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Ultrafiltration with ceramic hollow fiber membranes was investigated by compressed sensing rapid acquisition relaxation enhancement (CS‐RARE) magnetic resonance imaging (MRI) to characterize filtration mechanisms. Sodium alginate was used as a model substance for extracellular polymeric substances. Dependent on the concentration of divalent ions like Ca2+ in an aqueous alginate solution, the characteristics of the filtration change from concentration polarization to a gel layer. The fouling inside the membrane lumen could be measured by MRI with a CS‐RARE pulse sequence. Contrast agents have been used to get an appropriate contrast between deposit and feed. The lumen was analyzed quantitatively by exploring the membrane's radial symmetry, and the resulting intensity could be modeled. Thus, different fouling mechanisms could be distinguished. CS‐RARE‐MRI was proven to be an appropriate in situ tool to quantitatively characterize the deposit formation during in‐out filtration processes. The results were underlined by flux interruption experiments and length dependent studies, which make it possible to differentiate between gel layer or cake filtration and concentration polarization filtration processes. © 2018 American Institute of Chemical Engineers AIChE J, 64: 4039–4046, 2018 [ABSTRACT FROM AUTHOR]

One essential process step during electrode processing for lithium-ion batteries is the drying of the wet particulate electrode coating. The electrode film solidifies during evaporation of the solvent and a porous film is formed. In this study, we focus on the influence of drying temperature on the internal electrode structure of the dry film. Anode slurries that consist of graphite and an aqueous binder system were coated and subsequently dried. To assure defined and controllable drying conditions, a laboratory set-up with a temperature-controlled substrate carrier and an impingement dryer was used. To facilitate a scale-up to continuously passed dryers, the choice of experimental temperatures was based on a calculation of steady-state temperatures that result from gas temperatures that are commonly applied in industrial drying processes. The delamination behavior of the differently dried electrodes was investigated by means of a 90° peel test. The results show a strong dependency of electrode adhesion on drying temperature. A lower adhesion force at higher temperatures hints at a variation in binder content at the interface between the copper substrate and the coating layer. The formation of a consolidation layer at the air-film interface during drying is identified as a possible explanation and a criterion for consolidation layer formation is suggested. [ABSTRACT FROM PUBLISHER]