PES Membrane Filter Cartridge – Standard & Plus

Product description

Hydrophilic PES membrane filter cartridge for sterile liquid filtration

The PES membrane filter cartridge is designed for high-purity liquid filtration applications where absolute particle retention, high flow rates and excellent chemical compatibility are required. Manufactured using a naturally hydrophilic polyethersulfone (PES) membrane, the cartridge provides consistent and predictable filtration performance without the need for pre-wetting.

Thanks to the highly asymmetric pore structure of the PES membrane, the cartridge delivers high flux rates while maintaining low pressure drop. The all-polypropylene construction ensures low extractables and compatibility with a wide range of process fluids.

This product range is available in two membrane constructions, allowing the cartridge to be matched precisely to process demands:

• Standard version: single-layer PES membrane

• Plus version: double-layer PES membrane with integrated pre-filtration

Filtration principle

The PES membrane cartridge operates using hydrophilic membrane filtration.

• Process liquid flows from the outside to the inside of the cartridge

• The hydrophilic PES membrane wets easily and uniformly

• Particles, microorganisms and contaminants larger than the pore size are retained on the membrane surface

• Clean filtrate passes through to the outlet

This filtration principle provides:

• absolute rated microbial and particulate retention

• high flow rates at low differential pressure

• consistent and repeatable filtration performance

• excellent wettability without alcohol pre-wetting

Standard version – single layer PES membrane

The standard version uses a single layer of hydrophilic PES membrane and is optimised for efficient bioburden reduction in clean liquid streams.

Key characteristics

• single-layer hydrophilic PES membrane

• absolute rated microbial retention

• high flow capacity due to asymmetric membrane structure

• low protein binding

• excellent chemical compatibility

• low extractables and low TOC contribution

• suitable for steam sterilisation

This version is ideal for applications with controlled feed quality and standard service life requirements.

Plus version – double layer PES membrane

The Plus version incorporates an additional PES pre-filtration membrane layer upstream of the final membrane.

Key characteristics

• dual-layer hydrophilic PES membrane construction

• integrated pre-filtration for improved dirt holding capacity

• higher throughput and extended service life

• lower pressure increase over time

• improved protection of the final membrane layer

• enhanced resistance to frequent sterilisation cycles

This version is particularly suited to demanding processes where higher particulate loading, longer operating cycles or reduced filter change-out frequency are required.

Design and construction

Both versions are built using a pleated membrane format to maximise effective filtration area.

Typical design features include:

• hydrophilic PES membrane media

• pleated membrane construction for high surface area

• polypropylene membrane support layers

• polypropylene drainage layers

• rigid polypropylene inner core

• polypropylene outer support cage

• thermally bonded construction without adhesives, binders or surfactants

This design ensures high mechanical integrity and consistent filtration performance.

Materials of construction

• Filter membrane: Polyethersulfone (PES)

• Pre-filter membrane (Plus version): Polyethersulfone

• Support layers: Polypropylene

• Drainage layers: Polypropylene

• Inner core: Polypropylene

• Outer support cage: Polypropylene

• End fittings: Polypropylene

• Support ring: Stainless steel

• Sealing options:

  • EPDM

  • Silicone

  • Viton®

  • Nitrile

  • FEP encapsulated

Operating conditions

Typical operating conditions include:

• absolute micron ratings suitable for sterile liquid filtration

• continuous operating temperatures up to approximately 80–90 °C

• high allowable differential pressure depending on temperature

• suitability for forward and limited reverse flow operation

Exact limits depend on cartridge version, pore size, length and process conditions.

Sterilisation and integrity testing

PES membrane filter cartridges are designed for validated and critical filtration processes.

• suitable for in situ steam sterilisation

• compatible with hot water sanitisation

• supplied integrity tested during manufacture

• integrity testable using standard non-destructive methods, including:

  • diffusive flow testing

  • pressure hold testing

  • bubble point testing

Key benefits

• Naturally hydrophilic PES membrane

• Absolute rated microbial retention

• High flow rates with low pressure drop

• Low protein binding

• Broad chemical compatibility

• Low extractables and low TOC

• Available in Standard and Plus (double-layer) versions

• Suitable for critical and validated applications

Typical applications

These cartridges are commonly used in:

• pharmaceutical and biopharmaceutical processing

• biotechnology and fermentation

• food and beverage production

• beer and wine clarification

• fine chemical processing

• pure and process water systems

• ophthalmic and cosmetic solutions

Configuration options

Available configuration options include:

• Standard or Plus membrane construction

• multiple absolute micron ratings

• standard cartridge lengths

• double open end and single open end configurations

• 222 and 226 O-ring connections with or without fin

• multiple sealing material options

This ensures compatibility with standard filter housings and specific process requirements.