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Author: Subject: Carbon Disulfide Preparation
BromicAcid
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 Quote: It should also be possible to replace the carbon by PE (polyethylene). PE can be used instead of carbon in many reactions I cannot see why it shouldnt work here.

Well, Organikum I've kind of come back to this advice of yours. I was thinking about the lab preparation of H2S by mixing sulfur and paraffin in a test tube with glass wool. By heating the test tube H2S is evolved. This reaction is anologus to the reaction between propane and sulfur to form hydrogen sulfide and carbon disulfide, I actually have to wonder how much CS2 would be evolved from that lab scale prep of H2S. So, I figured that maybe the reaction between paraffin and sulfur would have a higher yield of CS2 if one could get the temperature higher, which would mean making the paraffin go to a higher temperature.

Going beyond paraffin’s which are classified as one web page said as having boiling points between 250 and 350 C and chains of carbons between 24 and 36 carbons in length, you come to asphalt, boiling point in excess of 550C, carbon chains greater then 40 molecules in length. These will allow for higher temperatures and hopefully when mixed with sulfur, a decent yield of CS2, while cutting down a little on H2S production compared to propane. Asphaltum is available readily and cheaply OTC for artistic projects, 400g for $1.25 as one web site sells it. I think the asphaltum will afford a lower reaction temperature then carbon alone and as such make the reaction more feasible. I’ll probably just use the H2S evolved to make some hydrobromic acid or something simultaneously then burn the exit gasses. Still though, this is a long ways off, it’s winter here, and it’s cold. Shamelessly plugging my attempts at writing fiction: http://www.robvincent.org Thomas Winwood Harmless Posts: 43 Registered: 16-12-2004 Location: United Kingdom of Great Boredom Member Is Offline Mood: Anhydrous Re: propane and sulphur Here's the result of a little brainstorming: The propane/sulphur reaction isn't difficult: 5S<sub>8</sub> + 4C<sub>3</sub>H<sub>8</sub> ---> 12CS<sub>2</sub> + 16H<sub>2</sub>S So what do you do with the hydrogen sulphide? I thought maybe you could oxidise it with something like a permanganate: 8MnO<sub>4</sub><sup>-</sup> + 8H<sub>2</sub>S -> 8MnO<sub>2</sub> + 8H<sub>2</sub>O + 4O<sub>2</sub> + S<sub>8</sub> (Stoichiometric quantities of everything would be useful here to make sure you have enough permanganate to oxidise all the H<sub>2</sub>S and so on.) The sulphur could, if you set it up right, be passed back through to be reused. (The intricacies of how you pass back the sulphur I haven't considered. It was a thought that only just came to me while writing this post. My initial mental apparatus called for a solution of KMnO<sub>4</sub> through which the H<sub>2</sub>S was bubbled. If you want to collect the sulphur you'll need something more fancy.) [Edited on 22-12-2004 by Thomas Winwood] chloric1 International Hazard Posts: 1039 Registered: 8-10-2003 Location: closer to the anode Member Is Offline Mood: Strongly alkaline  Quote: Originally posted by Polverone I have read somewhere or other that sugar charcoal does not work as well as coke for this reaction, simply because sugar charcoal is too pure. The addition of a small amount of alkali carbonate is supposed to have a catalytic effect. Polverone, I am interested in your carbonate catalyst statement. I contemplate the mechanism is based on momentary formation of alkaline polysulfides which would contain"active" sulfur atoms stripped of some of their valence electrons. Anybody agree with my thinking? Can anyone dispute it? I am curious for sure. Some other thoughts concerning preparation: Activated charcoal for fish tanks could be charged with a potassium carbonate solution and then baked at 200 or 300 fahreinheit to drive off water. Then maybe tis charcoal could be loaded in a cast iron