Filtration is a fundamental process in laboratories across industries, from pharmaceutical development and botanical extraction to chemical manufacturing and environmental testing. The right filtration setup ensures purity, precision, and regulatory compliance.
However, not all filtration systems are created equal. If you're separating solids from liquids, clarifying extracts, or removing impurities on a molecular level, your chosen tools will directly affect your workflow efficiency and final results.
In laboratories, filtration is a physical separation process where a porous medium (like filter paper or membranes) retains solid particles or suspended material while allowing liquids or gases to pass through.
It’s used to:
Büchner funnels are rigid, vacuum-compatible funnels that hold filter paper across a perforated plate. When connected to a filter flask and vacuum pump, they create suction that rapidly draws liquid through the paper while retaining solids.
Available in glass or porcelain for most solvent applications and plastic for single-use or corrosive samples, this method is significantly faster than gravity filtration and yields cleaner, drier solids.
It’s ideal for isolating recrystallized products, harvesting botanical solids from ethanol/water extracts, and handling medium-to-large volume vacuum filtrations. Its speed and efficiency make it indispensable for crystallization and botanical extraction workflows.
Vacuum pumps are the driving force behind pressure-assisted filtration systems. They reduce atmospheric pressure in a closed vessel, pulling liquids through filter media more rapidly and efficiently than passive methods.
Common Lab Pump Types:
Best for:
Match the pump type to your desired vacuum depth, solvent compatibility, and lab noise tolerance.
Membrane filters are thin films with uniform pore structures that block particulates based on size. They’re available in disc or cartridge formats to clarify, sterilize, or prepare samples before analysis.
Pore sizes:
Materials:
Best for:
Always verify solvent compatibility with your membrane material.
Syringe filters are disposable, single-use filtration devices that attach to a syringe barrel. They allow quick filtration of small volumes (typically <100 mL) without setting up full-scale vacuum systems.
Each unit houses a membrane filter sealed in a plastic housing, and most are color-coded for material type and pore size.
Best for:
Advantages:
Match the membrane material and the housing plastic to your sample’s chemistry. For instance, PES membranes work well with protein-rich solutions, and polypropylene housings are compatible with most solvents.
Filter paper provides the physical barrier in both gravity and vacuum filtration setups. Available in varying retention levels and flow rates, it's chosen based on the particle size to be removed and the type of funnel used.
Types:
Best for:
Always select the correct diameter for your funnel and verify chemical compatibility with your sample or solvent.
Adsorbents are solid materials that capture unwanted compounds from a solution through surface interaction rather than absorption. They're essential for purification and remediation, especially when clarity, color, or chemical composition matters.
Used for: Removing pigments, waxes, fats, residual solvents, pesticides, polar compounds, and odors.
Common types include:
These media are often packed into stainless steel CRC housings or used in-line with filtration columns during processing.
Separatory funnels enable liquid-liquid extraction, where two immiscible solvents are separated based on density. They’re simple but essential tools in organic chemistry and plant extraction workflows.
Two liquids of different densities are added to the funnel. After settling, the denser layer can be drained from the bottom. Most lab-grade funnels are borosilicate glass, featuring PTFE stopcocks for chemical resistance and precise flow control.
Used for:
Centrifugal filters combine size-exclusion membranes with centrifugal force to separate, concentrate, or clean up macromolecules in solution. As the sample spins, smaller molecules pass through the membrane while larger ones are retained.
Used in:
Consider:
There’s no one-size-fits-all setup. The right filtration equipment depends on your application, materials, and processing scale:
Not sure where to start? USA Lab can help configure the proper setup based on your process, materials, and production goals.
At USA Lab, we offer a wide selection of filtration tools and supplies, from vacuum systems and Büchner funnels to high-grade adsorbents and membrane filters.
Running a small lab or managing high-throughput extraction? We have the right filtration tools for your exact needs.
Browse our filtration products or contact our team for help finding the best setup for your workflow.