical engineering. Experimental designs are presented that were successful in validating results by using positive and negative controls. Case studies of experimental artefacts that were published suggest that the biases of the investigators were important in failing to fully verify experimental observations. Both strong experimental designs to identify artefacts and publication of negative results are important in avoiding the persistence of what Stephen Poole calls “zombie ideas”. These zombie ideas may be benign, or they may lead to considerable wasted effort on studies with no chance of success. Graphical representations and schematics are extremely valuable in communicating results and making them memorable, but they can also be seductive in misleading researchers.