Systematic Model-Based Methodology for Substitution of Hazardous Chemicals

Driven by obligations to comply with the regulations and various public policies, substitution of chemicals with safer counterparts is now being widely practiced by industry. In this paper, the development of a systematic model-based methodology for chemical substitution is described. The methodology considers different problem definitions depending on the “objective for substitution”.

A general framework, which includes the algorithm steps of the methodology, corresponding data flow, associated property models, databases, and modeling tools for generating and evaluating the substitute candidates, is presented. The application of the developed methodology is highlighted through four case studies on substitution of “chemicals of concern” used in chemical-based products or in processes and their operation.

The alternative chemicals are found by matching the desired properties related to the physicochemical nature, function, and performance of the chemical being substituted, while avoiding its undesired, environmental, health, and safety-related properties. The objective of developing this methodology for chemical substitution is to quickly and reliably identify the promising candidates through model-based techniques, check their economic feasibility, and only then proceed to conduct experiments to verify their compatibility and applicability.

In this way, the experimental resources are used only for verification rather than for an inefficient, trial-and-error, and sometimes time-consuming and expensive search for substitute candidates.