Skip to main content
Thermo Fisher Scientific

Choosing samples and solvents

When selecting samples and solvents, avoid potentially dangerous materials.

Corrosives, solvents and pressurized gases

Many standard spectroscopy methods are based on the use of solvents. Others involve corrosive samples or pressurized samples in a gaseous state. All these sample materials can be measured using your spectrometer, but special precautions must be taken.

 

Avoid explosion hazard.

Never use a flammable gas to purge an instrument. Heat from the source or from laser absorption could ignite the gas. The purge gas must be free of moisture, oil, and other reactive materials. Use dried air or nitrogen to purge the instrument. Other gasses, even inert gasses such as argon (AR), can damage the instrument.

Volatile samples

If you use volatile solvents regularly, follow these guidelines.

  • Do not leave exposed solvent in the sample compartment for longer than necessary.
  • Do not leave the solvents near the instrument.
  • Be sure that your work space is properly ventilated.
 

Avoid fire and explosion hazard.

Prevent fire and explosion. The infrared source inside the instrument is an ignition source. If you are using volatile solvents, provide a fume hood or other active venting system that is free of spark and other ignition sources and prevents flammable vapors from collecting in the atmosphere surrounding the instrument.

These measures will help prolong the life of your instrument and will eliminate the possibility of spectral interference caused by volatile solvent vapors.

Solvents containing halogenated hydrocarbons

Chlorinated solvents, perfluorochlorinated solvents, and other solvents containing halogenated hydrocarbons are often used as sample solvents. The pyrolysis of these solvents by an infrared source or by excessive heating caused by laser absorption may produce hydrochloric acid (HCl), hydrofluoric acid (HF), or phosgene (COCl2). 

Materials such as hydrochloric acid and hydrofluoric acid are highly corrosive and may cause accelerated corrosion of the metallic and optical components in the spectrometer.

A high concentration of corrosive gasses in the air due to improper sampling techniques will damage the instrument.

 

Avoid toxic inhalation hazard.

Materials such as hydrochloric acid, hydrofluoric acid and phosgene are highly toxic. If you regularly use solvents containing halogenated hydrocarbons, be sure your work area is properly ventilated.

  • Was this article helpful?