pipe in a charcoal fire to red heat and sulfur could be melted and boiled to release vapors through the pipe to a cooling coil and into scrubers. [Edited on 12/23/2004 by chloric1] [Edited on 12/23/2004 by chloric1] In the theater of life its nice to know where the exit doors are located. BromicAcid International Hazard Posts: 3017 Registered: 13-7-2003 Location: Wisconsin Member Is Offline Mood: Legitimate CS<sub>2</sub> again.... and nothing good to report. I made a metal retort from iron pipes and attached a 24/40 ground glass adaptor into the mess so I could hook it to my distillation setup. I put 5 hollow aluminum rods into the metal pipe to help with heat conduction, they didn't fill it by a long shot but they made a little pentagon in it. 9 grams of airfloat carbon and 48 grams of sulfur along with a pinch of sodium carbonate were well mixed and put into the pipe, not filling it much. This was hooked to a standard distillation setup and the exit gasses were run into water basified heavily with KOH. The reaction mixture was then heated with the aid of a propane torch. Within five minutes there were whisps of gas appearing in the still head. They entered into the condenser without condensing and the temperature in the still head rose slightly (5 C or so). The gas condensed slightly on the glassware, it may have been sulfur. Some of it made it all the way though the apparatus and passed through the was without being absorbed noticeably, I didn't notice a smell to them either. Eventually thick yellow/white gas made its way out of the metal retort and into the still head condensing as a solid sulfur. More would come up and travel further down the condenser, and more and more, the condenser had sulfur in it about halfway down and still the still-head was at only about 40C. About thirty minutes into things, things started to get interesting. Inside the still head I noticed that the sulfur was dripping back down into the flask. I felt the glass and although it was hot it was not near the necessary temperature to melt sulfur. Looking closer I could easily differentiate white drops and yellow drops. The identity of the white drops was confirmed a few minutes later when some began to merge within the condenser, and flow, leaving behind sulfur. CS<sub>2</sub> huzzah (see attached picture)! White from dissolved sulfur they cleared up once they started to move and travel down the condenser, appearing faintly yellow. This went on for some time, with barely any liquid coming over, a drop every 5 minutes or so. Meanwhile I was getting some odd smells, maybe some H<sub>2</sub>S mixed with some SO<sub>2</sub> so I got curious about the washing. I went to my shed and grabbed some powdered copper sulfate. Figuring if I added it to the mixture I would either get black copper sulfate or copper metal or something. I poured the powder in and the soluiton immediately went black. Dark black. Hum.... I added some KOH pellets to the water to keep things basic and pondered that while I watched the insulation burn off my apparatus. When I got back to the wash bottle I found that it had settled and there were bands of black on top and copper metal shiny on the bottom, neat! The reaction had been going about an hour and the gas evolution had stopped completely despite the torch being on high. So I gave up. I turned off the heat and allowed to cool for an hour. Opening up the inside of the pipe I found absolutely no sulfur condensed on the inside walls and a small amount on the inside of the 24/40 adaptor, must have been too hot for it. The mixture in the bottom had solidifed and I couldn't remove it. Overall I got maybe 2 - 4 ml of CS<sub>2</sub> a really patetic yield. Maybe next time I will use activated charcoal and hope for better results. Shamelessly plugging my attempts at writing fiction: http://www.robvincent.org Eclectic International Hazard Posts: 899 Registered: 14-11-2004 Member Is Offline Mood: Obsessive Has anyone tried running sulfur vapor into a combustion tube full of yellow-hot charcoal