semiconductive
Hazard to Others
Posts: 287
Registered: 12-2-2017
Location: Scappoose Oregon, USA.
Member Is Offline
Mood: Explorative
|
|
Low denisty organic fluids for making immiscible bi-layers.
I've been doing electrochemistry (inorganic) for a number of years; and decided to try and see if I can electroplate aluminum by exlcusion of water
and air in an organic or semi-organic electrolyte.
I've gotten to the point where I can get aluminum to electroplate, but only for a short while before the electrolytre breaks down. Several
electrolytes share the same basic issue; Eg: it appears that oxygen or something in the air chemically combines during deposition of aluminum on the
electrode and destroys the organic electrolyte.
Once that process begins, aluminum no longer electrplates and the electrolyte breaks down into sludge.
I've tried, for example, DMSO (Di-Methyl sulf-oxdide) and urea mixes with ascorbic acid as the active acid. I will get a thin coat of metallic
aluminum after about a day of electroplating to remove water, and then the electrolyte will begin to turn to sludge and the coating oxidize with no
further deposition. ( The oxygen in DMSO is also another problem.... I'm not sure how to get rid of it. Sulfur should be less of a problem. )
So, I began experimenting with immiscible oils as air excluders since they will float on top of DMSO and other ionic liquids.
However another problem cropped up during experiments ..
Many oils, such as silicone, are dense enough that they sink -- which defeats the purpose of having an oil film on top of the electrolyte (to
prevent/reduce moisture and oxgen from penetrating) I don't want the oil to sink, or the electrolyte to mix with the oil and get to the surface where
the air is.
The best oil I've found so far is plain orange oil ( I think it's, D - limonene) used for woodworking. It floats on most electrolytes I've tried,
and makes a decent air exclusion layer without being toxic/evaporating under heat -- or having high cost.
But It has a drawback. When using electrolytes made from de-hydroxygenating alocohols (Methanol, Isopropyl, for example can be mixed with ortho-boric
acid) and electroytically destroying the water in solution -- a point comes in the experiment where almost all the water is broken down and suddenly
the ionic liquid becomes miscible with the orange oil. It's actually a pretty rapid onset and mixing/dissolution once it begins.
I think what's happening is that as the alcohol combines with borates or other metals, etc. .The charged portion of the ion (the boron-oxygen,
alumnum-oxygen, Iron oxygen, portion ) becomes surrounded by a hydrocarbon layer; For example: B-[O-R]3 where R is methyl, isopropyl, etc.
Generally, a point comes in the experiment (right about where a thin impure metal film starts to visibly plate --- which is VERY frustrating) and
suddenly the orange oil on top miscs with the electrolyte and the two become in-seperable. It's easy to see because of the color difference of
orange oil, as the bi-layer separation disappears. This is especially true with Isopropyl alcohol being de-hydroxygenated.
I know some oils do not misc well even with each other, eg: silicone brake fluid will not mix with corn oil; and I've used that to remove the dye in
NAPA(TM) brake fluid as the dye prefers corn oil.
But, I am wondering if anyone has any ideas of other oils/waxes that are likely to float and act as an air exlusion layer on methyl borates, or other
organo-metalics; eg: What are the least "dense" liquids (non-polar, or very weakly polar) that I might be able to get cheaply, and which are of low
toxicity and cost?
Acetone, Mek, mix and don't float -- and worse, they give up their oxygen easily.
I've tried moth balls (napthalia), a few waxes, silicone oil, and solids all sink.
Essential oils, such as bitter almond, are almost always extracted with alcohols -- which means they will dissolve in a methylated or isopropylated
borate electrolyte.
I haven't found an online experimenters handbook which discusses the properties of oils relative to methyl groups in terms of density and reason
why/why certain oils/organic will mix or not.
What extra-low density oils / organic liquids would be worth trying ( I assume they will be longer chained chained so they don't misc well with short
chain alcohols such as Methanol or Isopropyl. Perhaps a flurocarbon ? )
Any thoughts?
Thanks!
