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updates: i've read what you guys have written, and i mostly (or maybe entirely) agree. i've made many/all of the changes you've suggested, and i also uploaded some additional images.
graham/grahams: does anyone have a definitive answer? who is this graham/grahams guy? and what is his actual name? if anyone finds a source, please update the article. — Preceding unsigned comment added by Fleximus ( talk • contribs) 12:48, 2 June 2011 (UTC)
I suspect that the "Graham condenser" is named after Scottish chemist Thomas Graham (1805–1869). He eventually rose to become Master of the Mint, but he was also consulted by the Board of Inland Revenue on matters concerning the taxation of alcohol (ethanol).
Graham's work on determining the alcohol content of beer involved distilling the wort in a retort in order to separate the alcohol (as stated on p. 255 of the report linked above). Later, distilling flasks that were connected to Graham condensers were used for that purpose, as is illustrated on page 320 of this 1975 article. I suspect that the switch from using retorts to using Graham condensers probably took place in the late 19th or early 20th century, when glassblowers were able to fabricate such complicated glassware at a reasonable price. (However, I still haven't found any proof of that.) I also suspect that although Graham probably never used such a condenser, it was probably named after his method of analysis as much as it was named after him.
VexorAbVikipædia ( talk) 01:20, 10 April 2017 (UTC)
I strongly believe the naming and descriptions on this page are either incorrect or confusing, specifically with regards to the coil, Grahams & Friedrich condensers. The article suggests, and illustrates, that a Grahams condenser can be run with the vapour traveling around the cooling spiral. If you investigate this with the big name glassware companies, this is a COIL condenser (or Dimroth if the water enters and leaves in a similar location). The version wherein the vapour travels through the spiral is the GRAHAMS condenser. I see people mixing the two up even on the better science forums, and then arguing over the technicalities due to the naming error. GRAHAMS condensers are also called INLAND REVENUE condensers.
A Friedrichs condenser is not simply a bigger COIL condenser. Inside, there is a cold finger with a spiral groove molded into it's edge. The finger is almost the same size as the outer glass shroud, forcing the vapours into intimate contact with the cold finger. This is an attempt to provide a large flow path but to also avoid solvent bypassing the the cold surfaces; e.g. in a COIL condenser, driving the solvent through aggressively can allow some of it to creep around the edges of the coil, which is why jacketing is sometimes used. The Friedrichs is another approach to that.
"A Graham condenser in the first configuration is used to prevent the toluene from boiling away while it is being refluxed."
That is a COIL condenser, NOT a Grahams. Note the water entering the sides and running through the coil.
Search the catalogs of Sigma, Quickfit and ChemGlass for these names, and you'll see they are being incorrectly transposed in the article. The only time there is a crossover is when Sigma call a COIL condenser a Coil (Grahams). However, this condenser is made by QuickFit in the UK, and checking their own page (SciLabWare), you'll see they have a distinct naming policy that differentiates the two.
I would rate this article as currently being critically flawed and in need of serious repair. [editor name not given]
Some pictures or drawings of the different glassware would improve the article immensely! Probably start by checking if there are any available on Commons. Larsenbagvendt ( talk) 10:50, 4 June 2010 (UTC)
There is no mention of a West condenser. Isn't this a Liebig with a narrower jacket? —Preceding unsigned comment added by 151.204.242.197 ( talk) 17:23, 12 February 2011 (UTC)
Even though the text tries to correct this mistake, a number of the diagrams have the coolant running in the wrong direction. The flow of the vapors and that of the coolant is supposed to be in opposite direction. (Coolant enters at top, exits at bottom.) Jcwf ( talk) 22:42, 31 March 2012 (UTC)
While some condensers will allow the water to flow in either direction some require the water to flow from top to bottom, or will be significantly more annoying to set up. 149.171.157.13 ( talk) 01:01, 27 April 2015 (UTC)
One reason that the foregoing issue exists, is that apart from Wiberg, this article is very poorly sourced. In this first pass, I will try to add, as "Further reading", further absolutely reliable sources, for futures editors to use. They will focus on German and UK practice. Cheers. 173.15.56.201 ( talk) 01:02, 12 February 2015 (UTC)
I have been engaging in a major academic sort of edit of the content of this article, as explained above, putting good source of information into the "Further reading" section, then slowly mining these sources for content related to the article. (The sources chosen are from a career of several decades in the field, spanning two continents and familiar with more.)
