Specifications

Component List

All components listed below are included in this kit. Items marked Optional can be customized.

Available Joint Sizes · GB/ISO/ASTM Standards

All sizes share 1:10 standard taper — GB, ISO, and ASTM sizes are interchangeable

14/19 19/26 24/29 (GB·recommended) 29/32 34/35 · 45/40 · 50/42 custom

GB (Chinese) 14/19 · 19/26 · 24/29 · 29/32 ISO 14/19 · 19/26 · 24/29 · 29/32 ASTM (American) 14/20 · 19/22 · 24/40 · 29/42

* All components have matching joint sizes for full system compatibility. ASTM and GB/ISO sizes share 1:10 taper — seal lengths differ but are interchangeable.

Component	Standard Spec	Available Joint Sizes	Upgrade Options	Qty	Link
Please contact us to confirm the available specifications.

📌 Customization Notes:
• Joint size can be selected to match your existing lab system:
GB (Chinese): 14/19 · 19/26 · 24/29 · 29/32
ISO: 14/19 · 19/26 · 24/29 · 29/32
ASTM (American): 14/20 · 19/22 · 24/40 · 29/42
• Three-neck flask capacity: 250ml (standard), 500ml, 1000ml
• Bubbler: With frit (standard), Without frit
• Upgrade to Schlenk line for vacuum/inert gas switching
• Mix and match — no minimum order quantity

💡 Recommended Add-Ons: Schlenk line · Inert gas cylinder + regulator · Vacuum pump · Vacuum grease

Product Description

I. How Inert Gas Protection Works

Many organometallic compounds, complexes, and reactive intermediates are extremely sensitive to oxygen and moisture — exposure to air for just seconds can cause decomposition, discoloration, or loss of activity. Inert gas protection uses nitrogen (N₂) or argon (Ar) to displace air (oxygen and moisture) from the reaction system, enabling synthesis and handling under an inert atmosphere.

The basic procedure: inert gas is introduced through a delivery tube into the reaction vessel, entering below the liquid surface to displace air from the system. The displaced gas exits through an outlet (bubbler). After purging for 5–15 minutes, oxygen levels can be reduced to below 10 ppm. During the reaction, a positive pressure is maintained to prevent air from entering.

✦ Nitrogen vs Argon:

Nitrogen (N₂): Cost-effective, suitable for most non-sensitive reactions. Not suitable for reactions with metals that react with nitrogen (e.g., lithium, titanium, vanadium).
Argon (Ar): More inert, does not participate in chemical reactions — suitable for all air-sensitive reactions. More expensive than nitrogen, but recommended for sensitive reactions.
When in doubt, use argon — it's the safest choice.

II. What's in the Setup

Three-Neck Round-Bottom Flask — Core reaction vessel; three necks for gas inlet, outlet, and addition/stirring
Gas Delivery Tube (Inlet) — Introduces inert gas; the tube tip extends below the liquid surface
Gas Delivery Tube (Outlet) — Connects to the bubbler for gas exhaust
Bubbler — Exhausts gas and indicates flow status (steady bubbles confirm proper purging)
Rubber Stopper — Seals unused necks
Iron Stand & Universal Clamps — Secures the apparatus
Schlenk Line (optional) — Enables vacuum/inert gas switching

III. Schlenk Techniques

Schlenk techniques extend inert gas protection using a Schlenk line (dual manifold — one for inert gas, one for vacuum) to alternate between vacuum and inert gas. Repeated cycles of evacuation and inert gas refilling (3–5 times) reduce oxygen and moisture levels to below 1 ppm. This kit is compatible with standard joint Schlenk lines — available as an upgrade.

IV. Material & Workmanship

The three-neck flask, gas delivery tubes, and bubbler are all made from borosilicate glass 3.3 — chemically resistant and thermally shock-resistant. All ground joints are precision-machined to the standard 1:10 taper for reliable sealing. The bubbler's frit has uniform pores for fine bubble dispersion and efficient gas exchange.

Applications

Typical Applications

Organometallic Reactions

Grignard reagent preparation, organolithium reagent handling, transition metal catalysis

Schlenk Techniques

Synthesis, transfer, filtration under anhydrous, oxygen-free conditions

Inert-Atmosphere Polymerization

Ring-opening polymerization, coordination polymerization, living polymerization

Air-Sensitive Compound Handling

Complex synthesis, catalyst preparation, sensitive intermediate transfer

Glove Box Sample Prep

Sealing samples and solvents under inert gas for transfer into glove boxes

Flask Volume	Recommended Flow Rate	Purge Time (Gas Only)	Schlenk Cycles
Please contact us to confirm the available specifications.

Compound Type	Reactive To	Recommended Gas	Handling
Please contact us to confirm the available specifications.

Operation & Maintenance

User Guide

The core of inert gas protection is gas purging and maintaining positive pressure. Here are the essential steps.

