External Filtration System

An automated and compact instrument that removes carbon black and small-particle size fillers from the sample before an analysis.

External Filtration System

EFS Overview

Filtration is required in many cases before injection when using light scattering detectors, but also to extend the life of fragile Gel Permeation Chromatography (GPC) columns. Polymer Char, with the most complete range of instruments for Polyolefin Characterization, has introduced this year a series of accessories to facilitate this task in the polyolefin characterization laboratories; the External Filtration System (EFS) is an automated, fast and innovative apparatus for eliminating carbon black, rest of catalysts or other additives of small particle size that may be present in polyolefin samples.

The process is fast, easy, and safe for the user as there is no solvent handling nor manual vial transfer. Once the sample is dissolved, the user pierces the vial on the system and starts the EFS operation. Then, the solution is automatically transferred to an empty vial while passing through a disposable filtration cartridge. Around 2 minutes later, the sample is clean and ready to be injected into the GPC instrument.

Thanks to its smart design, the solution travels through those disposable cartridges only, so no-cross contamination may occur nor any vapors are released to the ambient as solvent circulates through a closed circuit only, unlike the manual and traditional way using glass fiber filters, or the available semi-automated equipment from other providers. After each filtration process, another one can be started right away, minimizing the user dedication to the filtration tasks, which are usually tedious and require significant manpower within the daily tasks of all the laboratories.

The EFS is a breakthrough in external filtration, being the only automated system in the market capable of eliminating the carbon black completely in an effective, fast, and safe process.

EFS Features

Facilitating Laboratory Operations

· Automated and fast filtration of carbon black, catalysts residue, or other fillers of small-particle size
· No manual handling of solvents
· Safe and clean filtration in a few minutes
· No cross-contamination
· No transfer of vials
· No vapors or odors are released to the ambient thanks to the closed circuit and closed elements, which include a vapor collecting bottle
· The vial with the filtered solution can be directly analyzed in the GPC-IR, CEF, CFC, or any other Polymer Char instrument
· Compatible with 10mL and 20mL Polymer Char vials
· An External Dissolution Oven with 6 positions is included. Dissolution time, level of shaking and temperature, from ambient up to 160ºC, are all programmable
· The maximum concentration to be filtered is 4-5mg/ml per cartridge

EFS Video


Samples with carbon black, fillers, or other pigments of small-particle size can cause significant damages to your analytical instrument and its detectors, such as:
· Damage to the chromatographic columns, especially in GPC systems (decreasing the lifespan of the columns)
· Obstructions in the system
· The In-line filter can get plugged too soon
· Noise in the signals of the Light Scattering detector
Therefore, it is highly advisable to filter those kinds of samples in order to eliminate carbon black, pigments, or any other catalyst residues for better protection and care of our instrument.

First, dissolve the sample in the External Dissolution System, (EDO). Then, place an empty vial, a new cartridge, and the vial to be filtered in the EFS cylinder, and press the Start button. A few minutes later, the clean sample will be ready in the previously empty vial.

The solution only travels from the dissolution vial, through the filter to reach the empty vial. Therefore, no part at the EFS gets in contact with the solution and the system is free of cross-contamination.

The recommended concentration is 4-5 mg/mL in 10mL or 20mL vials.

No, there is no need for transferring the solution to another vial. The resulting vial can be used for the analysis in any Polymer Char instruments. However, replacing the septum is recommended to ensure a proper closing, and also to avoid contamination.

Filters are not reusable, unless you are filtering more than one vial with the same sample. Then you may reuse them a few times, as long as the total concentration does not exceed 4-5mg/ml.

If you plan to filter more samples the same day, it is advisable to leave it on, so it is hot and ready for filtrating straight away. If you do not plan to filter more samples during the day nor in the upcoming days, there is no need for leaving it on.
The heating time of the system is between 20-30 minutes, depending on filtration temperature.

No odors or vapors are released from the system thanks to the closed circuit and disposable filters, however it is advisable to place the system inside of a fumehood for an even safer manipulation of the vials and replacement of the septum after filtration.

The filtration is usually done at 160-170ºC, a little higher than the dissolution temperature, for polyolefin samples using TCB as solvent. The temperature range of the EFS equipment is between 40ºC and 180ºC.

No differences have been noticed between the filtered sample and the original one when analyzed by GPC. The chromatograms are identical so there is no loss of the high molecular weight part of the sample, which is more sensitive during sample preparation process. Experimental tests have shown this as stated in the poster “Filtration of polymer solutions and carbon black removal prior to a GPC analysis” (ask for the document here).
Additionally, there will be no polymer retention in the filtration support as long as the sample is completely dissolved prior filtration.

Request More Information about the EFS

Thank you for your interest. If you would like to receive more information or want to request a quotation please complete this form.

* Required fields

This site uses cookies to give you a better browsing experience. If you continue browsing this site we understand that you accept our use of cookies.
For more information, please visit our Cookies Policy. You can configure which cookies you accept by ticking the next options: