Systematic Selection of Green Solvents and Process Optimization for the Hydroformylation of Long-Chain Olefines

Abstract

Including ecologic and environmental aspects in chemical engineering requires new methods for process design and optimization. In this work, a hydroformylation process of long-chain olefines is investigated. A thermomorphic multiphase system is employed that is homogeneous at reaction conditions and biphasic at lower temperatures for catalyst recycling. In an attempt to replace the toxic polar solvent N,N-dimethylformamide (DMF), ecologically benign alternatives are selected using a screening approach. Economic process optimization is conducted for DMF and two candidate solvents. It is found that one of the green candidates performs similarly well as the standard benchmark solvent DMF, without being toxic. Therefore, the candidate has the potential to replace it.

Integrated computer-aided molecular and process design: Green solvents for the hydroformylation of long-chain olefines

“…In an attempt to replace the developmentally toxic solvent DMF by a 65 safer and ecologically more benign alternative, a screening method was employed in a prior study, and promising alternatives for DMF were identified (McBride et al, 2018). In a further study by the authors, process optimization for those alternatives was conducted, and one of them delivered promis-ing results (Keßler et al, 2019). The proposed screening method was refined, and additional solvent candidates were identified by Linke et al (2020).…”

“…Owing to the size of BiPhePhos, the phase behavior with respect to the catalyst cannot be modeled using UNIFAC. However, the catalyst distri-150 bution plays an important role for the process efficiency (Keßler et al, 2019).…”

“…The process optimization is conducted like described in (Keßler et al, 2019), with some small deviations: The partition coefficient P xy of the catalyst with respect to the solvent candidates is calculated using the σ-profiles from the aforementioned group-contribution method. COSMO-SAC is used to calculate the phase behavior of the whole mixture, instead of COSMO-RS 255 (Klamt, 2005) for the catalyst distribution in combination with UNIFAC for the remaining species.…”

“…COSMO-SAC is used to calculate the phase behavior of the whole mixture, instead of COSMO-RS 255 (Klamt, 2005) for the catalyst distribution in combination with UNIFAC for the remaining species. Furthermore, as in (Keßler et al, 2019), the total costs of the distillation column are modeled using a surrogate. It is based on the conservative assumption that some decene and dodecane is recycled through the distillate stream.…”

Surrogate Modeling for Liquid–Liquid Equilibria Using a Parameterization of the Binodal Curve

“…The sizing of the column utilizes the Fenske-Underwood-Gilliland correlations [20][21][22][23] with mean mixture and component properties. A simplified cost function is generated by fitting a polynomial function to data obtained by evaluating the cost calculation for a set of different compositions of the column feed and different values of the distillate flow rate at a distillate purity of 99 % (see [24] for more details). The overall cost J in $ year −1 for this process reads…”