Lets say you plan to do 15 grams of E (dry E) so you
put it in a in a 1 liter flask ,
you decide you want a extremely fast reaction,
Add 1.5 x I2 or 22.5 grams of I2 (dry I2). That is an excess and will insure plenty of I2.
Add 0.8 x Rp or 12 grams (dry RP) This excess amount of RP will insure
that PI3 and I- are available very rapidly to the reaction as it is needed.
Mix it together and it sits there.
Tape on a stopper with an attached
fume hose and inject 4 mls of water into the hose so it drips into the reaction
flask , shake it up and 'viola' a spontaneous reaction , no heat is added , the
reaxtion is very strong bubbling seething producing gas.
Shake it and chill it obtaining a general control and slowing the reaction,
A little heat is added and the reaction fires off hard turning darker and
turbulant, within 30 seconds the redness seems to vanish the reaction slows and
the walls of the flask become clear/
Add another blast of heat and inject another 2 ml of water, the reaction bubbles and fizzes slightly indicating it is basically dead, the whole reaction took place in 5-10 minutes and produced 10 grams of some excellent speed.
Had 10-15 ml of water been added before the RP, the reaction would not
fire spontaneously.
but you could reflux it for several hours and it would
eventually turn ,
you could lightly boil it in an open flask releasing water
and HI until it thickened 1-2 hours and you would have meth
the reaction mechanism is the same.
Individual steps
---------------
P4 + 6 I2 -> 4 PI3
4PI3 +4 I2
->4 PI5
4PI5 + 16 H2O -> 4 H3PO4 + 20 HI
10 E-OH + 20 HI <-> 10 E-I + 10 H2O + 10 H I
10 E-I +
10 HI -->> 10 M-H + 10 I2
Overall reaction
------------------
P4 + 10 I2 + 16 H20 + 10
E-OH --> 10 M-H + 10 I2 + 4 H3PO4 + 10 H20
not
that simple is it
Where
P4 = red phosphorous
I2 = crystal iodine
E-OH=
ephedrine
E-I = iodated Ephedrine or iodated pre meth
M-H=
methamphet.
Water is used up
P4 is turned into phosphate and lost
Iodine is
restored (the actual catalyst) except it is part of the reaction.
What can be said about what promotes and what retards the reaction
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More P4 creates more HI
More HI pushes the reaction to the right
P4
absorbs water pushing the reaction to the right
So the Phos uses whatever water it can
find to make HI from I2
And
pushes the reaction to completion.
So What??
Who cares about that stuff ?
To get the reaction to fail do this:
-----------------------------------
Too much water, or too little water
Too little Phos
Too little HI or
I2
A sucessful reaction has this:
--------------------------------
Just
the right amount of water
Slight excess of Iodine
Lots of Phosphorus
For those who wish to exercise control over the rate of the reaction:
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The rate of the reaction can be controled by the amount of water it is
supplied. By adding water a little at a time, the reaction rate can be increased
or decreased
or by
The amount of Phosphorous added
or by the
amount of iodine added
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