and condensing the result? Or putting the sulfur-charcoal mix in the bottom with a layer of pure charcoal on top and heating from top down? It seems like just heating a mix of charcoal and sulfur will drive the sufur off before you get any significant reaction with the charcoal. Oh! Nevermind. This was mentioned a while back... [Edited on 9-10-2005 by Eclectic] al Harmless Posts: 10 Registered: 8-10-2005 Location: France Member Is Offline Mood: No Mood Carbon sulfide - CS2 Here is a very good method to get CS2. Berzelius wrote about it . Distillate wax or paraffine + sulfur in a flask. CnH(2n+2) + (3n+1) S -----> n CS2+ (n+1) H2S You get an escape of H2S and CS2 vapors you may condense in water. CS2 heavier than water has a yellow color, you need to distillate it carefully in order to get the colorless CS2. Other way to get H2S I heated 1/2 hour to 700° C a mixture of plaster of Paris an carbon : 200 g plaster for 50 g of wood carbon (powder) I got a grey compound : CaS. It reacted a little with water giving H2S, but with hydrochlorhydric acid it gave a very strong escape of H2S. To determine the yield , you may use the calcimeter flask : the weight difference gives H2S , ... so the yield. BromicAcid International Hazard Posts: 3017 Registered: 13-7-2003 Location: Wisconsin Member Is Offline Mood: Legitimate Al, see my first post on this page. Heating parafin with sulfur and glass wool is a time tested way to make hydrogen sulfide, but I've never actually heard of CS<sub>2</sub> being produced, I figured I was just speculating, like I say in that post though, I don't think the reaction would go to completion as the parafin would volitize away leaving the sulfur eventually, although the glass wool would help. That is why I was thinking about using asphaltum. I found a nice little review on carbon disulfide manufacture in pdf format, I could have swore it said that there was no catalytic activity of alkali carbonate even though erlier sources said there might be, although that may have been in a different document. PDF on Carbon Disulfide Production Methods Shamelessly plugging my attempts at writing fiction: http://www.robvincent.org garage chemist chemical wizard Posts: 1803 Registered: 16-8-2004 Location: Germany Member Is Offline Mood: No Mood @ al: Can you give us the original report from Berzelius, which contains correct procedure or at least ratio of reactants (if different than stochiometric ratio according to the equation, which suggests 1 mol paraffin and 3 mol sulfur)? That would be nice. I'll try out this procedure with paraffin and sulfur. Sure enough, it is normally a procedure to make H2S, but the ratio of sulfur and paraffin seems to be very imporant here. I think that first the hydrogen of the paraffin completely reacts with the sulfur, leaving finely divided carbon (this is confirmed by the production of a coke deposit from this reaction) to form H2S. Then excess sulfur (the extra 2 moles) reacts with this special form of carbon to form CS2. H2S and CS2 could be produced one after the other by first heating gently producing H2S and then stronger to produce CS2. H2S is absorbed best by bubbling through NaOH solution, forming Na2S which is highly useful. I tested this with pure H2S (from ZnS and HCl) and the H2S is absorbed completely and very vigorously (be careful of suckback! Use a safety bottle or use a washing bottle with a pipette-tip, this is efficient in preventing suckback as I've found out). If an excess of H2S is used, NaHS will form, but this can be turned into Na2S by adding an equimolar amount of NaOH. A very promising alternative to paraffin would be polyethylene. It doesn't boil but melt and react completely with the sulfur. I have some old PE canisters that I'll cut up and heat with sulfur in the molar ratio 1:3 (PE:sulfur). ordenblitz National Hazard Posts: 254 Registered: 18-7-2004 Location: Northwest Member Is Offline Mood: Bohr'd Skylighter sells polyethylene powder for$5.35 a pound, in case you didn't want to mess with snipping up containers.

