thanks poisoninthestain, so it's unlikely swim's hgcl2 is decomposed then.  he was assuming it had either a) decomposed somewhat or b) was contaminated with other salts to some degree.

is there any way to test the purity of hgcl2? of course you can run a test amalgam but for someone who's never run the al/hg reduction before it's hard to tell just how "on point" the amalgamation is going. it's important to know the purity of the hgcl2 so you don't get a dead al/hg or a volcano.

for example swim had a dream where he tested a little bit of hgcl2 in MeOH with a couple balls of al. it took a long time, several hours probably, but it eventually melted the al down to goop. one would imagine that a test of this nature without any additional reactions happening to cause an exothermic reaction, that the amalgam would indeed take several hours to complete so swim supposes this is ok.

but swim is worried about the purity of hgcl2 because it only partially dissolves in MeOH and h2o, signaling the presence of contaminant salts unless hgcl2 isn't quite as soluble as it's reputation makes it seem. most of his hgcl2 dissolves, especially in ethanol which is weird that it didn't dissolve as quickly in methanol. anyway, he'd rather just scale up the contaminated hgcl2 to meet the required amount of pure hgcl2 rather than recrystallize it, he's quite tired of dealing with this nasty stuff in dreams.

here's a procedure of something he read about online to help identify possible contaminant salts or whether or not some of the salts were indeed decomposed, yields seem a bit too high so he's wondering about contaminants:


day 1:
added 20g elemental Hg to a 500ml flat bottom flask
added 60ml h2so4 to the same flask
cranked up high heat and put a stirbar on medium
soon as heat the picked up, noticed vigorous bubbles (boiling) of so2 formation, loads of so2 fumes pouring out of the flask
the solution progressed to yellow, then orange, then brown
at the end of the first hour, noticed particles in the solution, backed off the heat just a little bit
at the 3 hour mark, noticed solution was still fuming but much less than earlier.  turned off heat and turned off stirbar
the solution was clear and orange/brown, dangerous but absolutely beautiful bright white crystals encrusted all over the upper part of the flask's neck, think the stirring was a bad idea or perhaps too much heat.  the bubbles/stirring probably projected the precipitated crystals up along the inside of the flask.  there is even some crystals on the hotplate and clamp, swim hates working with this stuff
stopped for the day, sealed the flask with plastic wrap and put it in the dark


day 4:
added 166ml brine solution to the HgSO4, at first added a couple drops and it reacted exothermically due to the remaining h2so4.  however there was not much h2so4 left (pipetted off most of it) so it only got exothermic enough to dissolve some of the hgso4
put the flat bottom flask back on the hotplate with stirring set to low, set the heat to about 70-80C and eventually all the hgso4 dissolved in the brine solution.  no yellow precipitate was noticed
turned off the heat and let it cool off
added 100ml saturated NaOH solution, brilliant flashes of bright orange appeared briefly as the NaOH was added
added another 200ml saturated NaOH solution, more flashes of bright orange appeared, the aqueous solution began to turn yellow then orange as yellow/orange precipitate fell out of the solution.  could have added another 100-200ml saturated NaOH solution until aqueous layer turned brown to make sure all HgO has precipitated however the flask is almost full and don't want to use any more flasks for this hideous stuff, so will just take the loss
gave the HgO time to settle at the bottom, then decanted the orange aqueous solution
the remaining precipitated HgO was washed 2x with 200ml dh2o and decanted to help remove NaCl and NaOH from the brine and NaOH solutions used.  a little HgO was sacrificed because swim wanted to decant as much water off each time as possible to get rid of contaminant salts, both times the HgO was allowed to settle before decanting the dh2o
added 366ml dh2o (enough for the HgCl2 to dissolve in after formation)
added hcl solution (100ml dh2o + 20ml 33% hcl) dropwise until the solution turned colorless (and cloudy from precipitate - not enough water to dissolve all the HgCl2?)
stopped for the day and put the flask in the dark


