Glass Nutsche filters are used for solid-liquid separation, washing, filtration, and selected reaction-plus-filtration processes where visibility and corrosion resistance are important.
HJCHEM manufactures glass Nutsche filtration systems from benchtop laboratory scale to pilot scale(500ml to 100L). Instead of offering only one standard structure, the system can be configured around the actual process, with options for vacuum filtration, agitation, jacketed temperature control, different filter media, filtrate collection, and easier wet-cake discharge.
For applications that require more than basic filtration, the equipment can also be customized as a multifunctional filter reactor for repeated washing, resin handling, crystallization, or selected solid-phase synthesis processes.
What Is a Glass Nutsche Filter?
A glass Nutsche filter is a closed filtration vessel designed for controlled solid-liquid separation, filtration, washing, and wet-cake handling.
Compared with a simple open vacuum filter, it provides better process containment and allows operators to observe slurry behavior, cake formation, washing, and liquid removal through the transparent borosilicate glass vessel.
Depending on the process, a Nutsche filter may be a simple filtration vessel or a more integrated filter reactor with agitation, a temperature-control jacket, customized ports, and solids-handling features.
The appropriate glass Nutsche filter design and configuration therefore depends on the material, filtration purpose, washing requirements, batch scale.
HJCHEM Glass Nutsche Filter Design
Below are some of our standard and customized glass Nutsche filter models for laboratory, pilot, pharmaceutical, and solid-phase synthesis applications.
HJCHEM Glass Nutsche Filter Specifications
| Specification | GFR-500ml | GFR-1L | GFR-2L | GFR-5L | GFR-10L | GFR-20L | GFR-30L | GFR-50L | GFR-100L |
|---|---|---|---|---|---|---|---|---|---|
| Nominal Capacity | 500 mL | 1 L | 2 L | 5 L | 10 L | 20 L | 30 L | 50 L | 100 L |
| Jacket Capacity | ≈30 mL | ≈200 mL | ≈200 mL | ≈1 L | ≈4 L | ≈5 L | ≈8 L | ≈10 L | ≈15 L |
| Upper / Lower Flange Diameter | 110 mm | 150 mm | 205 mm | 265 mm | 340 mm | 400 mm | 495 mm | ||
| Lid Ports | 5 customizable ports: agitator, liquid feed, temperature, vent and condenser | 6 customizable ports: agitator, liquid feed, temperature, solid feed, vent and spare port | |||||||
| Vessel-to-Lid Connection | Quick-release clamp | Flange connection | |||||||
| Speed Control / Display | — | Variable-frequency speed control with digital temperature and speed display | |||||||
| Stirring Speed | 100–600 rpm | 50–400 rpm | 0–400 rpm | 0–280 rpm | |||||
| Sealing Type | Self-lubricating stirring seal | Self-lubricating mechanical seal; magnetic coupling seal customizable | |||||||
| Agitator Type | Anchor or four-blade impeller; other designs customizable | ||||||||
| Filter Plate Material | Modified PTFE sintered filter plate; 316 stainless steel sintered mesh, PTFE filter cloth optional | ||||||||
| Filter Pore Size | 40–60 μm standard; customizable from 1–160 μm | ||||||||
| Filter Plate Diameter | — | 213 mm | 275 mm | 364 mm | 364 mm | 468 mm | |||
| Drive Type | Overhead stirrer | Geared agitator drive | |||||||
| Motor Power / Gear Ratio | 75 W | 100 W | 180 W / 1:3 | 370 W / 1:5 | |||||
| Power Supply | 220 V / 50 Hz standard; voltage and frequency customizable | ||||||||
| Certification | CE | ||||||||
Note: Specifications can be customized according to process requirements. Final configuration may vary depending on material properties, filtration conditions, and application.
How Is Filtrate Removed？
Because the vessel is made of glass, glass Nutsche filters are designed for negative-pressure vacuum filtration rather than positive-pressure filtration.
After the slurry enters the vessel, solids are retained above the bottom filter medium while the liquid phase is removed from below.
HJCHEM normally uses two filtrate-removal arrangements.
Important: Standard HJCHEM glass Nutsche filters are intended for negative-pressure filtration. The glass vessel should not be used to create positive gas pressure above the wet cake to force liquid through the filter medium. If positive-pressure filtration is required, a stainless steel Nutsche filter(10L to 1000L) is generally more appropriate.
1. Vacuum Filtration with a Filtrate Receiver
In the standard vacuum-filtration arrangement, a filtrate receiver is installed beside the glass filtration vessel.