http://www.skylighter.com/
garage chemist
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Today I tried to make CS2 from polyethylene and sulfur.

I cut up 1,4g (0,1 mol) of HDPE (from an old canister) into very small pieces and added 10g (0,33 mol) of sulfur.
This was put inside a 100ml round- bottom flask.
Upon heating, lots of H2S was first produced, as expected (I worked in my fume hood), and the mixture became black.
Yellow smoke billowed out of the reaction vessel and coated the inside of the apparatus with fine elemental S.
I ran icecold water through the liebig condenser the whole time.
As the H2S production slackened, it was obvious that the rxn vessel now contained some kind of coke and the unreacted sulfur.
No CS2 distilled over, not a single drop, despite heating the vessel until the sulfur boiled.
10 extra grams of sufur were added and heated again, still nothing.

After this experiment I cleaned the flask by boiling some NaOH solution in it, this was very effective (If such a good cleaning method wouldn't exist I wouldn't have even thought about using my precious ground- glass equipment for this!).
A residue of coke was left when all the sulfur had dissolved, it was porous and brittle.

I then tried out paraffin + sulfur (1,4g + 15g), in hope that Berzelius actually improved the process of CS2 production over the charcoal/sulfur process with that.

Again the same, lots of H2S and no CS2, but this time even nastier mess inside the flask due to the paraffin partially evaporating and coating the inside with tar.

Carbon disulfide has so far resisted every attempt at its preparation (I tried charcoal + sulfur before, with and without catalyst, and also heating a test tube with sulfur in the lower part and charcoal in the upper part from the top down- still nothing).

This drives me crazy... it just can't be possible that charcoal + sulfur at over 800°C or methane + sulfur at 900°C are the only methods of preparation!

Maybe the carbon needs to be in a special active form to react to an appreciable degree at 400°C...

My new idea is to heat calcium carbide with sulfur, this should theoretically yield calcium (poly)sulfide and CS2. But since CaC2 doesn't react with oxygen even at 1000°C (only the nitrogen in the air reacts, forming calcium cyanamide), my hopes are low for this. I'll try it anyway.

Acetylene and molten sulfur react to form thiophene, sadly.

Any other unconventional ideas?

Maybe something with hydrogen persulphide... this is a strong oxidizer like H2O2 (it also bleaches hair and tissue like H2O2), but with sulfur instead of oxygen.
Its preparation is easy, boil Na2S solution with sulfur to form polysulfide, then drip this solution into HCl, the hydrogen persulphide separates as an oil, care must be taken as it can spontaneously and violently decompose in the presence of bases or other catalysts.
Maybe this is able to oxidise charcoal or some organic compound to CS2...

In Hollemann- Wiberg, hidden in some other article, I found the reference that an early experimenter accidentally prepared "sulfur alcohol", as he called it (it was actually CS2) by heating pyrite (FeS2) with charcoal.

Now, where can I get pyrite? Can I prepare it by reacting sulfur with FeS or directly two moles of S with one mole of Fe?
Does anyone know if it is possible to prepare artificial pyrite or where to get the mineral?

[Edited on 2-11-2005 by garage chemist]
12AX7
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Doesn't particularly suprise me... what temp does carbon burn with oxygen?

Just use a heated, sulfur-resistant tube loaded with charcoal. Pass S vapor through it and condense yon CS2.

Pyrite? That would be interesting. Is carbon electronegative enough with respect to iron to remove sulfur, or is only the extra S reduced? (2FeS2 + C = CS2 + 2FeS, which is stoichiometric.) You can make it by direct synthesis, yes. I don't know of any source of the mineral, but eBay might be worth a try (unlikely since the only specimens would be top quality masses of crystals, but who knows, maybe someone has it in bulk).

Tim

[Edited on 11-2-2005 by 12AX7]

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garage chemist
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Today I went to the university chemistry library and looked up, among other things, the production of CS2.

My reference was the Gmelin Handbook of Inorganic Chemistry. With about 5000 Volumes it contains nearly the entire chemical knowledge of humanity on inorganic chemistry.
There was a 250- page volume dedicated exclusively to compounds of carbon with sulfur!

Covered were the different industrial processes to effect the reaction of carbon with gaseous sulfur, methods employing electrical heating by current flowing through the charcoal bed were also described. Same for the various processes employing hydrocarbons and sulfur vapor (all requiring superheated sulfur vapor above 600°C, sadly).

