Perchloric Acid Fume Hood

PRINCIPLE

Circulating Water Dilution System for Perchloric Acid Fume Hoods

During experiments in perchloric acid fume hoods, aerosol release of perchloric acid may occur. Ventilation at a rate of 1300 CMH is required. Perchloric acid reacts with the alkaline water behind the deflector as follows: HClO4 + NaOH → NaClO4 + H2O. The neutralized product has a pH value ranging from 7 to 14. The recycling system is made of corrosion-resistant materials.

There is a buffer tank at the bottom of the fume hood, connected to a PP water pump, which is further connected to the atomization pipe. The pump converts the alkaline liquid into droplets to mix with the perchloric acid gas, and the reaction product returns to the buffer tank by gravity.

OPERATION PROCESS

BEFORE USE

Fill the water tank with 50% NaOH solution, measure the pH value and record it.

Ensure that all valves in the circulating water system are open. Do not start the pump if its valve is closed.

Confirm that the perchloric acid experiment in the fume hood is ready. The fume hood should have the rated exhaust volume (the average surface wind speed is between 0.5 and 0.8 m/s, measured by an anemometer).

Press the pump start button, and the circulating water will be distributed in the form of droplets behind the deflector.

AFTER THE EXPERIMENT

Finish the perchloric acid experiment.

Turn off the pump, test the pH value with a pH test paper and record it. Replace the buffer if the pH value is less than 6.

Close the valve of the water system.

Turn off the exhaust of the fume hood.

PRECAUTIONS

For perchloric acid. Follow its chemical traits and procedures. Avoid high-concentration tests. Alkaline water/circulation system behind baffle neutralizes acid to prevent buildup and reactions. Maybe need secondary neutralization for emissions.

FIRST-AID

Skin: Remove clothes, rinse 15+ min, seek medical help.

Eye: Lift lids, rinse 15+ min, seek medical help.

Inhalation: Move to fresh air, assist if needed, seek medical help. Ingestion: Rinse mouth, drink milk/egg white, seek medical help.

MAINTENANCE

If pump leaks, stop experiment, call for repair.

Clean buffer tank sludge regularly.

Don't idle pump without liquid.

Don't operate pump with closed valve.

Don't operate pump with solution over 50 °C.

SPECIFICATION

• Fume Hood Body: 0mm high-quality PP sheets, acid & alkali resistant, weatherproof, welded. Double-layer with ~100mm interlayer for pipelines, ensuring airtightness. Tabletop on bottom cabinet, upper cabinet above. (Exhaust pipe part of bottom cabinet can be suction type.)
• Baffle: Same material & thickness as body. Installed to evenly distribute exhaust, no dead corners. Standard: ~50±10% exhaust ratio at upper, middle & lower outlets, suits different gases. Middle & lower air volume meets experiment needs. (Same type & size baffles interchangeable.)
• Baffle Mounting Bracket: Acid & alkali resistant PP molded assembly.Easy front assembly, disassembly, maintenance & cleaning;  Metal screws (if used) hidden & isolated from cabinet gas. Back plate bracket has distillation grid kit holes. Lock & tighten to fix stainless tube bracket for kit installation.
• Vertical Sash: Acrylic glass, wrapped edges. Plastic inclusive track. Double synchronous cables each side, safe for long-term use. - Single counterweight box, limited travel track.
• Exhaust hood: PP conical constricted gas collecting hood, bottom rectangular opening. ≥50mm connecting pipe height, easy duct connection. Good gathering angle & smoothness, ratio ≥2:1, cone angle ≥30°, for uniform gathering & low pressure loss.
• Lighting: Equipped with LED 30W purification lamp, the luminosity is greater than 300LUX.
• Controller: Intelligent switch with digital display, multiple controls such as power on, fan, lighting, socket, pump, sterilization, damper, etc.