day 5:
noticed some white precipitate on the bottom of the flask and the water was clear, added more dh2o in hopes that this precipitate would dissolve in it, assuming it is HgCl2
upon addition of extra dh2o the solution became cloudy again but it looked like most of it did dissolve
poured the solution into a glass dish (never to be used for consumables ever again) on a hotplate with the heat set to about 80C
over the course of about 5-6 hours the water evaporated and left a white powder, many needle-like crystals on the sides and a big pile of powder in the center where the water collected before it was dissolved entirely <- this is where the apparent sublimation occurred as stated in previous post and the salts became very compact and caked together
salts were scraped up to yield 19.76g

test amalgam #1:
a mason jar was filled with 50ml tap water, a little bit of HgCl2 was added to the water.  most of it dissolved but some did not, added 2 balls of aluminum foil
checked back 15 minutes later and nothing has changed, some HgCl2 still sitting on the bottom undissolved but not much, some 95% EtOH was added to help solubility
checked back 20 minutes later and the aluminum foil balls were flattened (melted) and sizzling a little bit
checked back a couple hours later and saw a gray solution with no undissolved aluminum foil

test amalgam #2:
a mason jar was filled with 30ml anhydrous MeOH, a little bit of HgCl2 (2 knife tips worth) was added to the MeOH, some dissolved but most just sat, clumped on the bottom of the jar.  some agitation and stirred helped dissolve some of it but still all did not dissolve.  added a couple heavy duty al foil balls
checked back 30 minutes later and some of the coating of the al had been eaten away to show a darker gray area of the al but still a great deal of the AlO coating was present
checked back another 30 minutes later and not much else changed, al looked a little more flattened
added a couple drops of nitromethane to see if it would heat up at all, it did absolutely nothing
checked back the next day and the mason jar had nothing more than an obliterated pile of al goo, broken down al foil saturated in MeOH most likely
swim thinks he used too little solvent but it was enough to completely cover all the al foil (before it was amalgamated) but still thinks there was just too much al foil and too little solvent

There has been some talk in the past at the hive about doing it this way but I have to admit im a bit skeptical due to passification of the Hg.

I recently heard of a means of performing the amalgum quick and dirty thru the use of HCl/(M)nitrate/Hg. This should break any passification that may form thru the use of modifyed aqua regia and generate Hg(NO2)2. This salt is by far the best for the formation of amalgums due to its solubility and the best of all no fucking with a total synthesis of Hg compounds.

I have about 20 grams of Hg sitting around and am thinking of producing a write up about the formation of the amalgum using these means but I dont want to waste my Hg so im on the fence at the moment.

ah, can't distill?

I have prepared soluble Hg (II) in situ using hydrochloric acid and ammonium nitrate. Polverone posted about it over at SM I think. I did a test tube experiment -- one drop (0.5 g?) of mercury, covered with hardware store HCl, added 4-5 prills of NH4NO3 from a cold pack. Let it set in a warm spot and it dissolved completely overnight. Slightly yellow-green solution was formed, color cleared on prolonged standing.

When I dripped it into aqueous solution it rapidly amalgamated copper sheet, zinc shot, and aluminum foil. The excess acid probably helps that along by removing oxides from substrate metals. I doubt the small remaining amounts of nitrate and ammonium ions will affect typical amalgam uses. If you want to be completely sure it's non-oxidizing, I'd let it sit a long time with excess mercury and HCl (short it on the nitrate) before decanting the aqueous part.

I only tried it once myself because I already have more lab grade HgCl2 than I'd use in 5 years. One nice thing about this method is that the Hg(II) is completely dissolved from the start. My bought HgCl2 is in slightly coarse crystals that take time to dissolve in water and initially just want to float on top of it.

