Organic Chemistry
Beirut Explosion Case
By: Pragya
1) Carbon- carbon Sigma Bond
2) Chemistry of alkanes
3) Formation of alkanes
4) Wurtz Reaction
5) Wurtz Fittig Reaction
6) Ammonium nitrate
7) Properties
8) Application
Contents
9) Storage and handling
10) CASE STUDY- Beirut Explosion
11) Overview
12) Background
13) Explosion
14) Cause
15) Casualties
16) Damage
17) Investigation
18) Relief operation
19) Conclusion
20) Referncess
Carbon – carbon sigma bond
A carbon–carbon bond is a covalent bond between two carbon atoms.
The carbon–carbon single bond is a sigma bond.
It is formed between one hybridized orbital from each of the carbon atoms.
the carbon atoms in the single bond need not be of the same hybridization.
Carbon atoms can also form double bonds in compounds called alkenes or triple bonds in compounds called
alkynes. The use of the p-orbitals forms a pi bond.
• Sigma bonds are a result of the head-to-head overlapping of atomic orbitals whereas pi bonds are formed by
the lateral overlap of two atomic orbitals. Various bond parameters such as bond length, bond angle, and
bond enthalpy depend on the way the overlapping of atomic orbital takes place. The electrons participating in
a σ bond are commonly referred to as σ electrons.
• They can be formed by :-
i. s – s overlapping
ii. S – p overlapping
iii. P – p overlapping
CHEMISTRY
OF
ALKANES
CHEMICAL PROPERTIES OF
ALKANES:
Alkanes are only weakly reactive with most chemical compounds
they are extremely weak acids that are practically inert to bases (carbon acids). They are also
extremely weak bases, undergoing no observable protonation.
they are also relatively unreactive toward free radicals, although many electron-deficient
radicals will react with alkanes in the absence of other electron-rich bonds.
FEW REACTIONS OF ALKANES INCLUDED:
REACTION WITH OXYGEN
REACTION WITH HALOGENS
CRACKING
ISOMERIZATION
REACTION
WITH
OXYGEN
All alkanes react with oxygen in a
combustion reaction, although they
become increasingly difficult to ignite
as the number of carbon atoms
increases.
Inthe absence of sufficient
oxygen, carbon monoxide or even
soot can be formed.
REACTION WITH HALOGENS:
• Alkanes react with halogens in a so-called free radical halogenation reaction.
• The hydrogen atoms of the alkane are progressively replaced by halogen atoms.
• The reaction is highly exothermic with halogen fluorine and can lead to an explosion.
• These reactions are an important industrial route to halogenated hydrocarbons. There are three
steps:
1. Initiation the halogen radicals form by homolysis. Usually, energy in the form of heat or light is
required.
2. Chain reaction or Propagation then takes place—the halogen radical abstracts a hydrogen from
the alkane to give an alkyl radical. This reacts further.
3. Chain termination where the radicals recombine.
CRACKING:
Cracking breaks larger molecules into smaller
ones. This can be done with a thermal or
catalytic method. The thermal cracking
process follows a homolytic mechanism with
formation of free-radicals.
Carbon-localized free radicals and cations are
both highly unstable and undergo processes of
chain rearrangement, C–C scission in position
beta (i.e., cracking) and intra- and
intermolecular hydrogen transfer or hydride
transfer.
ISOMERIZATION
Inisomerization, the alkanes
become branched-chain
isomers. In other words, it does
not lose any carbons or
hydrogens, keeping the same
molecular weight.
Formation of alkanes
From Unsaturated Hydrocarbons
(Sabatier and Senderens Method)
By Salts of Carboxylic Acid or DECARBOXYLATION
Alkanes can be prepared from salts of carboxylic acids. One of these methods include Kolbe’s
electrolytic method.
•Kolbe’s Reaction
RCOONa -> RCOO + Na
- +
RCOO gains electrons and forms unstable RCOO which gives R-R (alkane) and carbon dioxide
-
gas. By Metal Carbides
3.BY METAL CARBIDES:-
Be2C + H2O ->CH4 + Be(OH)2
Wurtz Reaction
• The Wurtz reaction, named after Charles Adolphe
Wurtz, is a coupling reaction in organic chemistry,
organometallic chemistry and recently inorganic
main-group polymers, whereby two alkyl halides are
reacted with sodium metal in dry ether solution to
form a higher alkane. In this reaction alkyl halides
are treated with sodium metal in dry ethereal (free
from moisture) solution to produce higher alkanes.
It is also used for the preparation of higher alkanes
containing even number of carbon atoms:
2 R−X + 2 Na → R−R + 2 Na+X−
WURTZ FITTIG REACTION
The Wurtz–Fittig
reaction is the
chemical reaction of
aryl halides with alkyl
halides and sodium
metal in the presence
of dry ether to give
substituted aromatic
compounds.
WHAT IS AMMONIUM NITRATE?
