title: Agile green process design for the intensified Kolbe-Schmitt synthesis by accompanying (simplified) life cycle assessment.
abstract: In order to investigate the potential for process intensification, various reaction conditions were applied to the Kolbe-Schmitt synthesis starting from resorcinol. Different CO₂ precursors such as aqueous potassium hydrogencarbonate, hydrogencarbonate-based ionic liquids, DIMCARB, or sc-CO₂, the application of microwave irradiation for fast volumetric heating of the reaction mixture, and the effect of harsh reaction conditions were investigated. The experiments, carried out in conventional batch-wise as well as in continuously operated microstructured reactors, aimed at the development of an environmentally benign process for the preparation of 2,4-dihydroxybenzoic acid. To provide decision support toward a green process design, a research-accompanying simplified life cycle assessment (SLCA) was performed throughout the whole investigation. Following this approach, it was found that convective heating methods such as oil bath or electrical heating were more beneficial than the application of microwave irradiation. Furthermore, the consideration of workup procedures was crucial for a holistic view on the environmental burdens.
authors.affiliation: Institute of Technical Chemistry and Environmental Chemistry, Friedrich-Schiller-University Jena, Lessingstr. 12, D-07743 Jena.
authors.forename: Sabine
authors.initials: S
authors.lastname: Kressirer
authors.forename: Dana
authors.initials: D
authors.lastname: Kralisch
authors.forename: Annegret
authors.initials: A
authors.lastname: Stark
authors.forename: Ulrich
authors.initials: U
authors.lastname: Krtschil
authors.forename: Volker
authors.initials: V
authors.lastname: Hessel
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry*
chemical_list: D052578:Ionic Liquids; D002245:Carbon Dioxide