It seems like H2O2 and HCl might give an even cleaner product but in practice I wasn't able to get the mix to attack mercury. Might work better if you use fairly conc. H2O2 and warm it a bit so some free chlorine is formed; I was just using the 3% disinfectant.

I used 65% HNO3 and Hg metal to get greenish tranasparent solution.
Evaporated liquid,torched solid and reacted it with HCl,evaporated liquid again.
Ended up with white solid that is very soluble in pure MeOH.

I believeit's mostly HgCl2 with some Hg(NO3)2 but I don't give a damn since
it works like a charm for Al/Hg red. amination!

Now I found bottle full of pure HgCl2 and I am happy since that means no more
playing with Hg salts for me!

The solution can be used, I have read many examples of it working. You do not need specifically HgCl2, after dissolving the metal in HNO3 it will work for amalgamation.
Also, no toxic fumes? I once dissolved mercury in nitric acid and it made quite a bit of NO2.

Yes I agree it's a bad thing, and if someones goal is to amalgamate Al which is usually the case there is no need to purchase HgCl2, which is watched. You can make nitric acid so easy, or just buy it. Mercury is easily obtainable. I do not see why anyone wouldn't just use these! Is it because people think it might not work?

IT WORKS

This is all i have to say, what else is there to say. Sometimes I feel people overcomplicate things.

You can read some text that was scanned and OCR'd from Mellors:

https://the-collective.ws/forum/index.php?topic=20083

there may be more information on the internet but that will take time to locate 

So I had this dream where I was attempting to make HgCl2.  In the dream I boiled 7g Hg in 45ml conc.sulphuric acid.  I left it overnight and returned to find lovely white (ish) crystals.  Proceeded to add sat. brine solution, and could not get any of the mud to dissolve with stitting and/or crunching.  In the dream I kept the sludge in hopes that I could recover my precious Hg.  Then I woke up without a solution.  Anyone got any help for me?   I really like the idea about HNO3.  Could I add nitric to my sludge?

HgSO4 to HgCl2.

Make up 500 ml saturated sodium(bi)carbonate solution. Add this to the HgSO4/acid solution in small quantities until effervescence upon addition stops and a red-brown precipitate forms. Filter off the precipitate. Add some more (bi)carbonate solution to the filtrate to ensure all the HgSO4 has been reacted. Filter and repeat until no more red-brown precipitate forms. Wash precipitate with DH2O. Place in a 500 ml beaker and create a suspension with 20 ml DH2O. Make up a solution of 20 ml strong hydrochloric acid in 100 ml DH2O. Add this to the suspension in small quantities with good stirring. The solution will change from brown-red to yellow and finally a white curdy precipitate will be present in the liquid. Stop addition of the HCl when the white precipitate appears. It is important that the solution pH should be near neutral as excess hydrochloric acid will prevent the HgCl2 crystallising in the next stage. Evaporate off most of the water either outside or fit a single hole stopper with a tube leading outside to vent the steam away. Cool, filter the HgCl2 and dry. Yield 19.37g white crystals. For greater purity recrystallise from boiling DH2O.

Ref: http://www.scientistsolutions.com/t1060-hgcl2+preparation+and+storage.html

The method I used was from rhodium archive (I believe the author was zygoat), and when I got to the part of adding hot water to the HgSO4 to dissolve it (another trusted member from another forum suggested sat. brine solution), it would not dissolve.  Turned into a silt/mud like sludge.  Proceeded to add bicarbonate, and got some effervescence (probably due to leftover H2SO4), but still had mud.  Addition of bicarb was exothermic and the flask got hot so I continued to add, but no colorchange occured, and it seemed that my pile of sludge was just getting bigger.  So I took a small amount and placed it in a test tube and added some HCl solution, and no color change happened. So I gave up and put all of my HgSO4/sludge/water/bicarb/HCl junk into a sealed HDPE container And the dream ended.  I'm assuming that in future dreams I should aquire more mercury, but wish there was a way to salvage something from the crap.