Denise Ott

Conversion of carbohydrates into 5-hydroxymethylfurfural in highly concentrated low melting mixtures

Highly concentrated melt systems consisting of choline chloride (ChCl) and up to 50 wt% of carbohydrates, corresponding to carbohydrate concentrations of 2.9 to 3.1 mol/L, have been used for the conversion of the carbohydrate content into 5-hydroxymethylfurfural (HMF) in the presence of catalysts. Apart from the monosaccharides D-fructose and D-glucose, the disaccharide sucrose and the polyfructan inulin were successfully converted into HMF. The reported conditions with short reaction times at high concentrations may allow for high space-time yields, which may be of interest for the development of efficient continuous processes for the conversion of carbohydrates into HMF. In a preliminary ecological evaluation, the ChCl/D-fructose system is compared to other representative solvents for the synthesis of 5-hydroxymethylfurfural. The melts have an inherent low toxicological impact due to their negligible vapour pressure.

Rules and benefits of Life Cycle Assessment in green chemical process and synthesis design: a tutorial review

The implementation of Life Cycle Assessment and related methods in green chemical process and synthesis design strongly supports the development of greener concepts on the basis of deep and profound insights into the dependences between the selection of compounds and process parameters and the resulting environmental impacts. This review article provides an overview on things to know about LCA in general, specifics to be considered during its application in the field of chemical (re-)designs and current application examples from emerging research areas such as active pharmaceutical ingredient manufacturing, nanotechnology, flow chemistry, process intensification under harsh synthesis conditions, process integration, waste treatment, the use of alternative energy sources or solvents as well as chemistry based on renewable resources.

Process design accompanying life cycle management and risk analysis as a decision support tool for sustainable biodiesel production

The search for sustainable synthesis pathways for biodiesel generation is still ongoing, although extensive research and development work on this topic has already led to a broad variety of process alternatives, utilizing different feedstocks, alcohols, catalysts and process parameters. Thus, the choice for the most sustainable option is not an easy task, depending on related costs and environmental impacts deriving from up-stream and down-stream processes, but also on safety constraints. The aim of our work presented herein is to demonstrate a decision support procedure for the best suited process design of biodiesel production in front of a pilot plant construction. The development of a novel biodiesel production alternative was accompanied by Life Cycle Management and Risk Analysis in an iterative procedure nearly from the beginning in order to point out favorable process parameter combinations in parallel to experimental optimization. The transesterification of waste oil via supercritical processing in intensifying continuous flow reactors, using the feedstock methanol, was found to be the most favourable option.

Life cycle analysis within pharmaceutical process optimization and intensification: case study of active pharmaceutical ingredient production.

As the demand for new drugs is rising, the pharmaceutical industry faces the quest of shortening development time, and thus, reducing the time to market. Environmental aspects typically still play a minor role within the early phase of process development. Nevertheless, it is highly promising to rethink, redesign, and optimize process strategies as early as possible in active pharmaceutical ingredient (API) process development, rather than later at the stage of already established processes. The study presented herein deals with a holistic life-cycle-based process optimization and intensification of a pharmaceutical production process targeting a low-volume, high-value API. Striving for process intensification by transfer from batch to continuous processing, as well as an alternative catalytic system, different process options are evaluated with regard to their environmental impact to identify bottlenecks and improvement potentials for further process development activities.

Green catalysis by nanoparticulate catalysts developed for flow processing? Case study of glucose hydrogenation

Heterogeneous catalysis, flow chemistry, continuous processing, green solvents, catalyst immobilization and recycling are some of the most relevant, emerging key technologies to achieve green synthesis. However, a quantification of potential effects on a case to case level is required to provide a profound answer, whether they can lead to a superior process compared to the industrial standard. To do so, holistic environmental assessment approaches are very useful tools providing insights and decision support during the process development phase. Herein, novel heterogeneous nanoparticulate ruthenium catalysts immobilized on hyperbranched polystyrene (HPS) and nitrogen-doped carbon nanotubes (NCNT) were investigated with respect to their potential environmental impacts and improvements if utilized in an industrially highly relevant process, namely glucose hydrogenation to sorbitol. The results of a comparative Life Cycle Assessment of the alternative catalytic systems under consideration of RANEY® nickel as benchmark catalyst revealed that in particular Ru nanoparticles on porous HPS beads processed under flow-chemistry conditions have the potential to improve the greenness of the overall synthesis, but the concentration of glucose in the reaction mixture is in fact the most influential parameter.

Bridging sustainability and intensified flow processing within process design for sustainable future factories

Abstract A holistic, life cycle based evaluation approach was followed within the European collaborative project CoPIRIDE, in order to provide multi-criteria decision support for environmentally benign and cost efficient process design strategies in front of a scale-up of newly developed concepts. The approach is presented by means of three case studies, dealing on the one hand with different catalyst plate reuse options, and on the other hand with two process concepts for intensified processing of natural feedstocks by means of epoxidation and transesterification reactions. Key criteria for future sustainable production processes could be identified prior to the transfer of the experimental flow chemistry results to pilot scale processing.