Hi Guys, im back to the forum for long time ago but and i have a much more simple suggestion to make some TNB with a simple lab equipment.
What do you say to that, i hope it will work fine ?
Set up a simple distillation equipment an distillation column and a catalyst mixture of anhydrous Al2O3 and SiO2
powder (ratio 2:1). Now the n-heptane is distilled slowly with a hotplate above 98,42 degrees and the distillation column is heated with a burner up to about 500 degrees. The chilled distillate of the column is dumping of immediately in a preheated 95 degrees hot beaker with a mixture of higher 98 % HNO3 and 98 % H2SO4 (ratio 1:3) , the mix is stirred for three or four hours and the chilled content of the beaker is diltuted with much more distilled water. Use water a water-cooling system when you have.
Let stand the beaker for some hours in a fridge and filter of the fine slight green needles of trinitrobenzene which should have formed. Crystals can be purifyed in a solvent, maybe acetone is feasible but my experience shows aceton and TNB can form inexplosive big granules, maybe anyone can find an useful solvent to purify the TNB.
The stuff should be much more insensible and i mean it can be purifyed when it vaporized. Have fun !

What, exactly, is the purpose of the heptane? I remember a supposed method to get all the way to TNT using 60% nitric acid (the few people who tried didn't have good results) that utilized the azeotrope of hexane (or cyclohexane?) with water to remove water from the nitrating mixture.

US2435314 Method of nitrating organic compounds (http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=US2435314&F=0)

I don't understand the high boiling point of this composition. You would certainly start boiling off unreacted benzene if you were to quickly heat the reaction to the specified temperature.

It's possible that he means 'reflux' instead of distill in some cases, but then I see no point to using the heptane, unless it was to dilute a thick mixture.

A detailed process to the n-heptane cracking or a useful catalyst for the home lab is not easy to found. N-heptane is fabricated when petroleum is cracked into n-heptane and this into methylcyclohexane. Methylcyclohexane gives toluene, the temperature and the catalyst is important.
I would mean it works.
The content of the diluted acid mixture shows the result. TNT is easy to indicated when some slight yellow hard cake will form.

C7H16 --> C7H14 + H2 --> C7H8 + 4H2
C7H16 --> C6H12 + C + 3H2 --> C6H6 + 3H2

You can make it pure by distillation before it nitrated.

Benzene, boiling point around 80,1 degrees celsius
Toluene, boiling point around 110,6 degrees celsius

Industrial plants using a platinum catalysts for the petroleum cracking. Platinum is expensive, i don`t know if you can buy some platinum wool.

A somewhat more cleaner process is surely when you pass some fresh distilled cyclohexane over a 500 degrees Celsius hot platinum catalyst, the distillate is maked pure by distillation above 81 degrees celsius and is then nitrated with 98% H2SO4 and 80 or 90% HNO3 to trinitrobenzene.

C6H12 --> C6H6 + 3H2

The acid mix is than dumped into icy water and the crystals of TNB should form.