[Edited on 19-3-2020 by semiconductive]
|
|
|
Deathunter88
National Hazard
Posts: 507
Registered: 20-2-2015
Location: Beijing, China
Member Is Offline
Mood: No Mood
|
|
Mineral oil?
|
|
|
DavidJR
National Hazard
Posts: 908
Registered: 1-1-2018
Location: Scotland
Member Is Offline
Mood: Tired
|
|
Maybe use inert gas instead?
|
|
|
DraconicAcid
International Hazard
Posts: 4278
Registered: 1-2-2013
Location: The tiniest college campus ever....
Member Is Offline
Mood: Semi-victorious.
|
|
Can you increase the density of the electrolyte by adding, say, a bromide?
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
|
|
|
clearly_not_atara
International Hazard
Posts: 2691
Registered: 3-11-2013
Member Is Offline
Mood: Big
|
|
Maybe just make your ionic layer heavier by adding some KOTf or something as an electrolyte? (KOTf in particular should be reasonably heavy and very
stable under the conditions).
Anyway, putting anything other than carbon in a liquid makes it heavier. That restricts your choices for organic liquids to alkanes and
alkanes. Aromatic compounds are also dense due to pi-stacking. On this basis I suggest using gasoline or cyclohexane. Cymenes may also work.
[Edited on 19-3-2020 by clearly_not_atara]
[Edited on 04-20-1969 by clearly_not_atara]
|
|
|
semiconductive
Hazard to Others
Posts: 287
Registered: 12-2-2017
Location: Scappoose Oregon, USA.
Member Is Offline
Mood: Explorative
|
|
Hmmm .... Those are some good thoughts..... Here's some notes and some questions:
Question #1: Cyclohexane ... is it dry, or easily dried by Calcium Chloride? Would I need to mail order it, or is it in fuels at local stores?
Alkanes, alkenes ...
Any cheap ones come to mind?
Alkaline metals .... I've tried adding sodium and potassium to the electrolyte. Sodium gets rid of hydrogen rapidly and makes an alkoxide out of
alcohol. So far so good ... but sodium alkoxides don't dissolve in methanol or methanol electrolyte, so the result is a white film forming on the the
carbon electrode (negative side) and the experiment stops after about an hour. Potassium salts ( Potassium Ferrocyanide, Potassium Chloride ) can be
used to force potassium alkoxides to form; the potassium salts don't stop the experiment from continuinig. But any chloride generally ruins the
experiment in the long run. I tried burning tartric acid from the grocery store to get potassium carbonate in the microwave. Wow. Works, but
smells.
Potassium does usually dissolve in the electrolyte, increasing it's conductivity and it's density; but there's only a limited amout of potassium
alkoxide that will dissolve; then the solution tends to go solid.
I've tried adding lithium carbonate and titanium oxide, to see if any complexes would form or help the electrolyte stay liquid. The entire solution
turned white, and stayed white; so one or the other probably forms a colloid? In any event, I got white stuff on the electrode -- So, I may try
that again with lithium carbonate alone; but it didn't *seem* to work. I'm out of iodine, and I using HCl would defeat the purpose of adding the
lithium.
Gasoline, (kerosine, or lamp oil), I suppose those are possible oleates that would float. But: Gasoline mixes with ethanol (alcohol), doesn't it?
So wouldn't gasoline likeley mix with methylated boron as soon as the water was electrolysed ?
This brings up that nagging question in my mind .....
Why do some oils not mix well with each other, besides being 'non-ionic' in nature.
Why doesn't vegetable oil mix with silicone oil even under heavy shaking -- there's some kind of molecular shape issue; and not the density alone for
I don't get "cloudy" solutions that clear -- they never go together. Density is one of the factors causing them to separate, but is it the only one?
I'm getting rid of oxygen, (i mean, the few bubbles that come out of the electrolyte aren't enough to sustain a burn. ) So, flammable sealants are
not a problem. I've got a24/40 glassware reflux tube over the electrolyte and it's sealed with 3M putty/mastic that Fred Meyers sells. The putty is
basically water tight/air tight ... but as it stretches it will leaks gasses slowly. So, basically when pressure builds up hydrogen and oxgen leak
out, but any warm methanol or borated methonal condenses on the tubes and flows back into the electrolyte. Reflux is good, and I loose very little
electrolyte. Should work for gasoline or kerosine.... unless they dissolve the putty.
