[LT] Ancient Nitroglycerin

[Jinumon]

Hey again,

So, I've had a Fantasy setting I've been working on on-and-off for a few years now. I had an idea for a Medieval Technocracy in which the government is controlled by a small elite who produce a particular "miracle substance." My initial thought was simply Black Powder, but the simplicity of the process for creating Black Powder makes me question the credibility of a nation being able to keep its formulation entirely secret. I mean, yeah, they can take precautions and they aren't going to be giving it away, but if their production is anything other than extremely small-scale, they'll need unskilled laborers to harvest the materials they'll need, and it seems like the basic composition of the substance (saltpeter, sulfur, and charcoal) would be out in a century or two. If this is long-established government whose power is derived from this secret, it doesn't seem like they'd last that long. So my second idea was for them to have discovered the methods for producing Nitroglycerin, a much more lengthy and multi-step process with potentially history-altering consequences. I've tried to do some research on my own, but most of what I've found on the formulation of Nitroglycerin and its required components is far beyond my knowledge of chemistry.

As a simple question to any chemists or chemistry enthusiasts out there: Is it conceivable for a TL3+1 society to produce Nitroglycerin? Are the raw materials available for collection and production, or does it require mechanical or analytical technology far beyond that of a ~14th century society?

I always appreciate you guys. Thanks again,

Jinumon

[Varyon]

Difficult to say. Nitric acid, or aqua fortis, was discovered in the 13th century (TL 3), while glycerol wasn't discovered until 1779 (TL 5). However, the early materials for producing glycerol - olive oil and litharge - would be known before TL 3. If the stars aligned right, nitroglycerin may be doable at TL 3+1, but its instability could result in it likely being abandoned without more modern chemistry safety. Historical uses of the stuff typically involved production more-or-less on-site, as it was too unstable to transport safely, and that's going to make it harder to keep its recipe a secret. Personally, for alternative low TL explosives, I'm a bigger fan of nitrocellulose/guncotton, which can be made with aqua fortis, vitriol (sulfuric acid), and cotton (and distilled water to rinse it off).

[Jinumon]

Thanks Varyon. This sounds like exactly what I need. And the processes of producing nitric and sulfuric acid to create the final product should make it a complex enough recipe to prevent it from being stumbled upon by other nations.

To Bruno: I'm not particularly worried about the innovative steps involved, but rather whether or not it is physically conceivable using Low-Tech equipment, etc. So long as their laboratories can be created using the materials and practices of the day, I'm willing to overlook the marvelous invention with the placement of a few genius chemists or a religious significance that promotes chemistry.

Jinumon

[Anthony]

Originally Posted by Jinumon

As a simple question to any chemists or chemistry enthusiasts out there: Is it conceivable for a TL3+1 society to produce Nitroglycerin?

In small quantities mixed with various contaminants, probably. At a purity sufficient for practical use, probably not.

[Bruno]

The benefit of black powder is that the raw materials are available in the environment with minimal processing. Sulphur is a naturally found mineral, charcoal is sightly fussy to make but it's a one step process and the raw material is abundant, and saltpeter can be isolated from animal waste and human waste in a similarly simple process.

Cellulose can be naturally sourced, and some plant sources only need simple cleaning. Nitric acid was known by the 13th century, but the trick is getting it pure and concentrated enough for the reaction; that is more than a single secret - that's an important part of TL 5 chemistry.

[Bruno]

Nitric acid for the production of explosives is generally 90% pure. That is a very high standard, which until the 1910-1920s was done with very large amounts of electricity.

I'm not sure that can be achieved with 13th century knowledge and equipment. The more of this equipment you make available, the more this is a TL5 (or TL3+2 or whatever) society instead of TL 4 with a good trick.

Edit: to be clear, you cannot concentrate it beyond 68% with distillation. That's a huge problem.

[Bruno]

You can dry out the acid with oil of vitriol and then distill that to get higher percentage purity, but then you need to make significant quantities and volumes of that.

Modern processes for these acids require metals that are quite out of reach of TL 4 - platinum, palladium, rhodium - and high temperatures and pressures that again aren't TL4.

Now, this changes if you have magic. Create Acid for instance removes these issues.

[Ulzgoroth]

Originally Posted by Bruno

You can dry out the acid with oil of vitriol and then distill that to get higher percentage purity, but then you need to make significant quantities and volumes of that.

That makes things expensive (and is the reason that mass production of sulfuric acid is a somewhat under-hyped lynchpin of industrialization), but not impossible since you can make however much sulfuric acid you need in small tabletop batches, right?

[Bruno]

Originally Posted by Ulzgoroth

That makes things expensive (and is the reason that mass production of sulfuric acid is a somewhat under-hyped lynchpin of industrialization), but not impossible since you can make however much sulfuric acid you need in small tabletop batches, right?

That's true. I'm not sure it's enough volume to make it an Empire-founding secret weapon. Definitely easier to keep as a secret than black powder. If black powder is unknown, then it's useful as a secret weapon for seiges - tunneling is used even without explosives, but explosions make them much more effective. Petards would also be a nasty shock.

If black powder is known, it's not as radical.

[Anthony]

Originally Posted by Ulzgoroth

That makes things expensive (and is the reason that mass production of sulfuric acid is a somewhat under-hyped lynchpin of industrialization), but not impossible since you can make however much sulfuric acid you need in small tabletop batches, right?

You're still likely going to have issues with purity, which will make your explosives less stable -- and neither nitroglycerine nor nitrocellulose is really all that stable to start with.