The editing has hit a snag as a result of well meaning efforts on the part of another editor to standardize the formatting of citations. To make the point, note the following. The useful, easily accessible content of the text in the "Further reading" section:
Is not the same as what one has at their fingertips from this edited text, made uniform by way of templates:
Please review the above, both as it appears here, and by clicking on edit, so you can see how different the two appear in markup (which is what we have to deal with while immersed in the editing).
I would make the simple points, (1) that in the second format, I have lost information that was in the first format, that I was using to create content, and (2) for regular subject matter experts that are editing, the first format is the more useful, and less cumbersome in markup.
As WP policies indicate that there is no single correct way to do science citations (and that one should seek consensus before making major changes to citation formats), I am asking that we hold on converting sources to templates until after the expert work on the content is finished. After that point, we can have a discussion about how best to convert to a uniform style (as an appropriate finishing touch, "end game" activity, rather than a requisite middle game one).
I have therefore asked the well meaning editor at his talk page—and am asking any others interested, by writing here—to allow me to continue my content work, without having to deal with major changed to the citations I add (edits which make my access to content for editing problematic).
Let's leave the format changes until later. Can we? After the major content editing is done,we can then discuss how to keep content, but make it all more uniform.
Le Prof 7272 71.239.87.100 ( talk) 03:37, 26 February 2015 (UTC)
There are numerous locations where the various structures of the condensers are referred to as a spiral. A spiral is typically 2D and the radius increases as you proceed around the spiral. I think a better word to use would be helix as that does describe it accurately. Is there any particular reason why they are called spirals and not helices? 149.171.157.13 ( talk) 01:03, 27 April 2015 (UTC)
Being a non-native speaker of the English language, I'm not sure what is going on here:
This article freely mixes four very distinct items, namely coolers, reflux condensors, distillation condensors and distillation columns under the same name.
I find this very odd, and rather disturbing from a safety point of view.
Is this common practice, or have i just stumbled over the worst wikipedia article that is older than a week and longer than ten lines?
Best regards, -- Maxus96 ( talk) 00:43, 30 November 2015 (UTC)
The simple Liebig condenser had a number of forerunners, as Jensen states in his article on the subject: Jensen, William B. (2006) "The origins of the Liebig condenser," Journal of Chemical Education, 83 : 23. (Available at: University of Cincinnati (Ohio) )
The identity of the inventor of the Liebig condenser is disputed: Two men could claim to have invented it in 1771, and another two could claim to have invented the condenser later and independently.
(1) In 1781, an anonymous pamphlet was published in French, presenting a retort with a condenser, which, the author proposed, could be used to distill brandy and salinate seawater aboard ships at sea. The pamphlet was: Nouvelle Construction d'Alambic pour faire toute sorte de distillation en grand, … (New construction of a retort in order to do every sort of distillation on a large scale, … ), 1781. On the title page of a copy that was in the collection of the state library of Cassel, Germany, was written "par Jean-Hyacinthe de Magellan" ([written] by Joao Hyacinth de Magellan). Magellan (1723–1790) was a Portuguese friar who settled in London and who wrote a book on heat (Essai sur la nouvelle théorie du feu élémentaire et de la chaleur des corps [Essay on the new theory of elemental fire and on the heat of bodies] (London, 1780)). (Speter, 1909b), p. 3 and (Schelenz, 1910), p. 1978 both mention this attribution to Magellan, although Schelenz suspected that the pamphlet had actually been written by Lavoisier. On p. 5 of the pamphlet, the Préface stated: "La première idée de la Machine distillatoire dont il sera question dans cet Ecrit, remote à l'année 1770. Il en fut d'abord exécuté différens modèles en petit, & notamment un dans le mois de Janvier 1773 ; enfin, peu de temps après, par les ordres de M. de Boynes, alors Ministre de la Marine, la Machine fut exécutée à Paris en grand, … " (The first idea of a distillation device that is the subject of this work, arose in the year 1770. Different models were executed at first on a small scale, and in particular one in the month of January 1773 ; at last, shortly afterwards, at the order of Mr. de Boynes, then Minister of the Navy, the device was executed in Paris on a large scale, … ) Illustrations in the pamphlet show a retort to which a tube was fitted. The tube carried the retort's vapors through a rectangular box, which acted as a condenser and in which cold water flowed from the condenser's lower end to its upper end — a counter-current condenser.