The reaction of charcoal with pyrite was also described, and nearly quantitative yield of CS2 was stated!
The reaction goes to completion, producing elemental iron, which means that FeS made by the well- known reaction between iron filings can also be used.

FeS2 + C ----> Fe + CS2

No temperatures were stated though. This could be the biggest problem, since the high temperature required is also the main problem in phosphorus production.

For the issue of producing high temperatures, I have found that a propane- oxygen torch is capable of softening quartz, more than just a tiny bit.

If a chemical mixture (like for example bone ash + charcoal + SiO2 !) has to be heated to over 1000°C, I would put it in a quartz test tube (available from Ebay for less than 10\$)
and heat it with a propane- oxygen torch.
Bright yellow heat is very easy to achieve.

[Edited on 5-11-2005 by garage chemist]
chloric1
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Mind the ignition point. CS2 ignites at about 100C. If there is a leak in your aparatus you could have a flash explosion.

In the theater of life its nice to know where the exit doors are located.
garage chemist
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5,6g Fe filings and 3,2g sulfur were mixed and ignited to give FeS. The identity of the product was checked by adding some of it to HCl, H2S stink was produced at once.

The FeS was powdered, mixed with 1,2g charcoal powder and put in a Duran test tube.
It was heated with a bunsen burner.
Soon the evolution of gas was apparent and the powder even was thrown around a bit.
Colorless drops of liquid condensed in the upper part of the test tube.
The liquid was soaked up with a strip of blotting paper and tested for flammability.

It didn't burn.

It was just moisture from the charcoal.

I heated the test tube with a propane- oxygen torch until it was glowing yellow and the glass got a blister because it started to melt.
NOTHING.
garage chemist
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OK, I did some patent research and can now see the superiority of the sulfur+propane process when done right.
The temperature of boiling sulfur is high enough to effect the reaction with propane.
Bubble propane through boiling sulfur.

The problem is that the CS2 can not be condensed completely from the exit gas. Too much H2S is present, the partial pressure of CS2 is too low to allow its complete condensation.

The unreacted sulfur first needs to be removed from the gas stream.
Due to the tendency of sulfur to not condense on the walls of a condenser, but rather as a fine yellow smoke of solid sulfur, I would use a gas washing bottle stuffed with glass wool for the removal of unreacted S.

Then a condenser in which most of the CS2 condenses.

The next stage, the CS2 absorption unit, would consist of a gas washing bottle filled with heptane or just simple petroleum.
CS2 dissolves into it and can later be recovered by distillation.
Choose a petroleum type of high enough boiling point in order to facilitate the separation. If necessary distill your petroleum before use and discard everything coming over below 100°C.
And don't use too little petroleum, fill your washing bottle up to its designed capacity, the absorption capacity of petroleum for CS2 is limited.

Then the most important step, absorption of H2S.
Alkali is the way to go. A washing bottle with NaOH solution would do the job nicely, I speak from experience.
However, the problem is suckback. H2S is absorbed rather violently.
Maybe a column with soild NaOH (or Ca(OH)2 if it works) is better here since it eliminates this risk.

The whole apparatus will need to be located under a good fume hood and operated after midnight, when nobody is outside, due to the inevitable smell evolution. Getting a H2S apparatus smelltight is next to impossible, I know that by experience. Silicon and PVC hoses hold up great, but diffusion of H2S through the walls is very noticeable.

[Edited on 6-11-2005 by garage chemist]
neutrino
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Is CS<sub>2</sub> stable in basic conditions? If it is, wouldn’t it be easier to remove the hydrogen sulfide in the gas stream and then condensing the CS<sub>2</sub>?

If you want a high bp petroleum, try mineral oil. It is available pure at any pharmacy and has a bp well over 250*C
garage chemist
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CS2 reacts instantly with alkali sulfide solutions (such as that produced by reaction of the H2S and NaOH), producing a solution of trithiocarbonate. So better first condense and wash out the CS2 and then dispose of the H2S.
Another solution to the H2S issue would be burning of the H2S, e.g. feeding into the air input of the bunsen burner. The SO2 creates far less stink than the H2S, which even I with my tolerant neighbors cannot blow out of my fume hood in such amounts.

