Computer-aided molecular design in the continuous-molecular targeting framework using group-contribution PC-SAFT

• A framework for the integrated design of fluids and processes is presented.
• Computer-aided molecular design based on group-contribution PC-SAFT (GPC-SAFT).
• Designed fluids are assessed with a process-level objective function.
• We demonstrate the proposed approach in two important areas of fluid design.

Computer-aided molecular design allows generating novel fluids fulfilling a set of target properties. An integrated design of fluid and process directly employs a process-based objective function. In this work, we solve the integrated process and fluid design problem using the continuous-molecular targeting computer-aided molecular design (CoMT–CAMD) framework. CoMT–CAMD exploits the molecular picture underlying the PC-SAFT equation of state. In the simultaneous optimization of process and fluid, relaxed pure component parameters allow for an efficient optimization. The result is a hypothetical optimal target fluid. In previous work, fluids showing similar performance as the target fluid were obtained from a mapping onto a database. Here, we integrate computer-aided molecular design to realize the actual design of novel fluids. The resulting method for fluid design is based on a group-contribution method for the PC-SAFT parameters (GPC-SAFT) and applied to the design of working fluids for Organic Rankine cycles and solvents for CO2 capture.