🚨 Three rules to remember:
① Purge before starting the reaction — inert gas must be flowing before adding reagents or heating
② Always maintain positive pressure — the outlet must never be completely sealed
③ Schlenk operations require repeated cycles — at least 3 cycles for thorough oxygen removal

I. Before You Start

Check all glassware for cracks — cracked glass is unsafe
Check gas connections — rubber tubing for cracks or aging
Confirm inert gas cylinder pressure is sufficient and the regulator works
Confirm the bubbler contains an appropriate indicator liquid (mineral oil or silicone oil)

Assembly sequence

Secure the three-neck flask on the iron stand; center neck for stirrer (if needed)
One side neck for inlet gas delivery tube (tip below or near liquid surface)
One side neck for outlet gas delivery tube (connected to bubbler or Schlenk line)
Seal unused necks with rubber stoppers
Leak check: Flow a small amount of inert gas — steady, continuous bubbles at the bubbler indicate good sealing

III. Gas Purging

Nitrogen/Argon delivery: Connect rubber tubing from the cylinder regulator to the inlet tube — open the cylinder valve and adjust the regulator for slow, steady gas flow (bubbler bubbles at a moderate, continuous rate)
Purge the system for 5–15 minutes (depending on flask volume — 250ml about 5-8 minutes, 500ml+ longer)
After purging, maintain positive pressure (bubbler should always show bubbles)
For Schlenk deep deoxygenation: alternate vacuum evacuation and inert gas refilling — repeat 3–5 times

IV. Addition & Reaction

Maintain inert gas flow during addition — quickly lift the stopper to add solid, or use a syringe through a septum for liquids
Keep positive pressure throughout the reaction — the bubbler should show continuous bubbles
If bubbles stop, gas flow has stopped or the line is blocked — check immediately
For heated reactions, turn on the heating mantle under inert gas protection

V. Shutdown

After the reaction is complete, turn off the heating mantle (if used)
Keep inert gas flowing while the apparatus cools naturally
Once cooled to room temperature, close the cylinder valve first, then disassemble
Important: Disassemble immediately after closing the cylinder — prevents air from entering
Clean all glassware, dry, and store properly

📌 Inlet tube position is critical:

The inlet tube tip must extend below the liquid surface — gas entering from below rises through the liquid, carrying dissolved oxygen out. If the tip is above the liquid, gas merely flows over the surface — oxygen removal is far less effective.
For solid reactants (insoluble), position the inlet tube near the solid surface so gas flows across the solid to displace surrounding air.

💡 From a Seasoned Lab Hand:

"Inert gas protection is all about 'in' and 'out' — steady inflow, clear outflow."
The bubbler is your "eyes" — bubble rate and consistency tell you how the purge is going. Too fast wastes gas and may blow solvent out; too slow means incomplete purging.
Schlenk technique tips: When evacuating, open and close valves slowly — opening too fast can pull solvent into the vacuum pump. After evacuation, refill with inert gas before closing the vacuum valve — the wrong order allows air to enter.
Addition tip: For solids, blow inert gas over the addition port before adding quickly — minimizes air entry. For liquids, use a syringe + septum through the inlet tube's rubber septum.

Care & Notes

Show care & notes

⚠️ Safety & Compliance Checklist

Inert gas purging must be done in a fume hood

— although the gas itself is non-toxic, it displaces oxygen and poses an asphyxiation risk in enclosed spaces

Secure gas cylinders

— prevent tipping

Schlenk evacuation

Watch the liquid in the flask — don't evacuate too aggressively, which can pull solvent into the vacuum pump

Wear gloves and goggles when handling air-sensitive compounds

— many organometallics are toxic or corrosive

Do not

The outlet (bubbler) must never be completely sealed — excess positive pressure can cause glass rupture

Inert Gas Protection Apparatus

Specifications

Component List

Product Description

I. How Inert Gas Protection Works

II. What's in the Setup

III. Schlenk Techniques

IV. Material & Workmanship

Applications

Organometallic Reactions

Schlenk Techniques

Inert-Atmosphere Polymerization

Air-Sensitive Compound Handling

Glove Box Sample Prep

User Guide

I. Before You Start

Assembly sequence

III. Gas Purging

IV. Addition & Reaction

V. Shutdown

Care & Notes

Inert gas purging must be done in a fume hood

Secure gas cylinders

Schlenk evacuation

Wear gloves and goggles when handling air-sensitive compounds

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Inert Gas Protection Apparatus

Specifications

Component List

Product Description

I. How Inert Gas Protection Works

II. What's in the Setup

III. Schlenk Techniques

IV. Material & Workmanship

Applications

Organometallic Reactions

Schlenk Techniques

Inert-Atmosphere Polymerization

Air-Sensitive Compound Handling

Glove Box Sample Prep

User Guide

I. Before You Start

Assembly sequence

III. Gas Purging

IV. Addition & Reaction

V. Shutdown

Care & Notes

Inert gas purging must be done in a fume hood

Secure gas cylinders

Schlenk evacuation

Wear gloves and goggles when handling air-sensitive compounds

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