Ammonium nitrate is a
chemical compound with the
chemical formula NH₄NO₃. It
is a white crystalline solid
consisting of ions of
ammonium and nitrate. It is
highly soluble in water and
hygroscopic as a solid,
although it does not form
hydrates.
OCCURANCE OF AMMONIUM NITRATE
Solid ammonium nitrate decomposes
on heating. At temperatures below around 300
°C, the decomposition mainly produces nitrous
oxide and water: ... Many ammonium nitrate
disasters, with loss of lives, have occurred. The
red–orange colour in an explosion cloud is due
to nitrogen dioxide, a secondary reaction
product.
PROPERTIES
Physical and chemical properties
Ammonium nitrate is crystalline in nature .
The dissolution of ammonium nitrate on h2o is highly endothermic .
The compound has very low shock and friction sensivities.
When NH4NO3 reacts with alkali hydroxides, not only ammonia but also
alkali nitrates are formed.
Odorless
The melting point of Ammonium nitrate is 442.8K (169.6°C) and the
boiling point is 483K (210°C)
Ammonium nitrate has the detonation power of 2500 velocity per
second.
Produced in small porous pills and granules form .
It is the source of oxygen which can be used to induced combustion
of other material .
It also can decomposes at the high room temperature .
It produces nitrogen gas which is the major risk factor for the
respiratory system
APPLICATIONS
•Commonly used in fertilizers.
•Also used in the manufacture of nitrous oxide.
•Used as an absorbent.
•Used as an ingredient an oxidizer in
rocket propellants.
•Act as a good nutrient for yeast and antibiotics.
•It is also used in explosives.
•Nitrates are used to cure meats.
STORAGE AND HANDLING OF
AMMONIUM NITRATE:
Ammonium nitrate should normally be stored in single storey, dedicated, well-ventilated
buildings that are constructed from materials that will not burn, such as concrete, bricks
or steel.
In some circumstances, such as where the stores are located near to densely populated
areas, it may be better to store ammonium nitrate outside, provided it is in a secure area
away from combustible materials and sources of contamination. Such outdoor storage
can remove or reduce the risk of, for example, fires due to electric lights and other
equipment.
Locate storage away from possible sources of heat, fire or explosion, such as oil storage,
gas pipelines, timber yards, flammable liquids, flammable solids and combustible
materials.
Do not store ammonium nitrate in the same building as incompatible materials. The risk of fire or explosion is
increased if ammonium nitrate is mixed with combustible or incompatible materials (including when molten in a
fire) such as:
• Flammable or combustible liquids such as petrol, diesel, oil, grease, paint, carbonaceous material.
• Pressure vessels and gas cylinders.
• Oil based pesticides.
• Organic matter, such as hay, straw, grain and animal feedstuffs.
• Sulphur.
• Corrosive liquids, acids, alkalis and other reactive substances (oxidising or reducing) such as chlorates,
hypochlorites, bleaching powder, nitrites, copper or chromium salts, chromates, permanganates.
• Powdered metals, alkali metals, zinc or galvanised iron, copper or copper alloy.
• Urea.
• Chlorides.
• Products which generate heat in the presence of moisture, such as quick-lime, and calcium cyanamide.
• Products, which will generate ammonia gas from the ammonium nitrate, such as cement, lime, basic slag and other
alkaline substances.
• Other agricultural products whose behaviour towards ammonium nitrate is uncertain, for example branded
pesticides, disinfectants or weedkillers.
Case Study- Beirut Explosion
Overview
•Date - 4 August 2020
•Time - 18:08:18 EEST
•Venue - Port of Beirut
•Location - Beirut, Lebanon
•Type -
Ammonium nitrate explosion
•Cause - Under investigation
•Deaths - 218
•Non-fatal injuries - 7,000+
•Property damage - US$15+ billion
•Displaced ~300,000
Background
•The economy of Lebanon was in a state of crisis before the explosions
•In addition, the COVID-19 pandemic had overwhelmed many of the country's
hospitals,
•The government-owned Port of Beirut serves as the main maritime entry point
into Lebanon.
•The port included four basins, sixteen quays, twelve warehouses,[7] a large
container terminal,[8] and grain silos with a total capacity of 120,000 tonnes that
served as a strategic reserve of cereals for the country.
•On 27 September 2013, the cargo ship MV Rhosus
set sail from Batumi, Georgia, to Beira, MV RHOSUS
Mozambique, carrying 2,750 tonnes of
ammonium nitrate.
•Rhosus was owned by a company based in Panama.
The shipment had been ordered by an African
explosives manufacturing company for mining in
Mozambique.
•On 21 November 2013, the ship made port in Beirut
due to possibly engine problems.
•The heavy machinery stacked on top of the doors to
the cargo space containing the ammonium nitrate,
damaged the ship.
•The Rhosus soon ran out of provisions, and the
remaining crew were unable to disembark due to
immigration restrictions. The Beirut port authority
seized the ship on 4 February 2014, due to
US$100,000 in unpaid bills.
