Hey Buddy
Hazard to Others
Posts: 441
Registered: 3-11-2020
Location: Bushwhacker Country
Member Is Offline
|
|
Hi. Im new here.
What step order do you take when presented with two substances in an industrial mixture.-- to figure out how to separate them?
The specific circumstance is NaOH/NaNO3 buckets from a lagoon plant. It's a couple hundred kilos. Someone suggested to convert the hydroxide to
nitrate and deal with the mixture in that way, but is separation possible? Or are they too close to separate? there must be individual procedures ppl
use to analyze components in a mixture to determine if separation is feasible. How do you analyze mixtures for separation?
One more, since I've got your eye balls here; synthesis of glyoxal: what is a "sweeping gas", in terms of, what does a sweeping gas operation "look
like" physically? How is gas "swept" through something else?
|
|
|
Hey Buddy
Hazard to Others
Posts: 441
Registered: 3-11-2020
Location: Bushwhacker Country
Member Is Offline
|
|
well, at least slap my ass. Or something
|
|
|
zed
International Hazard
Posts: 2284
Registered: 6-9-2008
Location: Great State of Jefferson, City of Portland
Member Is Offline
Mood: Semi-repentant Sith Lord
|
|
Converting NaOH to NaNO3, isn't practical. The easiest means to do so, would be by utilizing Nitric Acid.
Since Nitric Acid is more difficult to obtain, more expensive, and more desirable than NaNO3... You probably wouldn't do that.
Now, if you wanted to convert that mixture to Nitric Acid. That's not too hard.
Just treat the mixture with concentrated Sulfuric Acid, and distill off the Nitric acid, under reduced pressure, as it forms.
Depends on the percentage of NaNO3 to NaOH. Too much NaOH in the mix, and it becomes not worth it.
|
|
|
Fyndium
International Hazard
Posts: 1192
Registered: 12-7-2020
Location: Not in USA
Member Is Offline
|
|
Could you first neutralize the NaOH with something less valuable so it wouldn't consume more valuable sulfuric acid in the conversion process?
|
|
|
Tsjerk
International Hazard
Posts: 3032
Registered: 20-4-2005
Location: Netherlands
Member Is Offline
Mood: Mood
|
|
I think in the case of Hey Buddy "valuable" is a bit different from what many here would consider valuable, see his earlier posts.
Hey Buddy, what do you want to use the NaNO3 for? If it is to make nitric acid, you could just acidify the NaOH/NaNO3 mixture with sulfuric acid and
distill the nitric acid.
If you want NaNO3 without NaOH you could use the above formed nitric acid to acidify the NaOH/NaNO3 mixture.
If you want to get the NaOH, I don't really see any viable way.
[Edited on 8-11-2020 by Tsjerk]
|
|
|
Fyndium
International Hazard
Posts: 1192
Registered: 12-7-2020
Location: Not in USA
Member Is Offline
|
|
Ah, don't quite follow the energetics section. But valuable to me is anything that cannot be certainly bought OTC in pure or easily refined form in
bulk and cheap, and then it becomes a recoverable asset.
And more you do chemistry, the wider range of stuff you find use, hence today's trash is tomorrow's reagent. Been in that situation more than almost
every time I'm preparing something and realize I had that in my possession. For example, I had 2kg of sodium nitrite a decade ago, but I left them to
bad storage and I'm not exactly sure what happened, but they were practically molten into a mess and mixed with soil so they were total loss. Learned
from that, I take time to keep stuff in good packages, well labeled (so the labels won't wet or rot away) and in order.
But yep, the purpose of use states many times the method of process, and surprisingly many times stuff can be used as is, counting in the variables.
One scientific paper used otc laundry product as an oxidizer as is and it worked perfectly, even when it had significant amount of other stuff in it.
|
|
|
njl
National Hazard
Posts: 609
Registered: 26-11-2019
Location: under the sycamore tree
Member Is Offline
Mood: ambivalent
|
|
Would adding Calcium nitrate to the solution lower the hydroxide concentration via precipitation or would significant quantities of Calcium stay in
the water as Calcium nitrate?
|
|
|
Hey Buddy
Hazard to Others
Posts: 441
Registered: 3-11-2020
Location: Bushwhacker Country
Member Is Offline
|
|
Zed, this barney style explanation helps a lot. Thanks. Is there an order of precedence used when considering whether a mixture will separate or be
converted? Like for example, do you look at the compounds and think Mechanical
Separation>Solubility>Distillation>Electrolysis>Reaction/conversion?
