Cylinderized Phosphine Gas

March 2024 Edition

By:  Jeff Waggoner, ACE

Phosphine gas is the most widely used fumigant in the world.  $Billions of commerce, commodities and structures globally are protected by the proper use of this valuable gas.  It is generally considered an environmentally safe alternative to other fumigants like methyl bromide.  If you are not in the fumigation business, then you might be shocked by how many industries are impacted by fumigation and more specifically by the use of phosphine. 

There are two main types of phosphine.  There are the solid formulations of aluminum phosphide and magnesium phosphide, which are solids that break down into a gas through hydrolysis, a chemical reaction that happens when the solid is exposed to atmospheric humidity.  The actives behave differently.  Magnesium products react faster than aluminum formulations.  This just means that the prior generates phosphine levels faster than the latter.  These reactions are ideally a slow controlled reaction that when dosed properly and applied safely slowly increase the concentration of phosphine in the target space until they are “spent”.  This means that once the reaction is complete, then it slows and eventually stops releasing more gas.  There is a lot more to that given temperature, humidity, etc.  We don’t have time to go into much greater detail than that.  Just know that with the presence of humidity, this is the catalyst for the reaction.  Well, yes, if there is water present, then…. you guessed it.  A MUCH faster reaction.  This can be bad.  If you have worked with solid phosphine products, then you are more than likely aware of the risks and may have even witnessed the results first hand.  I hope everything is ok…

The use limitations and hazards associated with solid phosphine products created a market demand for a more controlled and less risky method of fumigating with phosphine.  There are currently several cylinderized products on the market.  Syensqo (formerly Solvay) has two solutions in their portfolio.  ECO2Fume® and VaporPH3os®.  Degesch America just recently announced the release of their cylinderized product called U-PHOS®.  VaporPH­3os® and U-PHOS® are similar in that they both require specialized application equipment to apply the product.  Think of these products as concentrated phosphine that must be diluted to be used safely.  The other product currently on the market is a ready-to-use cylinderized product called ECO2Fume®.  This product is already diluted and safe for application right out of the cylinders.

You might be asking, what makes one product ready to use and the other one not?  Well, phosphine gas has a unique property.  Over 17,900ppm +/-, phosphine gas can spontaneously ignite in air.  The concentrated formulations are 99%+ pure phosphine in the cylinder.  At that concentration, the product is well above the lower flammability level.  You MUST use some kind of approved equipment for these products.  This does require specialized training and a keen awareness of the product.

The advantage of cylinderized phosphine includes the following:

 

  • Environmental
  • Faster Applications
  • Reduced Exposure Times
  • Reduced Hazards for Use
  • Residues Eliminated
  • Disposal Eliminated

 

Environment – Phosphine rapidly degrades in the atmosphere and is not considered harmful to the environment.

Faster Applications – Since you are not waiting on the chemical reaction to create phosphine, you are able to reach target concentrations quickly.

Reduced Exposure Times – Since you have higher levels faster, you can begin controlling the pests at an earlier time reducing your overall exposure time by sometimes 24-48 hours.

Reduced Hazards for Use – The chemical reaction of solid formulations produces heat.  Under high moisture conditions or when exposed directly to water, these reactions may generate enough heat to catch fire.  Using the proper application equipment with the concentrated products or the pre-blended product eliminates this risk.  Note:  There is some risk associated with the use of any high concentration of phosphine.  In the application process, however, these issues are contained.  There is also the possibility that a cylinder valve may malfunction.  This issue is very rare and cylinders are meticulously maintained by manufacturers.

Residues Eliminated – After the use of pelletized aluminum phosphide there is a residue left behind.  There are several pre-packaged products using aluminum and magnesium that will retain this dust.  Cylinderized products do not leave any residue behind after aeration is completed.

Disposal Eliminated – Pre-packaged products must be disposed of after use.  There is a process for deactivation and disposal but cyliderized products do not require any disposal.  The empty cylinder is returned to the manufacturer for processing and reuse.

While there are many advantages to using cylinderized phosphine products and our options are increasing, users must still consider the following:  Is the product the right choice for your particular use pattern?  Target structure, application limitations, time constraints, half-loss, temperature, humidity, cost, residue issues, aeration limitations, etc. are all things that you should discuss with a reputable fumigation service provider.  Your provider must demonstrate a firm grasp of these products, their dosages, limitations, advantages, application process and most importantly the associated safety precautions that must be taken when handling any fumigant. 

Fumigation is the most effective tool available to combat product loss due to pests.  It can be done safely, effectively and at a price that will return dividends on your investment.  Visit www.FSSzone.com for more information or to contact a representative regarding the use of phosphine.