There’s a lot to consider when you’re looking at different types of filters, and glass fiber filters are no different. Glass fiber filters have excellent features that set them apart from other styles of filters, such as the binder and binder-free options, and the fact that they are extremely absorbent. But there’s more to it than that.
What to Know About Glass Fiber
Glass microfiber filters are actually available in two different versions. The first is the binder glass microfiber. This helps to increase the overall strength and capacity of the filter itself while also lowering what’s considered the ‘slough’ or loss of fibers. The binder itself is made with acrylic.
Of course, that means that the other option is a binder-free glass microfiber. That means you can choose to get the added capabilities or not. Either way these glass fiber filters are made with 100% borosilicate glass, which allows them to work perfectly for both filtration and the retention of particles that are even sub-micron in size.
Where to Use Glass Fiber Filters
In general, glass fiber filters are best for things like removing sediment or getting rid of more coarse materials. It offers a high flow rate, which makes it ideal to use in single and multi-process stages of this type of remediation.
They can also be used for other analytical applications. They are often used for collecting suspended solids, contamination analysis, and liquid clarification. In general, however, these are designed to be used as a pre-filter rather than as a solo filter for most applications.
Benefits of Glass Fiber Filters
There are a number of additional benefits when it comes to using glass fiber filters. These include:
- High absorbency
- Fine capillary structure
- Ideal for:
- Scintillation counting
- Spot tests
- Microscopic examination
- Thermal/chemical resistance
- Hydrophilic
- High-dirt loading capacity
- Organic solvent and acid compatibility
- Can be made transparent
- Improved wet strength
- Safe/effective up to 500 degrees centigrade
- Fast flow rate
Highly absorbent
This particular filter is able to absorb a great deal of liquid, which is crucial for its use in moisture testing including for liquids or even for pastry products.
Fine structure of capillaries
The capillaries of the filters are available in a range of different pore sizes to ensure proper filtration of different types of materials.
Thermal/chemical resistance
This filter can be used with warm applications as well as biopharmaceutical applications without losing structural integrity or compromising the material.
Hydrophilic
These filters are required to be wet to work properly and are easily wetted by water.
High-dirt loading capacity
Glass fiber filters hold a high level of contaminant prior to achieving delta P level.
Organic solvent and acid compatibility
Glass fiber filters are able to be used even with acids and organic solvents without breaking down or compromising sample or filtration integrity.
Improved wet strength
When utilized with a binder the filter decreases the risk of fiber shedding while increasing the overall strength of the filter when wet.
Come entirely transparent with use
Complete transparency allows for even more clarity of filtration and a better view of the materials utilized.
Safe to 500 degrees centigrade
Can be used even with hot materials without losing structural integrity.
Fast flow rate
Allows for both single and multi-process sediment and coarse particulate removal is possible with the high flow rate. There are a variety of flow rates available however for different uses with this filter.
Glass Fiber Syringe Filters vs. Membrane Filters
Syringe filters offer high quality and durability while also keeping the costs lower than with a membrane filter. These are designed to provide different materials and different diameters and can be used for microfiltration. Glass fiber syringe filters can come in both sterile and non-sterile and offer options in environmental, biotech, agriculture, and food and beverage.
Within these filters, the proper filter paper is essential with different varieties of pore size as well as sterile and non-sterile. Packs of filter paper are available in different options from 21 mm to 150mm and are also available in some inch sizes as well.
Membrane filters can be more expensive, which is why glass fiber membrane roll stock can be a benefit. This product offers a discount over standard membrane filters and reduces the overall waste of the product. It’s custom designed to get exactly what’s needed or it’s available in different base sizes.
Selecting the Proper Filter Characteristics
When it comes to selecting a filter for any task there is a prescribed process involved which requires four simple steps. These steps can be done with a filter media selector and include:
- Deciding on the necessity of prefiltration for the application.
- Choosing a membrane filtration material based on qualities such as aqueous, non-polar, and protein.
- Selecting a diameter typically of <10ml, <100ml, or <250ml to determine the mm diameter of the filter.
- Ensuring the pore size, based on micron size of the column of >3um or <3um.
Be sure that you evaluate the chemical compatibility guide to determine materials that glass fiber is considered compatible with. The compatibility chart will help you to evaluate ways in which the filter can be used.
Glass fiber filters are considered fully compatible or offer limited compatibility with most chemicals and halogenated hydrocarbons, ketones, and other miscellaneous materials. However, there are many assorted materials that are not compatible with this type of filter.
Some examples of non-compatible materials include hydrogen peroxide, 30%; aniline; triethanolamine; ethyl ether; many esters; phosphoric, 25%; trichloroacetic, 10%; and others. There are also some materials that are considered either incompatible or that have no data available on them.
Evaluate the material that you are looking to filter with the membrane filter version of these glass fiber filters to determine whether the filter is rated and compatible with the proper ingredients. For more information on selecting the right filtration media for your needs, watch this short video.
Types of Glass Fiber Filter Papers
Glass fiber filter papers are available in a range of different types and classifications. In general, they can be found in Grade A, Grade B, Grade C, Grade D, and Grade F, which each provide different capabilities and quality in regards to filtration.
Grade A
This grade level is the most common and offers medium retention as well as flow rate. It has particle retention of approximately 11um and nominal thickness of 180um.
Grade B
This grade level has a higher level of retention than the previous, increasing filtration time. It has particle retention of 8um and nominal thickness of 190um.
Grade C
This grade level is actually twice as thick as Grade A, increasing wet strength and the amount of material it is able to contain. It has particle retention of 6um and nominal thickness of 390um.
Grade D
This grade level is actually designed for coarse particles and even gelatinous materials, offering fast filtration. It has a particle retention of 25um and nominal thickness of 210.
Grade F
Finally, we have this grade level which offers the best in fine particle retention and has a slower flow rate. It has particle retention of 2.5um and nominal thickness of 200um.
Grades of filter papers are also available with or without binders to ensure the right balance of feature and capability of each product.
Glass Fiber Filters For Any Use
If you’re looking for filtration products for removing sediment and coarse particulate and also for high flow rate overall, glass fiber filters are an excellent option that can take care of all of this and a great deal more. The filters are ideal for tensile strength and compatibility with ultra-high temperature materials.