Biogas upgrading is one piece in the framework of future energy supply. Commonly absorption and adsorption technology is applied for biogas upgrading where CO 2 , H 2 S, and water vapor have to be removed from CH 4 . Gas permeation technology offers an interesting alternative to conventional upgrading techniques. Combining gas permeation membranes and conventional separation equipment in membrane hybrid processes merges the advantages of both technologies. Hence, we analyze seven different membrane hybrid processes for biogas upgrading. A single gas permeation stage is combined with pressurized water scrubbing, amine absorption, cryogenic separation, and a particular process in which the permeate of the gas permeation stage drives a gas engine. Furthermore, we compare the specific upgrading costs to an individual three stage membrane process as well as to conventional separation processes. Simulation studies were performed in Aspen Plus to rigorously model the different hybrid process configurations. A full cost model determines operational and investment costs. The processes combining membranes and pressurized water scrubbing outperform the conventional pressurzied water scrubbing process in terms of specific upgrading costs. The application of a membrane remarkably reduces the upgrading costs for cryogenic separation. While the conventional process is far from being profitable, the hybrid process can compete with established biogas upgrading techniques. The three stage gas permeation process and both hybrid processes involving the pressurized water scrubbing technology have the lowest upgrading costs. Ultimately, it is important to note, that the results obtained in this study rely on the parameters set here. A site were heat is provided inexpensively and low grid injection pressures are required might favor the application of amine absorption processes.

A flow process for direct amination of a pharmaceutically relevant substrate using a Pd-NHC based catalyst was demonstrated in a lab-scale mini-plant and in a pilot-scale plant.

A continuous Buchwald−Hartwig reaction using the bulky N-heterocyclic carbene (NHC) precatalyst [Pd(IPr*)(cin)Cl] 4 has been developed for the synthesis of a key pharmaceutical intermediate 2. Using microreactor technology, the reaction could be optimized under dilute conditions with low material burden and the kinetic parameters investigated. For larger lab-scale operation (gram scale), process-relevant concentrations could be employed and the conditions developed for continuous workup effectively demonstrated (batch methodology published concurrently). The stability of the NHC catalyst allowed for a continuous acidic extraction of the product and on-stream recycling of the catalyst in the organic phase. At this scale, sonication is employed to prevent clogging in the reactor unit. Finally, a bespoke continuous flow reactor has been developed for carrying out the reaction beyond lab scale. This novel reactor concept for running heterogeneous reactions in flow combines the flexibility of continuously stirred tank reactors (CSTRs) with the smooth operation, low residence time distribution and excellent heat transfer capability of a conventional flow reactor. A LCA (life cycle analysis) study has been carried out on the resulting process in comparison with the existing batch protocol, revealing it to be favorable under the majority of environmental factors considered.

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