| Pages:
1
2 |
chloric1
International Hazard
Posts: 1224
Registered: 8-10-2003
Location: GroupVII of the periodic table
Member Is Offline
Mood: Stoichiometrically Balanced
|
|
Quote: Originally posted by Fantasma4500  | i had some distillation mixture of H2SO4 and CaSO4 standing around
i dumped it into a plastic bottle to be situated next to my toilet, to help remove calcium deposits every now and then
about a year later i found the bottle again
and there was about a fist-sized chunk of crystals in there
i eventually found out it was CaSO4 crystals
https://gyazo.com/74e95b60263131dfad29986ace145977
now what i understand is that i hit a particular H2SO4 concentration in which CaSO4 is soluble in
and upon diluting this further, it precipitated out the CaSO4, very slowly
so there must be maybe 10-20% "sweetspot" with H2SO4/H2O concentration in which CaSO4 is soluble.
so that might work for ya.
i would say maybe 20% or even less is where the CaSO4 dissolve- its only a vague guess |
.
I’ve gotten gypsum crystals many times larger than precipitated calcium sulfate from concentrated ammonium nitrate solution. Easily filtered with
coffee filter! Calcium sulfate does have considerable solubility in ammonium salt solutions at room temperature. But a nice trick is that calcium
sulfate solubility is diminished by higher temperatures as well as increasing ammonium salt concentration. So if you make ammonium nitrate or
chloride by double displacement with calcium sulfate as the precipitated solid, know that boiling down ammonium salt filtrate with a couple gravity
filtrations will reduce dissolved calcium sulfate to less than 1% concentration before you get a salt cake.
Fellow molecular manipulator
|
|
|
Random
International Hazard
Posts: 1120
Registered: 7-5-2010
Location: In ur closet
Member Is Offline
Mood: Energetic
|
|
There was this procedure, was it inside Wagner Chemical Technology book from 1800s
...
Something regarding Sulfuric acid or Nitric acid... or \\\both
...
It was a procedure something as if you put all this inside a how we could call it vessel and let it burn or what was it...
...
I cannot recall it from my head currently.
Also I have seen this reaction how CaSO4 along with SiO2 gives SO3 when heated
...
They change this reaction into another with no SO3
Look what Politics is.
...
But let me get again how I could say OnTopic.
I could write a lot regarding this topic. But if I only quickly read it, don't use GlassWare then.
You can use another \\\material
Edit:
Metal. Ceramic.
...
Edit2:
What about Silver Nitrate and HCl
...
[Edited on 30-9-2024 by Random]
|
|
|
RogueRose
International Hazard
Posts: 1600
Registered: 16-6-2014
Member Is Offline
|
|
I found a convenient source for "disposable" glassware is to use old metal halide (HPS/MH) light bulbs (250w - 1500w) which I've found to be made of
borosilicate glass. The 1500w bulbs are 1.5-2.5L in size. I used a Dremel like tool with a diamond cutting disc to cut the glass near the bulb
thread & remove the "guts" of the bulb.
These bulbs are used in industrial applications like large parking lots, warehouses or any other place that needs large areas lighted. I found tons
of these (and the transformers) at various second hand building material stores (like Habitat for Humanity Re-Store & some Goodwill's). Many
places are replacing these lights with LED so these stores often have lots of these lights & bulbs.
|
|
|
Random
International Hazard
Posts: 1120
Registered: 7-5-2010
Location: In ur closet
Member Is Offline
Mood: Energetic
|
|
| Quote: Originally posted by RogueRose | I found a convenient source for "disposable" glassware is to use old metal halide (HPS/MH) light bulbs (250w - 1500w) which I've found to be made of
borosilicate glass. The 1500w bulbs are 1.5-2.5L in size. I used a Dremel like tool with a diamond cutting disc to cut the glass near the bulb
thread & remove the "guts" of the bulb.