I have some doubts if propane and sulfur will actually react rapidly enough and in the desired manner. Propane is said to give problems due to coke formation.

Anyway, today I went to the pharmacy and asked if they could order 250ml of carbon disulfide for me. The short conversation was interesting. Full report here when they have called and informed me if they will sell it to me.
garage chemist
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From "Mercks Warenlexikon", it describes the construction of a small- scale carbon disulfide furnace fired with charcoal:

Schwefelkohlenstoff (Schwefelalkohol, Kohlenstoffbisulfid, Sulfokohlensäure, lat. alkohol sulfuris, carboneum sulphuratum; frz. sulfure de carbone; engl. sulfuret of carbon). Aus zwei festen Körpern, Schwefel und Kohle, entsteht, wenn sie durch Glühhitze zur Verbindung gezwungen werden, der S., oder wie er von seinem ehemaligen Entdecker, Lampadius in Freiberg, genannt wurde, Schwefelalkohol. Bei Bereitung desselben kommt es darauf an, Schwefel in Dampfform durch glühende Kohlen streichen zu lassen. Die Apparate hierfür haben eine, in einem Ofen stehende, von unten zu beheizende Retorte von Thon oder Eisen, im letzteren Falle innen mit Thon ausgekleidet. Sie wird mit Holzkohle in haselnußgroßen Stückchen gefüllt und angefeuert, bis die Kohlen hell glühen. Es wird nun nach Bedarf ganzer Schwefel eingeworfen durch ein Rohr, das von außen in die Retorte und bis nahe an deren Boden führt und immer rasch wieder geschlossen wird. Der unter den Kohlen schmelzende und verdampfende Schwefel durchzieht dieselben, sättigt sich mit Kohlenstoff und die neue Verbindung zieht oben dampfförmig durch ein Knierohr ab, das durch eine Kühlvorrichtung geht. In einem zwischengelegten Gefäße schlägt sich erst der unverbunden mit fortgegangene Schwefel nieder; das übrige geht weiter, verdichtet sich tropfbar und sammelt sich in einer Vorlage unter Wasser, denn der S. ist schwerer als dieses und mischt sich nicht mit Wasser. (...)

I'll translate it when I have time.

I can also get a drawing of the apparatus, it's in my school and I have to copy it.

[Edited on 8-11-2005 by garage chemist]
chloric1
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 Quote: Originally posted by garage chemist Anyway, today I went to the pharmacy and asked if they could order 250ml of carbon disulfide for me. The short conversation was interesting. Full report here when they have called and informed me if they will sell it to me.

I would not be surprised if they sent the feds to your place. But maybe Germany is more friendly to intellectuals than the USA? Curious to see if you get any static at all.

In the theater of life its nice to know where the exit doors are located.
chemoleo
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 Quote: CS2 reacts instantly with alkali sulfide solutions (such as that produced by reaction of the H2S and NaOH), producing a solution of trithiocarbonate.

Well, shouldn't it then be possible to revert this reaction, by i.e. adding a strong acid to get back CS2? Similar to getting CO2 from Na2CO3 and acid?

Maybe you ought to order trithiocarbonate from the pharmacy instead.

What exactly did you tell them to convince them to sell CS2?

I remember once purchasing 1 l of 80% phenol from the pharmacy. It took a bit of convincing, but I said I wanted to make bakelite. The pharmacist loved me for my enthusiasm!

[Edited on 9-11-2005 by chemoleo]

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chloric1
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Yes, I can see already things are different. Most "pharmacists" I have meet in the US of A actually hate chemistry or are indifferent to it. It seems they are in it only for the money. Some of the prissy girls would instantly be suspicious if I asked for anything like that.

