Decision-making and optimization approaches in chemical product/process design often incorporate probability distributions to express uncertainty about the underlying data. We will show in this paper that probabilities are subjective, that they are caused by the decision makers’ lack of confidence in the underlying knowledge, and that the shape of the distribution is affected by psychological input factors. Furthermore, distributions do not necessarily express the range of possible values but rather express the values that are perceived to be possible. Decisions based on distributions can, therefore, be wrong. Screening literature, however, reveals that the origin of risk and uncertainty is not fully understood and should be discussed. To close this gap, we explain where risk, distributions, and probabilities come from. On the basis of these insights, we provide a new optimization framework that describes a process of systematically identifying the optimum alternative by stepwise resolving uncertainty. Finally, we apply the optimization methodology on a case study.

This article describes state-of-the-art investment analysis techniques, shows how and why even reasonably good analyses can lead to bad decisions, and gives guidance on how to avoid mistakes when making investment decisions regarding chemical processes.

Gerald Bode führt moderne Konzepte der Entscheidungstheorie, der wertorientierten Investitionsanalyse und der Beurteilung ökologischer Risiken zu einem neuen, einheitlichen Konzept der risikominimierenden Produkt-/Prozessentwicklung zusammen und kommt zu dem Ergebnis, dass die Beurteilung risikobehafteter Projekte und das Risikomanagement Hand in Hand gehen müssen. Er erläutert die Zusammenhänge zwischen beiden Themengebieten und leitet praktisch nutzbare Maßnahmen zur Reduzierung des F&E- und des Bewertungsrisikos her.

This work examines the reaction kinetics of the syntheses of 1-phenoxyoctane from 1-bromooctane and sodium phenoxide in microemulsions with excess phases. It can be shown that an interfacial reaction model proposed in a previous paper which describes the kinetics of the same reaction in a singlephased microemulsion can also be applied to two-phase systems. In this model the microemulsion is divided into an aqueous and an organic subvolume. The reaction takes place only at the interface between these subvolumes which is covered by a monolayer of surfactant molecules. This study shows that at constant temperatures the reaction rate is proportional to the fraction of surfactant in the microemulsion and therefore to size of the interfacial area. It does not depend on the presence and the size of excess phases.

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