These bulbs are used in industrial applications like large parking lots, warehouses or any other place that needs large areas lighted. I found tons
of these (and the transformers) at various second hand building material stores (like Habitat for Humanity Re-Store & some Goodwill's). Many
places are replacing these lights with LED so these stores often have lots of these lights & bulbs. |
There are various ideas what could be used as Apparatus.
I have been doing Plumbing before I started attending College and everything concerning dealing with Apparatus became easier for me.
|
|
|
jackchem2001
Hazard to Self
Posts: 99
Registered: 2-6-2024
Member Is Offline
|
|
Very interesting, good to know. Could the cracking instead be due to a crust forming with a different coefficient of thermal expansion rather than
direct embrittlement of the glass?
|
|
|
bnull
National Hazard
Posts: 842
Registered: 15-1-2024
Location: East Woods
Member Is Offline
Mood: preparing copper salts and enjoying it
|
|
| Quote: | | Could the cracking instead be due to a crust forming with a different coefficient of thermal expansion rather than direct embrittlement of the glass?
|
No, it's really embrittlement. I found at least one paper describing the effects of substitution or removal of sodium from glass. If I'm not mistaken,
it was N. J. Kreidl, B. F. Trumm, R. F. Scott, Electrolytical Replacement of Sodium by Ammonium in Glass (https://doi.org/10.1111/j.1151-2916.1941.tb14850.x). From the abstract:
| Quote: | | A review is given of the exchange of ions (1) in glasses containing water, (2) on the hydrated surfaces of ordinary glasses, and (3) in commercial
glasses with and without the application of an electrical field, and it is shown that the ammonium ion offers unique features. It may be
electrolytically introduced into soda glasses without impairing their structure as much as other ions. |
|
|
|
jackchem2001
Hazard to Self
Posts: 99
Registered: 2-6-2024
Member Is Offline
|
|
Does this calcium embrittlement effect only happen with very particular conditions? I had a 100mL RBF I never used so wanted to destroy it while
getting some use out of it. So what I did was to take ~50mL of dry CaSO3 + KNO3 powdered mixture and slowly heat to roughly ~500-580 degrees celcius
using a blow torch (as measured by an IR thermometer as the wall temperature) to give CaSO4 + KNO2. The heating was done slowly and evenly and was
held for ~10 minutes once temperature was reached. Afterwards, no attempt was made to slowly cool the vessel (free convection air cooling).
Note that I did this at least 5 times and yet the vessel shows no sign of deformation/defect. To recover the reaction mixture, each time I had to add
water and stab/scrap at it quite hard with a moderately hard plastic rod. The temperature is well above the working temperature of borosillicate (and
indeed above users who have reported calcium embrittlement) and actually into annealing region. And yet despite all this the vessel seems fine and was
perfectly cleaned by a little HCl.
I will keep the vessel for curiosity but will never use it again.
My only idea why it survived is that there was no molten salts/liquid in the reaction (even though the reaction is above the m.p. of KNO3, it just
sinters and isn't seen to melt)
|
|
|
clearly_not_atara
International Hazard
Posts: 2905
Registered: 3-11-2013
Member Is Offline
Mood: Big
|
|
| Quote: Originally posted by Amos | | Quote: Originally posted by clearly_not_atara | If you want to do a dry distillation, you can probably protect your glassware by using a eutectic mixture of sodium and potassium bisulfate instead of
just one or the other.
Eutectic (44% KHSO4 by moles; 50% by mass): 133 C [1]
NaHSO4: 315 C [2]
KHSO4: 197 C [2]
|
If the reaction is successful though, bisulfates will still end up as solid sulfates |
The goal here is to lower the rxn temperature, because ions will diffuse into glass (embrittlement) faster at high temperatures.
Solid, cool CaSO4 on glassware can probably be removed by using citric acid, which chelates calcium.
|
|
|
| Pages:
1
2 |
![[*]](images/xpblue/default_icon.gif){kind=icon}