EXPLOSIONS
FIRST EXPLOSION:- the first
explosion, at about 18:07 local time
(15:07 UTC), likely triggered by the
stored fireworks, sent up a large
cloud of smoke and a crackle of
bright firework flashes, and heavily
damaged the structure of the
warehouse itself with a force
equivalent to around 1.5-2.5 tons of
TNT, the size of a mid-sized truck.
FINAL EXPLOSION
The second explosion, 33 to 35 seconds later, was much more
substantial and was felt in northern Israel and in Cyprus, 240
kilometers (150 miles) away.
What caused the explosion?
Authorities say the blast occurred when a fire at a
warehouse—Hangar 12—on the city's waterfront ignited a
cache of ammonium nitrate, an explosive material that had
been stored at the site for more than six years.
• The assumptions made about the fire that ignited the
explosion are:
A. The fire was ignited by workers welding a door at a
warehouse.
B. It "remains unclear ... whether fireworks, ammunition
or something else stored next to the ammonium nitrate
might have been involved" .
C. It could be the combination of fuel oils to create an
explosive used in the mining and construction
industries.
How many people
died in the explosion?
218 people were confirmed dead,
and over 7,000 people were injured.
At least 150 people became
permanently disabled
The explosion also resulted in
ammonia gas and nitrogen oxides
being released into the air,
potentially with toxins from other
materials that may have also ignited
as a result of the explosion.
Damage
•The explosion overturned cars and stripped steel-framed buildings of their cladding.
•Within the port area, the explosion destroyed a section of shoreline and left a crater roughly 124 m
(407 ft) in diameter and 43 m (141 ft) in depth.
•Homes as far as 10 kilometers (6 miles) away were damaged by the blast.
•The grain silos were largely destroyed.
•The damage from the blast affected over half of Beirut, with the likely cost above $15 billion
and insured losses at around $3 billion.
•Approximately ninety percent of the hotels in the city were damaged and three hospitals
completely destroyed.
•Saint George Hospital was so badly damaged.
•The Sursock Museum was severely damaged, as were many of its artworks, and some
ceramics were completely destroyed.[142] The atelier for the fashion house Sandra Mansour
was heavily damaged by the explosion.
• Sursock Palace, a 160-year-old Beirut landmark that was listed as a cultural heritage site, also
sustained heavy damage, as did its many artworexplaion.
Shipping
The cruise ship Orient Queen, berthed nearby, suffered extensive
damage and capsized overnight.
The edible-oil tanker ship Amadeo II, was nearest to the explosion, which
deposited the mangled remains of the ship on a nearby quay.
Airport
Beirut–Rafic Hariri International Airport sustained moderate damage to
the terminal buildings during the explosion.
INVESTIGATION
• Ground warp and buckle after the blast
erupted from the warehouse
• More than 2,750 metric tons of ammonium
nitrate blamed as cause of blast
• Present in the dock since 2013
• Bellingcat said that this explosion could
have been a ship and not an airstrike
• Notable features of the explosion
included reddish cloud and many
small flashes
• Media claimed explosive material
improperly stored at this location
• Customs authority did not
respond to requests to guidance
• Ammonium nitrate is the primary
ingredient in many explosives
• Sacks of Nitroprill are a knock off
version of original
RELIEF OPERATIONS:
• The Lebanese Red Cross said every available ambulance from North Lebanon,
Bekaa, and South Lebanon was being dispatched to Beirut to help
patients. According to the agency, a total of 75 ambulances and 375 medics were
activated in response to the explosions
• Lebanese President Michel Aoun said the government would make up to
100 billion pounds (US$66 million) in aid available to support recovery operations.
• Health Minister Hamad Hasan requested that international aid be sent to
Lebanon; several countries sent in food, medical supplies, field hospitals, medical
workers, and rescue teams.
• Many civil society organizations offered equipment and food to the volunteers,
while many residents and businesses opened their homes and hotels for free to
those who lost their homes in the blast
• UNESCO played a leading role in the rescue and reconstruction of historic
buildings, with Blue Shield International assessing the damage to houses, museums
and libraries, and the International Council of Museums providing expertise.
CONCLUSION
•Ammonium nitrate decomposes, into the gases nitrous oxide and
water vapor when heated. However, it can be induced to decompose
explosively by detonation.
•On August 4, 2020, one of the largest non-nuclear explosions at
Beirut damaged over half the city.
•The explosion resulted from the detonation of tonnes of ammonium
nitrate.
•The blast was felt across Turkey, Syria, Palestine, Israel as well as
parts of Europe, and was heard in Cyprus, more than 240 km away.
•The Lebanese government declared a two-week state of emergency
in response to the disaster.
•In its aftermath, protests erupted across Lebanon against the
government for their failure to prevent the disaster.
References
https://youtu.be/SkIYjNGiaoA
https://youtu.be/hd_unqev_NI
https://youtu.be/yNH4eE3RYUM
https://en.wikipedia.org/wiki/2020_Beirut_explosion
https://www.bbc.com/news/world-middle-east-53668493
https://www.ndtv.com/topic/beirut-blast