I've tried density increasers ... e: If I add extra urea to the electrolye the density increases,; In that case even silicone oil can be made to
float; but things I can add to increase electrolyte density also tend to reduce it's conductivity significantly. For example, if small amounts of
pure silicone oil mixes with the electrolyte the current will go from a half ampere of current down to about 10 milli-amperes at 100Volts. (100x+
decrease in conductivity). A typcial (somewhat successful) experiment will use a quarter ampere of electricity, and 8CC's of electrolyte;, the
solution will usually bubble hydrogen and oxygen for 24 hours to a maximum of week before all the water (1% or less) is effectively removed from the
electrolyte.
But if I add silicone oil, conductiviy rapidly drops down to a few milli-amps even with 200V applied... At that smalll of a current, it would take
over a month to get to the anhydrous stage even if I could keep air totally out -- and I can't. eg: I can't even clean electrodes without opening the
apparatus. And where there's oxygen in trace amounts, I get metal oxide fouling of the negative electrode. (deposit side.)
The main enemies are free hydrogen (as it bubbles out -- gas -- hydrogen changes the conductivity of the solution/destabalizes it; but otherwise,
hydrogen is harmless), free oxygen -- it oxidizes metals -- and finally water because it supplies both of those gassifiable enemies when electricity
is present; Chlorine and Fluroine are also enemies (except in Chloroform electrolytes, which are promising but no alumium has yet plated... ) --eg:
Chlorine and Fluorine appear to be more aggressive than Oxygen and eat most organic electrolytes for lunch. DMSO turns to smoke with Chlorine... you
get brown metal (boron?) on the electrode which is not very conductive, and it's just as bad as the electrolyte being bad to have a poor electrode
conductor.
And worse ... Chlorine will still bubble out of solution faster than oxgen ... leaving the oxygen to attack any metal that *is* plated out. So with
respect to halogens, I'm basically limited to Bromine, Iodine, and below on the Periodic table.
I can get chlorox tablets for pools and make chloroform; but the bromide tablets include chlorine in them, so I don't think I can make bromoform.
The final enemy is miscibility, eg: even if the electrolyte is made "dense" -- if the oil or gas on top becomes soluble in the borated alcohol --
some (or a lot of it) inevitably mixes into the solution and the conductivity drops. Isopropyl alcohol will mix (in small amounts) with orange oil
even as an alcohol; But since isopropyl is denser than methanol, I've been able to get the experiments much farther along before the orange oil
mixes... still... the same problem eventually occurs. Ionization is decreased to the point where moisture wins the battle over electricity.
Inert gas is a possibility, but water traces in the electrolye are being lysed into oxygen and hydrogen; So, anything that stays on top as a gas will
end up keeping oxygen close to the surface unless it's MUCH denser than oxgen or it's flushed periodically. (More expensive gasses like Krypton might
work ... but even then, the oxygen has to be allowed to escape and some mechanism invented to keep the krypton close would be required. That makes
my brain hurt.... and don't feel like wasting money....) Right now, I'm counting on hydrogen produced by electrolysis flushing most the oxygen
out through an oil film and a thin putty plug which is barely air tight. Silicone caulk also works OK as a substitute for putty ... it balloons out,
and gases will leak through it as long as there's pressure; but silicone doesn't freely pass wet "air" into a slightly pressurized container. In
general, If I've got hydrogen coming out, then all (or almost all) Oxgen can be flushed out. (Eg: Hydrogen Iodide could be added to an electrolyte
to outgas hydrogen for a while, but the Iodine will stay in the ionic liquid. HOw to make anhydroud HI is the question ... I used up my iodine
trying.)
So, the best apparatus I've made to date is a graphite bottom electrode (-) in glassware; and I use refluxing tube on top so that any boiled
electrolyte goes back into solution after cooling down.
Back on the density idea ...