I realized when I started thinking about this, it must be a common problem in-general for OTC supplies. Im guessing people that are skilled have
probably done that sort of thing so many times, they have a sort of mental analytical procedure for examining a mix for separation/conversion, then
take the matrix and select for either efficiency or a desirable product?
Tsjerk-- Thanks for the help. I think nitric acid makes the most sense. I'm literally just starting a lab as of last week and at this point I don't
know what I'm doing, but I'm studying intensively and motivated so at some point hopefully my questions make sense. An old municipal facility had a
room full of absndoned chemicals they haven't used in at least a decade. I cleared out what seemed useful, both the caustic oxidizer mix, a ton of
H2SO4, unidentified petroleum distillate, some hydrochloric (a gallon leaked in truck bed, leaving a rust layer, i neutralized with baking soda and
sprayed with hose). Anyways, the way my mind works I look at something like a mix such as (a+b) or an adulterated solution (a/b) and think, "these
must be separated into isolated stock for usefulness".
So I have no specific goal (other than building stock) just want to begin and learn more. It seems like I got really lucky with the drain cleaner and
if the caustic mix has high NaNO3 as a route to nitric, then im double lucky.
The other issue, "sweeping gas" as a procedure, in general; i can't find anything clear on this as to what the heck that means, most of what I find
from the term use is related to industrial application with catalysts. Is a "sweep gas" like a bubbling of a gas through a fluid bottom to top (like
aeration)? Or is sweep gas operation like a push gas into a flask and back out in the volume above the fluid reaction to exchange and sweep the gasses
in that space?
Sorry for long form. Having a hard time finding clear explanation.
|
|
|
Texium
Administrator
Posts: 4619
Registered: 11-1-2014
Location: Salt Lake City
Member Is Online
Mood: PhD candidate!
|
|
Quote: Originally posted by Hey Buddy  | | Zed, this barney style explanation helps a lot. Thanks. Is there an order of precedence used when considering whether a mixture will separate or be
converted? Like for example, do you look at the compounds and think Mechanical
Separation>Solubility>Distillation>Electrolysis>Reaction/conversion? |
Yes, you’ve got the
order of preference pretty much down. Looking at it step by step:
Mechanical separation: not possible, because NaOH and NaNO3 are both white powders that would be intimately mixed.
Solubility: not possible because both substances are highly soluble
Distillation: not possible because both substances are non-volatile
Electrolysis: this really would be a subset of reaction/conversion and isn’t applicable to this scenario
Reaction/conversion: there isn’t a feasible way to recover NaOH from the mixture, but conversion to pure sodium nitrate with nitric acid, or
conversion of the mixture to sodium sulfate and nitric acid with sulfuric acid is feasible.
I would suggest doing a rough titration of your mixture with a standard acid solution so that you can know for sure whether it’s mostly nitrate or
mostly hydroxide. In lieu of a titration, you could also just get some pH paper, and determine the pH of a certain mass of the mixture dissolved into
a liter of water to get a rough idea of how much NaOH is in there. It sounds like you have tons of sulfuric acid on hand though, so I would expect the
nitric acid procedure to be practical for you regardless of what the composition is.
As for the “sweeping gas” procedure, I’ve never heard of it. Sounds like one of those industrial process that would require industrial equipment
and not something that would be feasible in an amateur lab unless someone went to the trouble of fabricating a purpose-built micro-industrial setup.
|
|
|
Corrosive Joeseph
National Hazard
Posts: 915
Registered: 17-5-2015
Location: The Other Place
Member Is Offline
Mood: Cyclic
|
|
Pipe in gas from small tank (eg. CO2 or argon) while puling a gentle vacuum..... Sweeping gas..... Cheap and easy.
/CJ
Being well adjusted to a sick society is no measure of one's mental health
|
|
|
Hey Buddy
Hazard to Others
Posts: 441
Registered: 3-11-2020
Location: Bushwhacker Country
Member Is Offline
|
|
Is the piped in gas submerged in the reactants so that it bubbles through (like in aeration/carbonation) or is it just piped into the top of the
reactant vessel?
|
|
|
Fyndium
International Hazard
Posts: 1192
Registered: 12-7-2020
Location: Not in USA
Member Is Offline
|
|
Part of the nitrate could indeed be recovered by adding potassium carbonate (or chloride if no else) and crystallizing it out as KNO3. The sodium
should remain in as hydroxide or chloride and potassium as carbonate, if they do not counteract each one's solubilities. Recovery will be far from
100%, but at least large part can be recovered.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
