The Science Behind the Beirut Explosion
The year 2020 ranks among the most eventful, with Australia’s devastating wildfires, a global pandemic, and the withdrawal of the United Kingdom from the European Union to name just a few. The most recent horror of 2020 occurred on Tuesday, August 4, 2020 just after 6PM (GMT). An immense explosion ravaged the capital city of Beirut, Lebanon with effects that could be felt from miles away. According to Lebanon’s Health Minister Ghassan Hasbani the blast tore through Lebanon’s capital city, killing at least 135 people, injuring about 5,000, and leaving an estimated 300,000 individuals homeless. Beirut will have a national period of mourning where citizens will honor the fallen as they attempt to rebuild all that was lost from Thursday, August, 6 until Saturday, August 9.
Beirut’s explosion originated from 2,750 tons of the chemical compound ammonium nitrate (NH4NO3) that had been sitting in a hangar near the Beirut shipping docks since 2013. A Russian - owned cargo ship carrying the ammonium nitrate docked in Lebanon’s capital after experiencing some trouble at sea and deserted the ship. The chemical goods from the vessel were then removed and stored in “...Hangar 12 of Beirut port, a large grey structure facing the country’s main north - south highway at the main entrance to the capital”. There were many inquiries from Lebanese Customs to an unnamed “Urgent Matters judge” as to how to handle the reactive compound, but nothing came out of it. An investigation led by the Lebanese government as to why the ammonium nitrate was not dealt with and why it occurred is now underway as told by their prime minister, Hassan Diab.
Ammonium nitrate or AN was created artificially in 1659, by Johann Rudolf Glauber, a German chemist and is a salt and an oxidizer. Today, AN can be “...used as a fertilizer, as a freezing mixture, in safety explosives, matches, and pyrotechnics” (National Center for Biotechnology Information). Physically, AN can come in the form of white, gray, or brown odorless beads or flakes (National Center for Biotechnology Information). The detonation of AN is usually intentional as it must be set off by either fire or a combustible substance. However, there are records that show AN can combust spontaneously at high enough temperatures on its own (Djerdjev, et al.). If ammonium nitrate makes contact with pyrite (FeIIS2), an exorbitant amount of heat emitted from a geothermal source, or with any carbon - rich fuel such as paper, an explosion may occur (Djerdjev, et al.). The decomposition of ammonium nitrate is an exothermic reaction which means that energy is released to its surroundings in the form of heat, light, electricity, or sound. The chemical formula for the reaction produces three moles of gaseous products for each one mole of reactant (a mole is a chemical unit of measurement used in chemistry) and has an enthalpy change of -36 kJ/mole. Scientists are only able to get the change of a reaction’s enthalpy which is “...the sum of the internal energy of a system plus the product of the system’s pressure and volume”. Since the change in enthalpy is negative, this means that the reaction releases heat which makes it exothermic rather than endothermic.
According to Jimmie Oxley, a chemist from the University of Rhode Island, if the AN in Beirut was stored in cardboard or wood, then it could have exploded because of cardboard or wood’s carbon - rich chemical makeup. Once detonated, AN decomposes and releases toxic gases that have ammonia as well as nitrogen oxides that strengthen an explosion even without the presence of oxygen (National Center for Biotechnology Information). If decomposition occurs in a pressurized space, like a shipping hangar, the pressure could increase to hazardous levels that prompt the explosion of ammonium nitrate (National Center for Biotechnology Information).
The Beirut explosion is not the first of its kind. In 1947, a 2,300 ton ammonium nitrate explosion occurred in Texas City, Texas at a Houston-area port that killed about 600 people and injured more than 5,000 people. In 2001, another AN detonation tore through a factory in Toulouse, France that destroyed much of the city. In 2015, 170 people were killed in Tianjin, China, a port city, because of improper handling of ammonium nitrate. After analyzing the previously mentioned past events, experts recognized a common pattern with AN detonation: inappropriate handling and storage. Since improper storage is such an impactful factor to prevent spontaneous AN combustion, many governments have strict regulations on how to handle the compound. In the United States of America, Coast Guard officials observe and keep track of the ammonium nitrate regularly. In the European Union, officials exercise much caution when it comes to the compound, especially when used in fertilizers. The most recent Lebanon explosion serves as an important reminder of the dangers of chemical compounds and the necessary precautions that comes with handling them.
With so many lives destroyed by the effects of the Beirut explosion, countries and organizations around the world have come to the aid of the Lebanese people. The WHO (World Health Organization) is sending over medical supplies that could subsidize over 1,000 trauma and surgical interventions. France is airlifting “dozens of emergency workers, a mobile medical unit and 15 tons of aid”. Hungary is giving 1 million euros for reconstruction as well as rescue efforts in Lebanon, and multiple other countries are also contributing to the aid efforts While the world is coming to help the Lebanese people, you can help as well by donating or spreading awareness through these links. In a troubling time like 2020, it is critical to stay vigilant of the world around you and assist those who need it the most.
Works Cited:
Djerdjev, Alex M., et al. “The Mechanism of the Spontaneous Detonation of Ammonium Nitrate in Reactive Grounds.” Journal of Environmental Chemical Engineering, vol. 6, no. 1, 2018, pp. 281–288., doi:10.1016/j.jece.2017.12.003
National Center for Biotechnology Information. "PubChem Compound Summary for CID 22985, Ammonium nitrate" PubChem, https://pubchem.ncbi.nlm.nih.govcompound/Ammonium-nitrate. Accessed 7 August, 2020.
