Membranes
Membranes enable a very convenient, fast and economical separation.
Often they are also used as a neutral sample support for further analysis.
| Overview of available membrane filters | ||
| Material | Properties and pore sizes | Type |
| Cellulose mixed esters | – suitable for aqueous solutions – also available sterile and/or with grid – recommended for gravimetric analysis – autoclaving possible at 121 °C – economical – pore sizes 0.2 – 0.45 µm |
PORAFIL® CM |
| Cellulose mixed esters, fabric-reinforced |
– suitable for aqueous solutions – higher mechanical stability than PORAFIL® CM – pore sizes 0.2 – 0.45 – 0.8 |
PORAFIL® MV |
| Cellulose nitrate | – thermally stable up to 125 °C – autoclaving possible at 121 °C – pore sizes 0.2 – 0.45 µm |
PORAFIL® NC |
| Polycarbonate | – very low halogen blank values – suitable for quantitative AOX determination – thermally stable up to 140 °C – pore sizes 0.4 µm |
PORAFIL® PC |
| Cellulose acetate | – suitable for aqueous and many alcoholic media – low protein binding capacity – thermally stable up to 180 °C – pore sizes 0.2 – 0.45 – 0.8 – 1.2 µm |
PORAFIL® CA |
| Polytetrafluoroethylen (PTFE) | – hydrophobic membrane – suitable for almost all solvents, chemical resistance towards acids and bases – for filtration of aggressive media – thermally stable up to 145 °C – pore sizes 0.2 – 0.45 – 1.0 – 3.0 µm |
PORAFIL® TE |
| Polyester | – chemically very resistant membrane ( not as stable as PFTE) – suitable for TOC/DOC determination – thermally stable up to 150 °C – pore sizes 0.2 – 0.4 – 1.0 – 5.0 µm |
PORAFIL® PE |
| Regenerated cellulose | – suitable for all media except strong acids and bases – thermally stable up to 180 °C – pore sizes 0.2 – 0.45 µm |
PORAFIL® RC |
