Stirred Cell Membrane System for Flat-Sheet Membrane Testing and Process Development

Crossflow Membrane Filtration with the HEXAMEM Stirred Cell

HexaMem stirred cell membrane filtration system

One platform for membrane selection, fouling analysis, cleaning optimization and membrane process development.

The HexaMem stirred-cell membrane system is a laboratory membrane filtration system for membrane screening, membrane process development and flat-sheet membrane testing. It enables highly reproducible experiments with Microfiltration (MF), Ultrafiltration (UF), Nanofiltration (NF) and Reverse Osmosis (RO) membranes using only 500 mL of sample, making it ideal for the food, biotechnology and chemical industries. Researchers and process engineers can evaluate membrane flux, retention, fouling, cleaning and separation performance under controlled hydrodynamic conditions before pilot-scale or industrial process development.

Hexamem Iso

1 = Stepper Motor
2 = Magnetic Disc Drive
3 = Hexamem Body
4 = Stirrer
5 = Membrane
6 = Hexamem Permeate Body

A programmable stepper motor drives a magnetically coupled rotor to create controlled crossflow conditions directly above the membrane.

Applications

  • Membrane screening

    • Evaluate microfiltration, ultrafiltration, nanofiltration and reverse osmosis membranes under identical laboratory conditions. HexaMem enables rapid membrane screening for membrane process development, membrane selection and process optimization.

  • Flux and retention testing

    • Measure membrane flux, permeate productivity and solute retention with high reproducibility. The stirred-cell membrane system generates reliable filtration data for membrane comparison, process design and scale-up.

  • Protein concentration

    • Develop efficient ultrafiltration processes for concentrating proteins, enzymes and other valuable biomolecules. Optimize operating conditions while maximizing product recovery and minimizing membrane fouling.

  • Fermentation broth clarification

    • Investigate membrane filtration of fermentation broths before downstream purification. Evaluate membrane performance, permeate quality and filtration behavior using only small laboratory sample volumes.

  • Enzyme membrane reactors

    • Study enzyme membrane reactor processes by retaining enzymes while continuously removing reaction products through the membrane. HexaMem supports research on biocatalysis, enzyme recycling and continuous membrane reactor operation.

  • Membrane fouling studies

    • Analyze membrane fouling mechanisms under controlled pressure, stirring speed and operating conditions. Compare membranes, feed streams and operating parameters to improve long-term membrane performance.

  • Cleaning optimization

    • Develop and validate membrane cleaning procedures using realistic laboratory filtration experiments. Compare cleaning chemicals, temperatures and operating conditions to restore membrane permeability efficiently.

  • Process feasibility studies

    • Determine whether membrane filtration is technically and economically suitable for a specific separation task. Generate engineering data that supports process selection before pilot-scale investment.

  • Scale-up investigations

    • Generate laboratory data that supports membrane process scale-up and industrial equipment design. Understand process limitations, operating windows and critical parameters before pilot plant construction.

  • Process development

    • Use HexaMem to develop robust membrane filtration processes for the food, biotechnology and chemical industries. The system produces engineering knowledge required for process optimization, industrial scale-up and successful commercial implementation.

HexaMem Stirred-Cell Membrane System – Technical Datasheet (PDF)
Complete specifications, operating principles, membrane compatibility and laboratory applications. Tube-in-Tube Cooler and Heater – Technical Datasheet (PDF)
Temperature control accessory for membrane filtration, enzyme membrane reactors and process development. Pressure Vessel Dosing System – Technical Datasheet (PDF)
Pressurized feed vessel for controlled dosing, concentration experiments and membrane filtration studies.
HexaMem stirred-cell membrane system with independent magnetic stirring
Controlled shear at the membrane surface in the HexaMem stirred-cell membrane system

Controlled Shear

Reproducible hydrodynamic conditions for reliable membrane experiments.

“How does shear influence membrane performance and fouling?”

The HexaMem hexagonal chamber suppresses liquid co-rotation and promotes controlled mixing directly above the membrane surface. A magnetically driven rotor produces reproducible shear conditions for membrane screening, flux measurements, retention studies and fouling experiments.

Rotor geometry, stirring speed and acceleration profiles can be adapted to product viscosity, rheological behavior and shear sensitivity. This allows process engineers to investigate hydrodynamic effects and generate reliable engineering data for membrane process development and industrial scale-up.

  • ✓ Controlled shear at the membrane surface
  • ✓ Independent stirring speed and acceleration profiles
  • ✓ Adaptable rotor designs for different products
  • ✓ Reproducible hydrodynamic conditions for membrane research
  • ✓ Engineering data for process optimization and scale-up
Parallel membrane testing with the HexaMem stirred-cell membrane system

Parallel Membrane Testing

Compare multiple membranes in a single experiment.

“Which membrane delivers the best overall process performance?”

HexaMem allows multiple flat-sheet membranes to be tested simultaneously under identical operating conditions. Compare membrane flux, solute retention, fouling behavior and cleaning performance while eliminating variations between separate laboratory experiments.

Each stirred cell can be operated with an independent stirring speed, enabling controlled hydrodynamic conditions and investigation of shear effects on membrane performance. Automated operation generates reproducible engineering data for membrane selection, process optimization and industrial scale-up.

