ShotBored - 28-11-2022 at 11:47
So I was at a conference recently and one of the speakers lined up was Jesse Sabatini, a renown energetics materials chemist in the U.S Army's R&D
team. For those of you not familiar, he is very well known in the new molecule synthesis realm of energetics.
He was supposed to talk about one of his big projects, but instead decided to talk about an incident that had happened to him 4 or 5 years ago in
which he was almost killed in the laboratory. For safety reasons, I figured this was a great place to share as a reminder that even
non-energetics-based chemistry can have energetic materials present, unbeknownst to even the most experienced chemists.
Essentially, Jesse was doing some work on de-esterification of some polyester (I don't remember what) to form polyols in a dioxane medium. He was
using Lithium Aluminum Hydride (LAH) as his reducing agent.
It started out that he added dioxane to his reactor vessel and purged the system. A quick peroxide test came back negative. LAH was added to the
vessel next, followed by piecemeal addition of the polyester reagent. The next step involved doing a Fieser quench by cooling the rxn vessel, adding
water, NaOH, and some more water to get rid of the LAH. I believe the addition of the water does liberate some H2, which may have compounded his
accident?
Anyways, during the cooling, Jesse reached into the fume hood to raise the clamps (i don't remember why), but this action dislodged the stir bar and
apparently caused it to strike a crust of LAH on the inside of the reaction vessel. The LAH sparked and caused a vapor explosion from the dioxane (and
H2?). Jesse was wearing his safety glasses, a face shield, and cut resistant gloves which saved his eyes and hands, however glass shrapnel badly
damaged his arm above the glove, the flames went up under the face shield and gave him 2nd degree burns all over his head and face.
He summed up the moral(s) of his story:
1. While not conventionally considered an energetic (explosive) material, LAH has a friction/impact sensitivity up there with a primary.
2. EMS on the army facility would NOT enter the building to rescue him due to a perceived "chemical contamination", he had to walk out under his own
strength while bleeding to death...I dont know how this is with the public sector or in other countries, but its chilling to think that an amateur
chemist in trouble could be left to die if EMS decides that a potentially non-existant chemical threat should keep them from entering a contaminated
area.
3. Stop using LAH, use Red-Al
brubei - 28-11-2022 at 13:31
In a lab of my university LAH is also related with an accident. 10g of LAH was used and i don't know how but there was a explosion leading to serious
burns. The student was not wearing any safety equipment expect usual nitrile glove, glasses and coat.
Herr Haber - 28-11-2022 at 13:52
Reading this I am thankful that EMS (firefighters in my case) would have a self contained breathing apparatus.
Sunday is Saint Barb, I have beer to bring to the local firestation and will ask how they would react.