What I mean by 'shake and bake', is basically chucking in a layer of a nonpolar solvent, and at the bottom, a mix of strong base and ammonium salt, to form a bilayer in a pop bottle, along with the pseudo/ephedrine in the nonpolar, and the ammonia generated by means of the stronger base (usually something like caustic soda, NaOH/sodium hydroxide) displacing the weaker base, NH3, ammonia, to replace the cation, say if one started with ammonium sulfate and sodium hydroxide, one would get ammonia and sodium sulfate (ammonium hydroxide is a bit of a misnomer, it is often referred to as such, but in aqueous solution it doesn't form to any great extent as an actual molecular species) anyhow, that is what happens, strong base kicks out the weaker base and forms the corresponding salt, liberating the weaker base.
This in an ammonium salt, means ammonia liberation. H2O is added, as I understand the process, in a very small amount to get it to proceed.
And this horror, with the suspended Li bits, is then stuck in a capped plastic bottle, which the crazy buggers that do it have to periodically 'fart', I.e release part of the building up pressure. Otherwise the pressure makes the whole thing explode due to overpressure, spraying caustic alkali everywhere, filling the place with ammonia, flammable nonpolar fuel, such as ether, along with an alkali metal which has a chance to cause the fuel vapor to ignite.
Basically, shake and bake is a redneck way of rigging up a bomb that they hope won't actually blow up in their face, and that includes pseudoephedrine as a filling. In the hopes that, assuming it doesn't explode and cover the poor sod in 3rd degree burns and pepper them with hot corrosives, they might then extract the meth from the nonpolar after addition of a proton donor, an alcohol, to allow the reaction to finish, and assist in quenching it, as the wastes are dangerously water-reactive, such as lithium amide. Alkali metal amides are water sensitive and quite violently reactive in such a case, get very hot very quickly and blast ammonia from here to the gates 'o'hell.
It's a really, really ghetto-ed version of a legitimate technique of reduction of pseudoephedrine/ephedrine to methamphetamine known as a Birch-Benkeser reduction.
In the case of PSE/ephedrine then it's an unusual application. Usually the B-B reduction reduces a phenyl (benzene) ring to a cyclohexadiene, or else is employed to entirely de-aromatize an aromatic ring, such as full reduction of benzene to cyclohexane. Lithium being the more aggressive, but less physically violent, compared to sodium, whilst Na, sodium, is MUCH more liable to ignite, if things go tits up, than lithium is. Li can be pretty calm, in terms of spontaneous fire, I've even held a slice of lithium metal in tongs, run it under the kitchen tap (not making meth at the time), and then even dunked it into a pan of water and held it there, as well as allowed it to surface.
It fizzed, it shot around the surface of the water, on it's cloud of evolved hydrogen gas, it ran around the place like a squirrel on a crack bender, but never did it actually take flame or spark. Nor ignite the H2 evolved. I TRIED to get it to do so, tried pretty hard with several pieces of lithium, why? for fun basically
But no success in that respect.
A little piece of sodium about the size of a BB pellet on the other hand, chuck that in water and you'll almost certainly get at least a spark, a pop and an orange flame (from the sodium D line in the visual spectrum of it's emissions, just like street lights). That could ignite the hydrogen, easily, and then that would probably take the flammable nonpolar solvent with it, result of the botched shake and bake? boom! ARRGGHWHERESMYFACE!'
And a bigger bit of sodium, it can be downright violent. Say, a one inch cubed size specimen, if that were tossed into H2O then it WOULD go off with a loud crack and shoot off in flames.
Bits around 1cm....especially if they heat up enough to become molten in reaction with the water, then when molten its another beastie entirely, take one of my past electrolytic cells, running on NaOH (caustic soda, molten, heated electrically, water-free of course), once had an argon tank run dry, that was being used as a protective inert atmosphere.
I got cut off from the lab power supply, because the cell was interposed between it, and the wall socket, so I couldn't cut the power, even wearing a blast shield, little blobs, between BB size and at largest single blob, about 1.5-2cm, were forming and immediately reacting with the air, to a sound like machinegun fire rate-wise, constant stream of crackling, popping loud bangs, every so often, interspersed with a single, or a couple of loud sharp reports, as a big blob of molten Na coalesced together before exploding in a flying ball of bright orange dripping flaming metal.
Even with thick gloves, goggles and a blast shield over the top covering from forehead to torso, thick leather trench over my body, I couldn't even get close, I had to leg it in the opposite direction and kill the power supply at the source, turning the house mains supply off at the fuse box.
Quite a fun 4-5 AM little excursion into incidental pyrotechnics, and to me, in that circumstance, most amusing.
But had that been in a bottle of ether, it'd have blown up in a seriously dangerous way. Especially pressurized, full of caustic alkali, full of pressurized ammonia gas, and dependent upon the reactions of the person conducting such a procedure being fast enough in judging exactly when to 'burp' the bottle and stop it exploding in their face....another matter altogether.
Thats the kind of worst case scenario in a shake and bake. Third degree burns, an explosion, alkali metal serving as shrapnel, whilst molten and exploding in wound cavities (not fun, I once got a bit up my nose as a teen, in some initial clumsy attempts at molten caustic electrolysis. A bit of sodium went 'WHUMP!', shot off through the air, and right up my right nostril, before going off again, on meeting all that wetness generally found inside a human nose. Of course, I was wearing goggles, but one generally doesn't think 'hm, maybe I should have stuffed bog roll, tampons, or both, up each nostril whilst presiding over a spitting, crackling electrolytic cell.
Eyes, first thing, but up the nose?
(and no, for the record, I didn't use tampons, I used bog roll, wadded up and stuffed up my hooter to prevent any further inadvertent insufflation of molten sodium and any more than the one little crater blasted into my nasal septum, like a male daniella westbrook, but far better looking, but with the nasal trauma condensed into a matter of seconds
)