  • ✓ Compare multiple membranes in one experiment
  • ✓ Independent stirring speed for every membrane cell
  • ✓ Evaluate flux, retention, fouling and cleaning simultaneously
  • ✓ Eliminate experimental variation between separate tests
  • ✓ Generate reproducible engineering data for process development and scale-up
Small-volume membrane filtration with valuable sample material

Small-Batch Processing

Generate membrane process data without wasting valuable product.

“I cannot afford to waste this material.”

HexaMem is designed for laboratory membrane testing with limited, rare or expensive samples. It enables membrane screening, flux testing, retention studies and sample generation using only small feed volumes.

Obtain permeate and retentate samples while conserving valuable product for further analysis, formulation work and membrane process development.

  • ✓ Product concentration
  • ✓ Purification and fractionation
  • ✓ Process feasibility studies
  • ✓ Sample generation for analytical testing
  • ✓ Scale-up relevant data acquisition
Membrane cleaning and CIP optimization with HexaMem stirred-cell membrane system

CIP – Cleaning Optimization

Develop the most effective membrane cleaning protocol.

“Which cleaning procedure restores membrane performance most effectively?”

HexaMem enables reproducible membrane fouling and controlled cleaning studies using multiple flat-sheet membranes in parallel. Cleaning performance is quantified through permeability and flux recovery measurements before and after each cleaning cycle.

Compare cleaning chemicals, concentrations, temperatures and Cleaning-In-Place (CIP) procedures side by side to identify the most efficient cleaning strategy while minimizing downtime and chemical consumption.

  • ✓ Compare multiple cleaning protocols in one experiment
  • ✓ Quantify permeability and flux recovery
  • ✓ Evaluate cleaning chemicals, concentrations and temperatures
  • ✓ Investigate reversible and irreversible membrane fouling
  • ✓ Optimize Cleaning-In-Place (CIP) procedures before scale-up
Enzyme membrane reactor for reaction and membrane separation using the HexaMem stirred-cell membrane system

Enzyme Membrane Reactors

Combine enzymatic reaction and membrane separation in a single process.

“How can I increase conversion while continuously recovering the product?”

HexaMem enables laboratory-scale investigation of enzyme membrane reactors (EMRs), where enzymatic conversion and membrane separation occur simultaneously. The system allows process engineers to evaluate enzyme retention, substrate conversion, product recovery and membrane performance under well-controlled operating conditions.

By retaining enzymes while continuously removing reaction products, HexaMem supports the development of efficient biocatalytic membrane processes with minimal sample consumption. The resulting engineering data provide the foundation for process optimization and industrial scale-up.

  • ✓ Protein hydrolysis and peptide production
  • ✓ Lactose hydrolysis and bioconversion processes
  • ✓ Enzyme retention and continuous product removal
  • ✓ Biocatalytic membrane process development
  • ✓ Engineering data for membrane reactor scale-up

Frequently Asked Questions

A stirred-cell membrane system is a compact laboratory filtration device used to test flat-sheet membranes under controlled pressure and mixing conditions. It is typically used for membrane screening, flux measurements, retention studies, fouling tests and early process development.

In dead-end filtration, the feed flows directly toward the membrane and particles accumulate on the membrane surface. In crossflow filtration, the feed flows tangentially across the membrane, which reduces cake formation and improves process stability. A stirred cell creates controlled shear at the membrane surface and can simulate important aspects of crossflow behavior on a small laboratory scale.

HexaMem is designed for small-volume laboratory work. Typical experiments can be performed with sample volumes in the range of a few hundred milliliters up to approximately one liter, depending on the test setup, membrane area, concentration factor and required analytical samples.

HexaMem can be used to test flat-sheet membranes for microfiltration, ultrafiltration, nanofiltration and reverse osmosis applications. This makes it suitable for early membrane selection, retention testing, flux comparison and process feasibility studies.

Yes. Ceramic flat-sheet membranes can be tested if they match the required geometry and sealing concept. Ceramic membranes are useful for demanding applications involving aggressive cleaning, high temperature stability or challenging feeds.

Yes. Polymer flat-sheet membranes such as PES, PVDF, PP, PAN or other membrane materials can be used, provided they are chemically compatible with the feed, cleaning agents, temperature and operating pressure.

The possible operating pressure depends on the specific configuration, membrane, seals and accessories. HexaMem can be configured for pressure-driven membrane experiments such as ultrafiltration, nanofiltration and reverse osmosis screening. The final pressure rating should always be confirmed for the selected setup.

Yes. HexaMem is suitable for fouling studies, cleaning tests and flux-decline experiments. By controlling pressure, stirring speed, time and sample composition, membrane fouling behavior can be investigated under reproducible laboratory conditions.

Yes. HexaMem can be used for enzyme membrane reactor studies, for example when enzymes or biocatalysts are retained by the membrane while reaction products pass into the permeate. This allows small-scale investigation of reaction, separation and retention behavior in one system.

HexaMem is designed as an engineering-oriented stirred-cell membrane system. Compared with conventional stirred cells, it focuses not only on simple membrane screening, but also on reproducible process experiments, defined hydrodynamic conditions, flexible operation modes and the generation of scale-up relevant membrane process data.