Some electrolytes are less misicible and more dense than others; Povodine from "betadine"(TM) iodine solution will not absorb the orange oil. So,
If I dehydrate betadine solution ... It (can) make a good electrolyte in some experiments; (It's main drawback is that it turns solid-gummy as water
is removed; and predictably conductivity goes WAAY down when things stop being liquid.) Povodine is not very promising for aluminum in my tests (so
far). the more aluminum I add - the faster povodine seems to solidify; However, when I use iron pyrite as an anode with povodine .... it curiously
increases in conductivity, rapidly. ; enough for me to electroplate grey cast iron without rust or black oxide layer after a long period of nothing
electroplating of anything. I was halfway hoping it would actually plate out as iron pyrite!!! ... cuz that's pretty. But, no -- just grey iron.
(no rust once the water is gone, it's not *"efficient"* but it works (and smells funny).)
However, I'm under the impression that aluminum sulfide isn't conductive of electricity so ... I haven't tried that route yet.
Attempts to electroplate aluminum from pure aluminum wire in the same povodine solution once iron and sulfur has made it conductive --- just continues
to plate iron. eg: Iron leaves solution before aluminum does. I don't think there's another metal that is both heavier than aluminum, and more
likely to stay in solution than aluminum. ( I was thinking I might dissolve lead or bismuth in there, but I'm pretty sure both of them would plate out
before aluminum would. )
Iron's actually a pain to electroplate too, as it reacts with oxygen and can be tri-valent. So, it's a good metal to try before aluminum as it shares
most of the same problems.
Inert gasses are a possibility .... I have a scuba tank that I've put dry ice inside of in the past. It usually leaks out throught the threads
within about a week .... and dry ice went way up in price this last year; So -- it's a fight between keeping the valve adjusted to flush oxygen, or
too open so that the tank empties out before the expeiment is finished. My thought about inert gases is that since oxygen is a gas that is released
from the solution when breaking down --- any trapped gas in contact with the electrolyte is going to slowly build up oxygen content. With dry ice --
I had to put cooked alumina poweder in the scuba tank as a dessicant to get traces of water out ... (Normal cheap CO2 liquid is NOT *dry*!!!!! ) and
then I let CO2 ice melt and flush all the air out of the tank ... But,that's only a halfway cheap solution. It still leaks and is used up within a
week.
Propane, butane, and other fuel hydocarbons I know of all have significant amounts of water in them.
Otherwise, I might try rosenol butane fuel ... but I'd have to find a way to keep it from leaking away.
On my wish list for someday is a hydrogen generator with a non-water electrolyte and separate hydrogen an oxgen outlets. Then I could use hydrogen
gas all day long to keep oxyten out of the experiments....
But -- Right now I'm using silicone sealant as a relatively inert way to make electrical seals; and still be somewhat air tight (not perfectly). The
only problem is that boron containing electrolytes eventually soften silicone and make it leak.
That brought up one last thought for an dense electrolyte ... maybe I could make/use silly putty as a dense liquid ike substance that is still
conductive ?
(Sometimes failures can lead to other successes.... )
|
|
|
Twospoons
International Hazard
Posts: 1280
Registered: 26-7-2004
Location: Middle Earth
Member Is Offline
Mood: A trace of hope...
|
|
After skimming that huge wall of text, I get the feeling that what might work for you is an inert dry gas bubbler at the bottom of your electrolyte.
The flow will carry away your unwanted compounds faster than diffusion from the surface, and you wont get the O2 buildup above your electrolyte.
If you are unsure of the water content of your inert gas it should be simple enough to dry it using a suitable dessicant or a cold trap (or both).
Helicopter: "helico" -> spiral, "pter" -> with wings
|
|
|
semiconductive
Hazard to Others
Posts: 287
Registered: 12-2-2017
Location: Scappoose Oregon, USA.
Member Is Offline
Mood: Explorative
|
|
Quote: Originally posted by clearly_not_atara  | Maybe just make your ionic layer heavier by adding some KOTf or something as an electrolyte? (KOTf in particular should be reasonably heavy and very
stable under the conditions).