The receiver is connected to a vacuum pump. Negative pressure on the receiver side draws the liquid through the filter medium and into the collection vessel, while the wet cake remains inside the glass vessel.
This arrangement is practical for laboratory and pilot filtration, washing, and process-development work. The separate receiver also allows the filtrate to be collected and handled independently from the retained solids.
2. Filtrate Removal with a Pneumatic Diaphragm Pump
Another option is to use a pneumatic diaphragm pump to transfer the filtrate from below the filter plate.
In this arrangement, the filtrate is pumped directly to a downstream receiving vessel or the next process stage.
This can be more convenient when the filtrate volume is relatively large, when direct filtrate transfer is preferred, or when the downstream process does not require a separate vacuum collection vessel.
How Is Wet Cake Discharged?
After filtration and washing, the remaining wet cake must be removed from the vessel.
For small laboratory batches, manual unloading is usually sufficient. However, as vessel size and cake weight increase, manual removal becomes slower and less convenient.
HJCHEM can therefore provide two additional discharge designs.
1. Liftable and Tiltable Vessel
The vessel can be designed with a liftable and tiltable structure.
After filtration is complete, the vessel can be raised and tilted so operators have easier access to the wet cake. The same structure also provides better access to the vessel and filter plate during cleaning and maintenance.
This design is particularly useful for laboratory and small pilot systems where frequent batch discharge is required.
2. Hydraulic Lifting Trolley with Material Tray
For larger or heavier batches, HJCHEM can provide a hydraulic lifting trolley together with a stainless steel material tray.
The tray is positioned below the vessel during unloading so that the wet cake can be discharged directly onto it. After discharge, the trolley can be lowered and moved away from the equipment, making material transfer to the next processing step easier.
The discharge method should therefore be selected according to vessel size, expected wet-cake quantity, product characteristics, operating frequency, and downstream material handling.
Typical Configurations of HJCHEM Glass Nutsche Filters
Full jacket design allow efficient heating and cooling, larger filtration area and faster filtration efficiency
Customized glass overheads support dosing addition, vacuum and CIP cleaning.
Bottom 3-way valve allow nitrogen purging and prevent crystal blockage of filter base plate
Liftable filter structure is more convenient for unloading resin and cleaning.
Typical Applications
Glass Nutsche filters are suitable for laboratory and pilot-scale processes that require controlled solid-liquid separation, washing, and product recovery.
Typical applications include:
- Filtration and solid-liquid separation
- Crystallization and crystal washing
- Pharmaceutical and API process development
- Fine chemical filtration
- Catalyst and solid product recovery
- Resin washing
- Solid-phase synthesis and SPPS
- Purification and solvent exchange
The transparent glass vessel is particularly useful during process development, where filtration behavior, cake formation, washing, and product condition need to be observed directly.
Need a Glass Nutsche Filter for Your Process?
The right configuration depends on more than vessel capacity.
Send HJCHEM your:
- batch size or required vessel volume;
- approximate particle size or required filtration pore size;
- slurry viscosity, if known;
- operating temperature;
- agitation requirement;
- preferred filtrate collection method;
- wet-cake discharge requirements.
Based on these process details, HJCHEM can recommend a suitable glass Nutsche filter design.
Contact HJCHEM for a technical proposal and quotation for your filtration process.
FAQ (with answers)
1. What is a glass Nutsche filter used for?
A glass Nutsche filter is mainly used for solid-liquid separation, filtration, washing, and wet-cake handling. Depending on the configuration, it can also support mixing, reaction-plus-filtration, resin washing, and selected solid-phase processes.
2. Can a glass Nutsche filter use positive pressure for filtration?
No. HJCHEM glass Nutsche filters are designed for negative-pressure vacuum filtration. If positive pressure above the filter cake is required, a stainless steel Nutsche filter is generally more appropriate.
3. Can a glass Nutsche filter be used for SPPS?
Some configurations can be adapted for resin-based synthesis workflows. For peptide applications, a customized solid phase peptide synthesis reactor is usually recommended.
4. What pore size should I choose?
Pore size should be selected according to particle size, solids-retention requirements, filtration rate, and washing conditions. A smaller pore size is not always better because an excessively fine filter medium may reduce filtration speed.
5. How is the filtrate collected?
The filtrate can be drawn into a separate receiver connected to a vacuum pump or transferred from below the filter plate using a pneumatic diaphragm pump.
6. How is wet cake removed?
Small batches may be removed manually. For easier unloading, HJCHEM can provide a liftable and tiltable vessel. Larger or heavier cakes can be handled using a hydraulic lifting trolley with a stainless steel material tray.