On 4th August 2020, a massive explosion occurred at Beirut port killing over 100 people till now and injuring more than 4000 people. It shook the capital city of Lebanon spreading grief all across the world. Many countries have also extended their support to Lebanon to help them cope with the disaster. What was the cause of such a massive explosion? According to the government of Lebanon, over 2,700 tonnes of ammonium nitrate was kept in storage at the Beirut port for 6 years that resulted in the blast. What is ammonium nitrate and how is it used? Let’s read in detail.
What is Ammonium Nitrate?
Ammonium nitrate is a chemical ingredient mainly used in agricultural fertilisers. The nitrogen-rich compound is also the main element of the explosive composition known as ANFO — ammonium nitrate fuel oil. The compound is also known for its oxidizing powers. It is extensively used to build explosives used in the mining and construction sectors. The formula for ammonium nitrate is NH4NO3 which is a white, crystalline chemical in its pure form. Pure ammonium nitrate is not an explosive, however, when mixed with other elements such as fuel and external factors, it can explosive in nature.
Many Improvised Explosive Devices (IEDs) used by terrorists to create explosives around the world have ANFO as the main explosive, that is triggered by primary explosives like RDX or TNT. In the majority of terror attacks happened in India over the past decade, including those in Pulwama, Delhi, Hyderabad, and Mumbai, ammonium nitrate has been a the primary explosive along with initiator explosives like RDX.
Physical Properties of Ammonium Nitrate
- It is a crystalline solid in its purest form and has a white/grey colour.
- It has a trigonal crystal structure.
- It is soluble in water with its solubility at 20oC is 150g/100ml.
- The dissolution of NH4NO3 in H2O is a highly endothermic reaction.
- It has a very low shock and friction sensitivities.
Chemical Properties of Ammonium Nitrate
- On the reaction of NH4NO3 with the hydroxides of alkali metals, the nitrates of alkali metals are formed with ammonia.
- Upon heating of ammonium nitrate, it decomposes and forms nitrous oxide (N2O) & water.
- On explosion, ammonium nitrate yields N2, O2, and water as the by-products.
- Despite being a major component of many explosives, ammonium nitrate does not act as an explosive by itself. It must be mixed with other primary explosives to form an explosive mixture.
Ammonium Nitrate Regulations in India
As Ammonium nitrate can be misused by scrupulous elements of the society for making explosives, it is highly regulated in India to prevent mishandling. The compound is widely used in the manufacture of industrial explosives, fertilisers, anaesthetic gases, cold packs and is more likely to be misused. Hence, The Ammonium Nitrate Rules, 2012 cover the manufacture, export, transport, conversion, bagging, import, possession for sale or use of ammonium nitrate. It is even illegal to store large amounts of this compound in popular or crowded areas. An Industrial licence is required under the Industrial Development and Regulation Act, 1951 for activity dealing with ammonium nitrate.