Anyway, putting anything other than carbon in a liquid makes it heavier. That restricts your choices for organic liquids to alkanes and
alkanes. Aromatic compounds are also dense due to pi-stacking. On this basis I suggest using gasoline or cyclohexane. Cymenes may also work.
[Edited on 19-3-2020 by clearly_not_atara] |
I'm not familiar with the abbreviation, KOTf ....
Right, *Most* anything except hydrogen.... or carbon alone; So, Cyclohexane is 0.77g/ml but cyclopentane is 0.751g/ml -- both are less dense than
D-limonene, which is 0.841g/L and that's a density that floats (barely).
However, even pure carbon-graphite sinks. It Makes a good electrode, too. But the density of a molecule is controlled both by it's shape and it's
atoms. eg: Molecules that "Fit" well with each other, pack more densely than branched structures "sticking" out in random directions.
Ice is less dense than water because of shape-vibration interaction, and not atomic masses.
But -- with that in mind, recall that I'm using also using boron (element 5) in the ionic liquid.
Boron (itself) I think is lighter than carbon .... but boric acid is heavier because the oxygen adds mass... I have thought of messing with
beryllium to make an even lighter non-ionic fluid; but the cancer risks are too high.
Let me think:
Cymenes are very similar to D-limonine, correct?
From my memory that would be similar to Xylene, and Touloline?
I'm a bit wary of those (#3 in the health hazard chart) -- They definitely shorten people lives by attacking the CNS -- eg: Painters like several in
my family, and their friends all died much younger than the latex painters.
Is Cymene an exception -- I don't see an MSDS ?
Orange oil, and the Cyclohexanes and pentanes are in the '1' category for health; so I see those as similar to MEK and Acetone for health.
Hexane is $40/bottle US -- but I haven't found a source for pentane. It's expensive, but it's possible to stretch that much cash for a group of
experiments if nothing else will do.
Kerosine (Kerosene) is surprisingly competitive in densitie(s), it has density of 0.78-0.81 g/mL depending on the particular batch bought . I
(suspect) I might be able to isolate some fraction of it using my distilling apparatus that is less dense. eg: I have reflux tubes, and a computer
controlled mantle; so, in theory I could do a slow distill of the lower boiling point hydrocarbons and hope one of them is less dense?
I just don't want to waste a lot of time on it .... and be frustrated.
The main issue, I think -- is the typical shape of the hydrocarbon, whether branched propyl groups, methyl groups, or non-branched cyclic structure,
(I'm thinking of vanderwalls forces) Each shapes will have different physical interaction with the methyl groups in the methyl or isoporpyl borates;
eg: B[O-R]3 molecules.
In general, so isn't there's a higher chance of "Like" dissolving "Like" if they have the same shape?
The pentanes are ring structures, and so there isn't the methyl group sticking out anywhere. So, I'm hoping the "-anes" might not dissolve my
somewhat ionic liquid as much as hydrocarbons with methyl groups sticking out.
eg: there is a dipole moment in the ionic fluid, and no part of the methyl or isopropyl electrolytes is a ring structure. But, I really don't
know....
Wouldn't ring shapes be more likely to dissolve ring shapes, and branched methyl hydrocarbons dissolve other branched methyl hydrocarbons?
It's an experience issue.... there's too many exceptions to rules; and so many things I can try.
For example; There's only a limited number of things I can do to disturb molecule shapes that will still allow (or increase) the electrolytes ionic in
character; for example, I can add cyanide to displace some of the oxgen on the borons, or "nestle" in; Boron loves negative charges and will take on a
fourth negative charge very weakly held.
For example, Hydrogen peroxide (OH-)2's stick to boric .acid surprisingly well.
I would think the cyanide ion is similar in charge -- but doesn't have oxygen on it
I may be thinking of the problem wrong, but I don't have a lot of experience ... and there seems to be a LOT of exceptions to rules in chemistry..
 That's why I'm asking.
[Edited on 20-3-2020 by semiconductive]
[Edited on 20-3-2020 by semiconductive]
|
|
|
semiconductive
Hazard to Others
Posts: 287
Registered: 12-2-2017
Location: Scappoose Oregon, USA.
