REVISED VERSION

Cheap and Simple Decomposition of 2,4,6-

trinitrotoluene and other industrial pollutants

using pigment derivatives and visible light

Benjamin Lukas

Introduction

TNT or trinitrotoluene is a yellow colored solid chemical which is made

of carbon, hydrogen, oxygen and nitrogen atoms with a formula of

C7H5N3O6. It is a highly explosive chemical but with a convenience

handling properties with a melting point of 80.35 C and a boiling point

of 240 C with a molecular mass of 227g/mol.

The explosive yield of TNT is considered as the standard explosive

strength for bombs and other explosives

C7H5N3O6 7CO + 3N2 + 5H2O + 7C

C7H5N3O6 3N2 + 5H2 + 12CO + 2C

Molecular Structure of TNT

Production of TNT

TNT is produce in industry by nitration process of toluene in three steps :

- In the first step, toluene is nitrated with a H2SO4 mixture of and HNO3 to

produce mononitrotoluene ( MNT)

- MNT is separated and renitrated in second step to produce dinitrotoluene

(DNT)

- In the third step, DNT is reacted with anhydrous mixture of fuming nitric acid

and oleum to produce crude trinitrotoluene (Crude TNT)

Crude TNT is then purified by washing with Na2SO3 in order to remove less

stable isomers of TNT and unwanted products from TNT.

Pure TNT obtained from sulfitation process is then washed with water, the rinse

water is called the red water, a pollutant, which needs to be treated

PRODUCTION of TNT

Properties of TNT

There are 2 main properties:

1. TNT is Explosive

2. TNT is toxic causing:

- Skin irritation with the skin turn bright yellow

orange colors hence called cannary skin.

- Anemia

- Abnormality liver functions

- Reduced male fertility

- Probable carcinogen

Production Problems

Red Water

• For every pound of TNT produced, 1.5 gallons of

toxic/hazardous waste “red water” is generated

• Many countries have not made TNT because of

the difficulty and expensive in treating “red water”.

• An easy and inexpensive way to treat “red water” is needed to allow for TNT production.

Production Problems

Pink Water

• Some countries have tons of unexploded outdated TNT in storage

• Demilitarization of these energetic explosives produces millions of gallons of waste water called pink water which must be treated before the water can be released to environment of water treatment facilities.

• Current demilitarization explosives neutralization procedures are expensive in both their hardware and operating costs.

SOLUTION to the PROBLEMS

• Treat “red” and “pink” water waste streams with pigment derivative which act as photocatalyst to destroy the hazardous compounds with the help of visible light and air.

• As photocatalyst is reuseable the cost of this is very cheap.

• O2 is supplied in the water

HOW DOES A PHOTOCATALYST WORK?

Light is absorbed by the material. In our case,

blue and red light are absorbed by the catalyst

promoting the catalyst from its ground state to

excited state.

The activated catalyst then reacts with the O2 to

produce reactive oxygen species which reacts

with undesired compounds (pollutants) breaking

them down into harmless components..

Pollutants that can be broken down

to gases

• TRI NITRO TOLUENE (TNT)

• DI NITRO TOLUENE (DNT)

• MONO NITRO TOLUENE (MNT)

• BENZENE

• TOLUENE

• DINITROBENZENE

• NITROBENZENE

• PHENOL AND ITS DERs such as Hydroquinone etc

WHAT LIGHT SOURCES

CAN BE USED?

• Other commercial catalyst can

only be activated using only

Blue light but for our catalysts Blue and Red

lights can be used at the same time.

• The best light source is sunlight but other visible

light source such as any headlamp can also be

used.

• The intensity of blue and red lights of sunlight

vary with time.