This paper presents an optimisation approach for determining the best synthesis method and their corresponding operating conditions for synthesising carbon nanotubes for a desired application accounting for technical and economic issues as objective functions. Proper correlations for the interaction between the considered variables are proposed, and these correlations are based on experimental data obtained in the lab. The optimisation formulation is a mixed-integer nonlinear programming problem. A case study considering three synthesis methods of carbon nanotubes (arc discharge, laser ablation and chemical vapour deposition) is presented. High-temperature techniques such as electrical arc-discharge and laser ablation produce CNTs with the highest quality in terms of the graphitic structure; however these techniques are slow and expensive, while the CVD technique is able to produce extremely dense and pure materials, and properties such as crystal structure, surface morphology and orientation of the products can be manipulated and customised via the CVD’s process parameters. The results show that the proposed model can be useful to determine the best method and operating conditions with the maximum efficiency, quality and safety at the minimum cost.
