decomposes at 50-60 °C
Nitroglycerin was first prepared by a scientist named A. Sobrero around 1847 where it was used as a medicine. It was then mass produced by the great scientist Alfred Nobel in 1864 when he developed improvements on its synthesis and a method of detonating it. The devastation nitroglycerin caused on both the battlefield and the factory earned Nobel the title "Merchant of Death." Nobel was haunted by the lives nitroglycerin claimed so he created the Nobel Peace Prize to honor champions of peace, and later, supreme accomplishments in science. His exposure to nitroglycerin gave him constant agonizing headaches, and ironically he took nitro pills for a heart condition later in life. Nitroglycerin remains in use as a medicine, but not for explosives. Nitroglycerin is a very unstable high explosive compound. The first time I tried to make nitroglycerin was back in my early undergraduate days. I was impatient and decided to make some in the dorm without observing proper safety procedures. I was out of ice. Let me just say how important it is to keep this lab cool and slow. Nitrogen dioxide, a dense red-brown gas that is very deadly, it is the reward for nitro gone wrong. I used cool water instead of ice because I never believed all those warnings. Now I do. I began slowly adding the glycerine - not a change on the thermometer. I figured what the hell, I squirted all the glycerine in, stirred it up, checked for a temperature rise, and removed it from the coolant water. I set it on the dresser and stepped out for a minute. When next I looked down the hall and into my back bedroom, a plume of red smoke and acid was shooting out of the flask with increasing intensity. I knew immediately what trouble I was in. My dorm was in a pressurized building so no windows open, that means no ventilation. I rushed in to grab my gas mask and back out to evacuate my neighbors, except the faggot next door of course, who shared nearby rooms. To make a long story short I earned myself a reputation as a potentially dangerous individual and now have small holes in most of my shirts because my laundry was nearby. Read the Safety section again. This disastrous decomposition is about the worst thing that can happen during the nitration, only very large industrial quantity batches risk detonation from runaway nitration. Nitroglycerin has more names than most, they include its proper name of glycerol trinitrate as well as 1,2,3-propanetriol trinitrate; glyceryl trinitrate; glycerol nitric acid triester; nitroglycerol; trinitroglycerol; glonoin; trinitrin; blasting gelatin; blasting oil; S.N.G.; Adesitrin; Angibid; Angiolingual; Anginine; Angorin; Aquo-Trinitrosan; Cardamist; Cordipatch; Coro-Nitro; Corditrine; Deponit; Diafusor; Discotrine; Gilucor; GTN; Klavikordal; Lenitral; Lentonitrina; Millisrol; Minitran; Myoglycerin; Nitradisc; Nitran; Nitriderm-TTS; Nitro-Bid; Nitrocine; Nitrocontin; Nitroderm TTS; Nitrodisc; Nitro-Dur; Nitrofortin; Nitrogard; Nitro-Gesanit; Nitroglin; Nitroglyn; Nitroglyn; Nitrolan; Nitrolande; Nitrolar; Nitrolent; Nitrolingual; Nitro Mack; Nitromex; Nitronal; Nitrong; Nitro PRN; Nitrorectal; Nitroretard; Nitrosigma; Nitrostat; Nitrozell-retard; Nysconitrine; Percutol; Perlinganit; Reminitrol; Suscard; Sustac; Sustonit; Transderm-Nitro; Transiderm-Nitro; Tridil; Trinalgon; Trinitrosan; and Vasoglyn. That is quite a list, most are drug names though.
|sodium carbonate||1000-mL Florence flask|
|sodium chloride||graduated cylinder|
|sulfuric acid||separatory funnel|
Prepare a mixture of 200 mL of 98-100% nitric acid and 300 mL of 98-100% sulfuric acid by slowly adding one to the other in a 1000-mL beaker. Place the beaker into a salt-ice bath during the mixing so it may cool, allow the temperature to drop below 10 °C after mixing. You can keep the cold acid in the salt-ice bath or you can transfer the acid mix into a round-bottomed 1000-mL Florence flask for better heat dispersion. In either case, prepare a fresh salt-ice bath. Because of the possibility of friction, standard stirring methods are not advised. Instead, use an aquarium pump to blow air into the acids as a means to cool and stir them. Regulate the air flow so the acid is being well stirred yet not spattering out. Using a buret suspended above the flask, very slowly add drop by drop 112 mL of glycerol that has been previously cooled to 15 °C. Carefully monitor the temperature of the reaction at all times, the temperature must stay below 20 °C, preferably below 15 °C for extra safety. If at any time the temperature goes near this, stop adding glycerin until it cools. You can use the rate of addition to control the temperature. If the temperature ever rises above 20 °C it is ruined as no more nitro will be made and you are in great danger of the existing nitro detonating. If the temperature goes above 30 °C, there is a sudden rise in temperature, or a red gas is noticed, DUMP IT INTO COLD WATER IMMEDIATELY!. Keep a bucket of ice water on hand for this task. After adding all of the glycerin, allow the temperature to drop to 15 °C and sit for 15 minutes. Carefully pour the reaction mix into a large beaker containing an equal volume of room temperature water. Add this mix to a separatory funnel and allow the nitroglycerin to settle out, it will form a layer on the bottom of the funnel. Drain off the nitro layer and keep the acid waste layer for further extraction. Place the nitro back into a clean separatory funnel and add plenty of 38-45 °C water, mix, then separate. Wash the nitro again, then wash with a warm 4% sodium carbonate solution. Wash with warm water three more times. Give it a final wash of concentrated sodium chloride solution, and let it sit one day before separating the layers. Separate and check the nitro for acidity with litmus paper. If it is still acidic keep washing. It must be neutral or it will explode. Dry the neutral nitro over sulfuric acid in a desiccator, this may take several days. You will need a graduated cylinder for measuring liquids, and a thermometer to monitor the temperature.
To extract any nitro that may still be in the waste acid, first neutralize the acid with sodium carbonate solution. Next add an equal volume of chloroform to the neutral waste acid. Mix well then place it into the separatory funnel. Remove the bottom nitro layer and let it stand in the open for one day so the chloroform may evaporate. Add this nitro to the washing process above.
One unit of glycerol will yield about 2.5 of nitro. Exposure to nitroglycerine will cause severe headaches. Keep it cool, the warmer it is the more sensitive it is to detonation. Frozen nitro can not be detonated therefore it is stable BUT partially frozen nitro is extra sensitive! Although nitroglycerin is very dangerous when confined, it is merely flammable when spread out in the open air. Nitroglycerin can be destroyed by boiling in a solution of potassium or sodium hydroxide and ethyl alcohol.
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