Member Is Offline
Mood: Explorative
|
|
| Quote: Originally posted by Twospoons | After skimming that huge wall of text, I get the feeling that what might work for you is an inert dry gas bubbler at the bottom of your electrolyte.
The flow will carry away your unwanted compounds faster than diffusion from the surface, and you wont get the O2 buildup above your electrolyte.
If you are unsure of the water content of your inert gas it should be simple enough to dry it using a suitable dessicant or a cold trap (or both).
|
Smirk.
Yes ... that would work. It would be about the same as a CO2 in a bottle with dessicant, right?. ( It's in the wall of text. )
Perhaps more inert, should I use helium or argon; They selling at around $85/a bottle in my local area.....
I've tried CO2 -- and my bottle ran out of gas before the experiment finished.
The problem is cost ... there's going to be a lot of failures when running this experiment; and I sometimes I have to go places and leave experiments
running under computer control with no monitoring for a week at a time.
Orange oil is $10 a bottle, and I get about ten tries out of it before it's too contaminated and has to be thrown out. It doesn't evaporate or go
away. Bubbles of O2 or H2 generally do not like to stay in warm liquids -- so most oil like substances should be sufficient. I run the experiments
anywhere from 25C to 40C.
I have wondered about making an oxgen scavenger, like a carbon monoxide generator ... because graphite and carbon are cheap, and would probably last a
long time. But I don't know how.
The only really bad idea I've had turns out to be fluronated oils ... I just proved something I ought to have known ... fluronated-oils are used for
artificial blood because the fluorine seems to "stick" to air and oxygen molecules better other liquids. They are the exception to the rule that
warming decreases solubility of gasses in liquids .... CPU coolant oils and FC's are a bad idea for electroplating aluminum.
|
|
|
semiconductive
Hazard to Others
Posts: 287
Registered: 12-2-2017
Location: Scappoose Oregon, USA.
Member Is Offline
Mood: Explorative
|
|
Many AKLANES have awesome properties and low toxicity and density ..
Some of them have lower repoted densities as liquids than their chain lengths would suggest;
I discovered a a process called "steam stripping" used to distil oils (alkanes or terpenes) at temperatures well below their boiling point when
researching everything I've been told;
Does anyone have experience with steam stripping, and could give me some anecdotes as to how difficult it might be to separate out straight chain
saturated Octane, Nonane, or cyclic CycloPentane, or CycloHexane from kerosine or perhaps coleman white-fuel?
I realize vacuum distillation is more efficient, but it also takes special pumps or aspirators; and hydro-distillation is something I can set up and
leave. I have a separtory funel, and can program it to drop a certain percentage of it's contents back into the still if re-cycling the water would
help the separations.
eg: I have vigereux columns, computer controlled mantle to 1degree C, water jackested distillation colums all 12 inch long or longer -- and am happy
to construct any standard o-chem distillation apparatus even with a few robitic additions .. but I don't really want to pour hundreds of gallons of
water down an aspirator for vacuum distilling.
Both cyclo-pentane (BP 38Celsius) and straight chain nonane (BP 150C) exist in kerosine. The problem is that anything above about 125C that I've
tried to distill without water, typically chars or burns (it is fuel, after all...) .... so if water can be used to lower the vapor pressure and
temperature needed to distill the oil; that's a skill I'd like to learn!
Also, it makes me curious if plant oils such as omega-3 and omega-6 might be separable by distillation, if carefully controlled temperatures were
maintained in the still. There are a lot of useful experiments that can be done if oils can be separated ....
|
|
|
sciece nerd
Harmless
Posts: 25
Registered: 27-8-2019
Member Is Offline
|
|
KOTf is potassium triflate.
|
|
|
clearly_not_atara
International Hazard
Posts: 2691
Registered: 3-11-2013
Member Is Offline
Mood: Big
|
|
| Quote: | | Cymenes are very similar to D-limonine, correct? |
Both cymene and limonene are monoterpenes. But cymene is aromatic, which lowers its reactivity. Limonene is an alkene and as such may react under the
conditions, which may be responsible for the loss of phase separation. It may be possible to convert limonene to cymene somehow e.g. by refluxing over
a transition metal catalyst or high-valent oxide like Fe2O3, CuO or Ag2O, but this is pretty speculative. Limonene's reactivity makes it a
non-innocent solvent for electrochemistry.