(2) The other claimant to being the earliest inventor of the Liebig condenser was the German scientist Christian Ehrenfried Weigel who published an article about his condenser in 1771: Weigel, Christian Ehrenfried, Observationes chemicae et mineralogicae (Goettingae [Göttingen], (Germany): 1771). (in Latin) As Fig. 2 on the last page of his book, he shows his condenser. The parts are identified in a footnote on p. 11, and the condenser's construction is explained on pp. 8–9. The condenser consisted of two coaxial tubes made of pure tin. The condenser was tilted; at the condenser's lower end, the gap between the tin tubes was sealed with sheet metal; the condenser's upper end was open, allowing water to be discharged into a funnel, which emptied into a drain. A collar around the open upper end prevented the discharged water from streaming down the condenser. An inlet tube in the condenser's lower end allowed water to enter the condenser from an elevated reservoir, which discharged into a funnel that was joined to the condenser's inlet. A glass tube that extended from a retort at the condenser's upper end passed down the middle of the condenser's inner tin tube; at the condenser's upper end, the glass tube was supported by strips of sheet metal that were soldered onto the tin tube's inner surface and that held the glass tube in the center of the condenser. (See Fig. 4.) This arrangement avoided the danger of the glass tube's shattering, as might happen if the glass were in direct contact with the cold water of the condenser while a substance with a high boiling point were being distilled. In a second volume of his book on chemistry and mineralogy — Weigel, Christian Ehrenfried, Observationes chemicae et mineralogicae, part 2 (Gryphiae [Greifswald], (Germany): 1773). (in Latin) — Weigel mentioned a modification of his original condenser in which the inner tin tube had been replaced with a glass tube, which was secured to the outer tin jacket by plaster. Weigel also devised a clamp to hold his condenser; the clamp consisted of a pair of fork-shaped jaws which were closed by a screw.
(3) According to Jensen, in 1779 "P.J. Poisonnier" described a condenser of his own design. However, "P.J. Poisonnier" was actually P.I. Poisonnier — Pierre-Isaac Poissonnier — physician to Louis XV. In 1763, the French navy built and tested a still that he had designed in order to allow ships at sea to produce fresh water from seawater.
(4) The Swedish-Finnish scientists Jakob Gadolin and his son Johan Gadolin also designed condensers similar to Weigel's.
(5) Jensen also cited a discussion of Weigel's condenser by the German chemist Johann Friedrich August Göttling, who urged pharmacists to use Weigel's condenser (instead of the traditional still) because it was compact. (Göttling was a former student of Weigel.) See: J. F. Göttling, Taschenbuch für Scheidekünstler und Apotheker (Pocket book for [chemical] analysts and apothecaries), 15th ed. (Weimar, (Germany): Hoffmannische Buchhandlung [Hoffmann's bookstore], 1794), pp. 129–135.
(6) Liebig's contributions to the development of the laboratory condenser seem to have been: (1) eliminating Weigel's inner metal tube and allowing direct contact between the cold water in the condenser's jacket and the glass tube containing vapor from the distilling flask ; and (2) when distilling small quantities, using a glass tube, instead of a metal one, as a jacket for the condenser. However, so far I haven't found any evidence that he ever fused a glass jacket to the inner tube carrying the hot vapor.
(7) Reviews of the history of distillation:
I'm still reviewing these sources (some of them contradict others). However, I intend eventually to modify the subsection on the Liebig condenser to include material from these sources.
VexorAbVikipædia ( talk) 23:23, 5 April 2017 (UTC)
I cannot make sense of Widmer's condenser. There seem to be no way to remove the heat of condensation. Either the description is wrong, or the device's purpose was not to condense vapors.
Was the device merely intended to ensure better mixing or a more uniform and constant temperature in the outgoing vapor stream?
Could it be that the device was only Widmer's idea of a "better condenser", but he did not understand the physics of heat transfer and did not see the need for a coolant flow? Was his design ever used in practice, by Widmer or anyone else?
Or is the diagram wrong, and the middle "rod" was actually a cold finger with internal water flow (as in Friedrichs' design)?
Also, I cannot see the point if having the vapor flow in countercurrent next to itself, twice. That arrangement would make for a pecular heat flow between the first, middle, and last third of the vapor stream. To what purpose?
--
Jorge Stolfi (
talk)
18:49, 18 February 2020 (UTC)
Is there a better picture to illustrate the lead than File:Distillation 2-3.jpg? I can identify at least three serious safety hazards in it. (1) Distilling from an isomantle; a no-no except for purifying large volumes of solvent. (2) No means of removing the heat source in a hurry, such as a scissor jack. (3) No support for the flask other than the mantle. If the clamp twists, the GG joints either side of the anti-splash bulb will spring. If the liquid is flammable...
I don't much like the way that the water supply is out of reach or the kinks in the hose either. Narky Blert ( talk) 10:28, 23 February 2020 (UTC)