Polymeric Membrane MorphologyMicroza* ultrafiltration membranes are unique in their construction. Every membrane has an asymmetric structure,with a membrane layer both on the inside, and on the outside of the fiber, overlaying a core comprising a very open support for excellent flow characteristics, and a central strengthening layer for outstanding fiber durability in long-term service. Microza ultrafiltration membranes are resistant to flow in both directions, so there is no risk of delamination or membrane rupture during accidental back-pressure. In fact, in many installations, backpulsing can be used to maintain flux during extended run times.
Microza micofiltration membranes have smooth inner and outer membrane skins with a highly porous symmetrical support structure giving high-flow rates. These modules can also be backflushed.
All Microza membranes have surfaces that minimize entrapment and facilitate cleaning. All Microza membranes are manufactured in a single step, and are not composed of laminates. Membranes and modules are subjected to rigorous quality control to ensure consistency of performance, durability in service, and module integrity for the most demanding applications.
Polyolefin (P)Polyolefin membranes are a good choice for bulk clarification processes where sterility is not essential. Nevertheless, P-membranes have good retention characteristics coupled with high flux rates. Availability in fine microfiltration retention ratings ensures protection of downstream processing equipment. .
The P series of Microza hollow fiber microfiltration modules feature unique proprietary membranes in polyolefin for general microfiltration applications. Available in 0.1 µm rating, the modules are used in a range of pharmaceutical applications especially in clarification of microbial cultures for enzyme production, clarification of natural product extracts, and nutraceutical production.
- Available different internal fiber diameters provides suitability for processes with varying particulate or colloidal loading
- Broad chemical resistance ensures compatibility in a wide range of processing and cleaning conditions
- Highly characterized,optimized void structure ensures reproducible separation efficiency and high throughput
- High-strength fiber allows reverse filtration to optimize yield and performance in difficult applications
- Available in a range of sizes from 0.09 m2 (1 ft2) to over 8 m2 (85 ft2)
- P series compatible for continuous operation up to 50 °C
- Meets the specification for biological tests listed in the current revision of USP for Class VI plastics at 121 °C
Microza Module TypesMicroza hollow fiber modules are available with housings made from polysulfone (native, clear), filled polysulfone (white, opaque), and polyvinylchloride (PVC). Polysulfone modules will withstand autoclaving and in some cases steaming. Clear polysulfone modules are recommended for more critical pharmaceutical applications. Filled polysulfone and PVC modules are ideally suited to long term installations where light might cause biofilm to form, or for bulk processes involving light sensitive materials. PVC modules are idea for use in feed water systems and bulk processes.
Microza modules are available with industry standard clamp fittings on the feed and retentate side, and some with quick connects. All steamable modules designed for long term use in critical applications such as perfusion have sanitary clamp connections on the feed/retentate and filtrate sides, or filtrate hose barbs on laboratory scale modules.
Retrofitting Existing ApplicationsTo retrofit an existing application,membrane rating should be chosen to be equivalent or superior in performance. For ultrafiltration membranes, this may require testing more than a single cut-off. Differences in membrane area and lumen diameter can typically be accommodated by adjustments to operating conditions to ensure that trans-membrane pressure and fluid velocity conditions at the membrane surface are similar. Hollow fiber modules can be joined end-to-end as required to create similar path length systems. Small adjustments to physical dimensions, and differences in connection type are accomplished using adapters. Please contact Pall for assistance with selecting the right modules to retrofit an existing installation.
* Microza is a trademark of Asahi Kasei Corporation
Materials of Construction
|Housing||Native clear polysulfone (P) or PVC (V)|
|Potting Material||Epoxy Resin|
|Bacteriostat||Glycerin 65%, Ethanol 2%, water balance|
Connectors and Adapters
|A - A1||Small hose barb 4.5 mm (3/16 in.)|
|A2||Small hose barb 6 mm (¼ in)|
|B - B1||
Quick connect -To convert feed/retentate to:
|C - C3||1 in. sanitary flange (ferrule face 34 mm [1.34 in.])|
|C4||1½ in. sanitary flange (ferrule face 50 mm [1.98 in.])|
|C5||2 in. sanitary flange (ferrule face 64 mm [2.52 in.])|
|C7||4 in. sanitary flange (ferrule face 117 mm [4.61 in.])|
|C8||6 in. sanitary flange (ferrule face 157 mm [6.18 in.])|
|D - D2||Cap nut, 38.5 mm diameter|
|D3||Cap nut, 48.5 mm diameter|
Part Numbers and Technical Specification - Table 1 1
|Fiber ID||Nominal Length (2)
|Clean Water Flux
|Crossflow Rate for 1ms-1 fluid velocity|
Part Numbers and Technical Specification - Table 2 1
|Part Number||Maximum Pressure (barg) Feed/TMP/Permeate at 50 oC||Volume Feed Side (3) (mL)||Volume Permeate Side (3) (mL)||Feed/Retentate Connection||Permeate Connection|
(2) Nominal length is flange to flange, or to ends of connectors on quick-connect modules. Detailed drawings available upon request.
(3) Guideline module filling volume to allow calculation of minimum system working volumes when added to volumes of attached piping and other components. Draining residual volumes are considerably less.