Cymene's side-chain has conformational entropy which lowers its density a little compared to benzene: 0.857 vs 0.876.
[Edited on 04-20-1969 by clearly_not_atara]
|
|
|
semiconductive
Hazard to Others
Posts: 287
Registered: 12-2-2017
Location: Scappoose Oregon, USA.
Member Is Offline
Mood: Explorative
|
|
| Quote: Originally posted by clearly_not_atara | | Quote: | | Cymenes are very similar to D-limonine, correct? |
Both cymene and limonene are monoterpenes. But cymene is aromatic, which lowers its reactivity. Limonene is an alkene and as such may react under the
conditions, which may be responsible for the loss of phase separation. It may be possible to convert limonene to cymene somehow e.g. by refluxing over
a transition metal catalyst or high-valent oxide like Fe2O3, CuO or Ag2O, but this is pretty speculative. Limonene's reactivity makes it a
non-innocent solvent for electrochemistry.
Cymene's side-chain has conformational entropy which lowers its density a little compared to benzene: 0.857 vs 0.876. |
Excellent. I assume that cymene is also an alkene, so that the least reactive is still going to be alkanes. I am interested to try to convert
limonene to cymene, just to see if it works ... most of the experiments I've been doing are speculative anyway.
I don't have red rust oxide; but I do have fools gold, FeS or FeS2, I've used it in the electroplating experiments along with pure iron .... I was
wondering about it compared to Fe2O3. Sulfur is supposed to be a lot like oxygen. But -- Fe2O3 puts Fe in the +3 state, and each of the oxides in
the -2 state.
However the iron pyrite equivalent of rust I think puts Fe in the +2 state? (I was a bit surprised it wasn't Fe2S3 ... so, when you say "high
valence", fools gold would probably not be a good choice of catalyst?)
Just to document what I succeeded in so other's know...:
I bought "ultra pure" lamp oil, (alkanes from Lamplight, inc. (R)), and had a brainstorm.... I put a drop of detergent into 200mL of methanol (eg:
heet brand water dryer is methanol.) The idea was to see if more soluble and smaller alkanes would dissolve (if possible) in methanol. Detergent
happily dissolves in methanol, and then I poured the kerosine / paraffin lamp oil into the same flask. I shook it up, and the two mixed tubidly and
then after a while settled with the methanol on bottom and it remained very foggy. Being as methanol is the smallest chain alcohol I could use, I
hoped it would be among the lowest density. It definitely absorbed something that was in the oil as there is more mass at the end of the experiment
in the methanol. Repeating the experiment with already washed kerosine doesn't make the next batch of methanol turbid.
Under washed kerosine, I'm able to run experiments for weeks without miscing happenng. So, it works well as an oxygen stopper.
Now for the fun part:
I've gotten aluminum to electroplate, very slightly, once; but it's got a lot of oxide mixed in and isn't solid. Not good enough. However, I *am*
able to electroplate both grey iron and golden iron pyrite. I found that Pyrite partially dissolves/complexes with citric acid in methanol; though
it won't plate from methanol it does plate in sulfide solutions.
The photo, here, is iron pyrite electroplated onto an aluminum anode at low current in a sulfide solvent (DMSO). The blacker portion was in the
electrolyte itself, and the small golden area was in the paraffin oil just above the electrolyte! Ions/chelates still penetrate into kerosine about
2mm. Probing it with a digital multimeter, the resistance increases either exponentially e^(-kx) or perhaps square law 1/x^2 the farther from the
bi-layer I make measurements.
So, i can make jewelry now!!! 
Iron pyrite is also a semiconductor.
[Edited on 29-5-2020 by semiconductive]
[Edited on 29-5-2020 by semiconductive]
|
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
