Solvent-Resistant Diaphragm Vacuum Pump

What is the Solvent-Resistant Diaphragm Vacuum Pump?

A solvent-resistant diaphragm vacuum pump is built with a fully PTFE wetted path and reinforced diaphragms for pumping aggressive solvents and acidic vapors without oil. It is used for concentration, drying and filtration in chemical laboratories.

Overview

This diaphragm pump is designed for chemically aggressive duty. All parts that contact the vapor are made from PTFE or a fluoropolymer, including the pump head, valves and diaphragm, so solvents such as dichloromethane, acetone, alcohols and dilute acids do not corrode the pump. Multi-stage heads push the ultimate vacuum down to about 2 to 8 mbar, close to rotary vane performance but without oil or oil mist. Free-air flow ranges from 20 to 120 L/min. A gas ballast or purge port helps carry condensable vapor through the pump, and the exhaust can be routed to a fume hood or scrubber. Because the pump is dry, there is no oil to change and no risk of oil backstreaming into the sample. Diaphragms are still consumable and should be replaced when vacuum performance falls. These pumps suit laboratories that want deep, clean vacuum for solvent work.

How does it work?

A laboratory vacuum pump removes gas from a sealed vessel to lower the pressure. Diaphragm pumps flex a membrane with check valves, drawing gas in and expelling it without oil, which suits filtration, aspiration and general laboratory work. Rotary vane pumps use an eccentric rotor with sliding vanes to trap and compress gas, giving a deeper vacuum for rotary evaporation and drying, but they need oil and protection against solvent vapor. Water aspirators use a Venturi effect in flowing tap water and are inexpensive but consume water and reach only a modest vacuum. In each case the pump is matched to a receiver, trap and gauge, and solvent or acid vapor must be trapped before it reaches the pump. Flow rate, ultimate pressure and chemical compatibility define performance.

What are the key features?

• Fully PTFE or fluoropolymer wetted path
• Ultimate vacuum of about 2–8 mbar without oil
• Free-air flow of 20–120 L/min
• Gas ballast or purge port for condensable vapor
• Exhaust routable to hood or scrubber
• Reinforced diaphragms for aggressive solvents

What are the technical specifications?

A typical solvent-resistant diaphragm vacuum pump configuration offers ultimate vacuum of 2–8 mbar, free-air flow rate of 20–120 L/min, number of heads of 2 or 4, wetted material of PTFE and fluoropolymer, gas ballast of Yes and motor power of 180–550 W. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The Solvent-Resistant Diaphragm Vacuum Pump is used in solvent concentration and rotary evaporation, vacuum drying of solvent-containing samples, vacuum filtration of organic solutions, degassing of aggressive liquids and centrifugal concentrator vacuum supply. Across the wider Vacuum Pumps class, laboratories also deploy it for vacuum filtration and solid-phase extraction, rotary evaporation and solvent recovery and vacuum oven drying and degassing.

Which standards and certifications apply?

Relevant standards and methods include IEC 61010-1, IEC 61326-1, ISO 21360, EN 12469 and GB 4793.1. Certification candidates for this model are CE, RoHS and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Always fit a liquid trap between the vessel and the pump so that condensate or foam cannot enter the pump head. For solvent work, add a cold trap or an acid-resistant inline filter and change the pump oil regularly, watching for discoloration or emulsion. Vent the exhaust away from the operator when pumping hazardous vapors. Check diaphragms and valves on the maintenance schedule, since they are the usual wear points, and keep spare parts. Mount the pump on a stable surface with adequate ventilation, and confirm the electrical supply and, where required, use a pump rated for the ambient conditions. Follow IEC 61010-1 for electrical safety. Verify the achieved vacuum with a gauge rather than assuming the rated value, and record it for method consistency.

How do I select the right Solvent-Resistant Diaphragm Vacuum Pump?

Choose a solvent-resistant diaphragm pump when aggressive vapors must be pumped to a fairly deep vacuum without oil. For gentle filtration only, a standard diaphragm pump is sufficient. In the RFQ, state the solvents, required vacuum and flow, connection type, and whether exhaust scrubbing is needed.

How does it compare with other Vacuum Pumps variants?

Choose by the required vacuum level and the vapor being pumped. For filtration, aspiration and vacuum concentration where a moderate vacuum is enough, an oil-free diaphragm pump is usually the right choice, because it needs little maintenance and cannot backstream oil. For rotary evaporation, gel drying and vacuum ovens that need a deeper vacuum, a chemically resistant rotary vane pump with a cold trap and oil mist filter works well. Use a water aspirator only where tap water is available and water use is acceptable. Then match the free-air flow rate to the system volume and the speed of operation you need, and confirm the pump can start against the load. Check wetted materials and diaphragm or vane materials for solvent and acid compatibility, noise level, and whether a gauge, regulator or vacuum controller is included.