Don't get me wrong a few have a passion for the central science. But most just want the green.

In the theater of life its nice to know where the exit doors are located.
garage chemist
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Hmm, no luck here, despite the pharmacist being willing to order some CS2 for me.

When I first asked for CS2, the immediate first answer was: "We don't sell chemicals because we don't know what you are going to do with them! For what do you need carbon disulfide?"
"As a solvent for sulfur and phosphorus", I answered.
"And then?"
"I am a hobby chemist!", I said.
She said that she will phone her supplier and ask what this (250ml) will cost.

The next day I was told on the phone that the minimum amount I could buy was 1 Liter, and that it would cost 99€.
Of course I was not willing to pay this astronomic price, I opened Mercks CD catalogue and printed out the product site for 1 Liter Carbon disulfide, the price being 35,75€.
With this I went into the pharmacy again, she said "That's very interesting!", because the supplier who got his chemicals from Merck was the one who charged that ridiculous price.
Today there was no phone call, I called the pharmacy myself and was told that another supplier only sells at least 3 Liter of CS2, the price for it being 90€ (plus tax, plus shipping and plus the money the pharmacy wants to make, mind you!).
The pharmacist faxed Merck directly and asked if CS2 is available in amounts of less than one liter, and in lower purity grade than "Extra Pure" (technical grade would suffice for me). The answer to this fax has not arrived yet.
I was also given the adress of a local chemicals redistributor, but they were closed already because it was too late today.
Tomorrow I won't have time, sadly...

So I'll have to wait. But atleast I know that I would have got my CS2 if there had been a supplier who sold small amounts.

That is the actual problem today: the big companies refuse to sell in small amounts.
"Too much hassle for too little profit", they think.

My only hope now is this chemical redistributor.

A few tips when buying chemicals from pharmacies:

The most important thing is to tell them that you are a hobby chemist.
Most of the chemicals we want have absolutely no use for the average citizen, and the pharmacists know that.
They also can NOT, I stress this, send the police to your house. The worst they can do is refuse your order. And there are a lot of pharmacies in cities. New pharmacy, new luck.
It is of course very unwise to order listed drug precursors, this could actually get you into trouble.
But CS2, for example, is no drug precursor, and also no explosives precursor. The only problem is its toxicity and flammability.

Also, know the price that big chemical companies charge for your wanted substances (search in their online catalogue), because the pharmacists don't search for the cheapest seller. This is important to avoid paying ridiculous prices.

If you don't try to get your substances in the pharmacy, you can't complain about chemicals being hard to get.
It is one thing to save some money or avoid some hassle by using OTC chemicals or synthesizing chemicals yourself, but another thing to spend months trying to make a stupid SOLVENT. It will eventually be much more expensive than ordering it, even if the price may seem high, and much more work.
The example above of the pharmacy not being able to order the desired small amount is actually an exception, I got quite a bit of chemicals in the pharmacy before (it was another pharmacy, the one in which I asked for CS2 had never seen me before).
garage chemist
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Today, on december 24th, seven weeks after my first inquiry about the carbon disulfide and after numerous other calls to chemical suppliers and visits to the pharmacy, the pharmacy phoned to tell me that my carbon disulfide had arrived.

I went there immediately, paid the price and thanked them for their cooperation.
The long delay was the fault of the supplier who didn't have the CS2 in stock and had to order it first.

The 1 L bottle of "Carbon disulfide, extra pure" from Schuchardt (re-sold by Köhler) has now found a place on my chemical storage shelf.

What a wonderful christmas present!
neutrino
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Very nice. What was the price of this bottle?
garage chemist
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The list price was ca. 36€, but after adding taxes, enormous shipping fees and the amount the pharmacy wanted to make the price was at 56€.
It was still OK since I am going to give some of this to other hobby chemists in exchange for other chemicals. The entire liter would be too much for me.
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