Questions tagged [distillation]

For questions about the process of distillation. For the distillation process used in metal refining, also use the [metallurgy] tag.

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Does each liquid in a binary mixture boil at its boiling point? [closed]

I have been looking for an explanation and can't seem to find one, so I am asking my question on this forum. I appreciate your responses. Consider a binary mixture of cyclohexane and toluene (50% mol:...
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Breaking an azeotrope by using different atmospheres?

I read the threads about azeotropic mixtures and distillation, and a question arose: Is it possible to distill an azeotropic mixtures properly (i. e., separate it into its single components) by ...
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Could fluorinated gases be removed from the atmosphere? [closed]

Background Among all the discussion of 'greenhouse gas removal' (GGR) to aid climate change mitigation, almost all is concerned with removal of carbon dioxide. There are one or two mentions of ...
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Why is NMP developing a yellow color after distillation?

I got an aqueous mother liquor of N-methyl-2-pyrrolidone (NMP) from some reaction I was running and when I redistilled it under vacuum, it came out colorless but turned yellow the next day. I am ...
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Does yeast, sugar and water really produce any noticable/significant amounts of methanol?

I just read this question on Quora about distilling during pre-industrial age, which reminded me about multiple discussions I have heard or read during the years about whether the fermentation process ...
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Stratification of gasses by mass [closed]

Suppose a homogenous mixture of mutually non-reactive gases is isolated in a container so that there are no external kinetic forces (vibration or rotation) that create turbulence or other mixing ...
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Distillation of water and propanone

I distilled a solution consisting of propanone and water and recorded the boiling point of propanone depending on different concentrations. I thought that the boiling point elevation would be the ...
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What factors have the greatest effects on the yield from steam distillation of ginger?

I have a modest home lab setup that I use primarily for steam distillation of plant matter to extract essential oils. My yields are typically at or below the low end of estimates given by different ...
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Does distilled water still have ions in it? Does deionized water lack ions, but still have other "stuff" in it?

This isn't a question about the difference between Deionized and Distilled water, my hope is that for once it's actually a chemistry question related to this topic. Distilled water is created by ...
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Why does the ethanol-water mixture not burn during fractional distillation?

Ethanol-water solution has a flash point lower than ethanol's boiling point in almost all cases. So how is the fractional distillation of the solution possible? Why doesn't the solution ignite? Is it ...
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Can ethanol and heat during distillation cause degradation/dissolution of vinyl tubing leading hot vapors of the distillate to the condenser?

I'm a chemist and a qa lab, and we occasionally test herbal remedy products from one of our customers for alcohol content using a distillation, then using the specific gravity of the distillate to ...
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Alcohol (ethanol) distillation: mystery congener

I regularly home-distil small amounts of potable alcohol (ethanol), mainly from fermented sugar(s) solutions (the 'wash'). My still is a box standard, $4.5\mathrm{L}$ electrically heated (safety!), ...
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Can the enrichment of Uranium be done via manipulating the boiling/melting point difference between differing isotopes of the same element?

I have a Physics question for which I could not find the answer on the Internet, so I would like to see if y'all know the answer to it. I have found that heavy water will have a different boiling ...
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Doubt regarding steam distillation

According to my textbook, in steam distillation the liquid boils when the sum of vapor pressure due to the organic liquid and that due to water becomes equal to the atmospheric pressure. Why? I did ...
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Why should the conical flask (apparatus on the right) used in Fractional Distillation be left open (without a bung)? [closed]

With context to the image shown, is there a reason as to why the conical flask shouldn't be closed with a bung and is there a way to describe this error?
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steam distillation vs fractional distillation

I am a high school student and I am a little confused in the techniques used to purify organic compounds, for e.g we study in steam distillation we reduce the external pressure on the compound to be ...
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Is there such a thing as a temperature-controlled reflux column?

You know the deal - you're doing a distillation in the lab, but want a fraction that comes over at a very specific temperature. I find it very hard to control the temperature in my air-cooled reflux ...
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Is it possible to vacuum distill citric acid?

I'm wondering if it is at all possible to vacuum distill citric acid without the slightest decomposition; it is something that can easily be done in a small lab with widely available equipment. I've ...
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How concentrated does sulfuric acid need to be for nitric acid synthesis (H2SO4 + nitrate salt distillation)?

So I have a home lab setup and recently found myself in need of some nitric acid. I could just buy some, but I thought it would be a useful exercise to make my own. I have plenty of nitrate salts ...
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Are all gases equal in their ability to carry with them lower volatility matter at a given temperature? [closed]

As we all know water is a great solvent in it's liquid form relative to other substances. I wonder however how it performs as a gas relative to other stuff. Does anyone know how well steam carries ...
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Why is the temperature graph sigmoidal in simple distillation of components with very different bps?

I'm writing an organic chemistry lab report on distillation and I thought I understood this, but the more I look at my lab textbook, I realize I don't. My textbook 1 explains that the temperature of ...
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Strange Distillation Behavior

I was attempting a fractional distillation with 1mL water and 1mL propylene glycol, and I’ve been encountering strange behavior with the heating of the mixture. The heating curve shows strange “spikes”...
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Driving force in distillation

If the pressure is lowered in a distillation column, then the equilibrium curve will move further away from the diagonal (bulge out more) in an equilibrium diagram. This leads to a decrease in ideal ...
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when using glass to glass stoppers, is it best to have them dry or use lubricant?

I have some glass flasks that have glass stoppers. It’s basically the typical glass stopper with the frosted tip which fits into a glass opening. Basically think of a typical glass volumetric flask. i ...
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Is the width of a Soxhlet Condenser Inherent to its Function?

Soxhlet extractors are often coupled to a specifically designed condenser with a very large lower joint. Is this inherent to it's function as a condenser in the apparatus or only because the Soxhlet ...
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Laboratory setup for the distillation of sulfuric acid

Purification of Laboratory Chemicals, 5th Edition, by Armarego, reads (p. 53): Reagents such as water, ammonia, hydrochloric acid, nitric acid, perchloric acid, and sulfuric acid can be purified via ...
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Distilling milligram quantities of oil like it's late 1970s

In a currently retracted* manuscript by Tomas Hudlicky [1, Retraction Watch] the following has been noted: Fifty years ago professors took an active part in all laboratory instructions and they ...
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can i use an isobutane stove (like jetboil) or butane blowtorch with borosilicate glass?

I don't have a bunsen burner, but have a camping stove (similar to https://www.amazon.com/Stansport-183-B-Isobutane-Backpack-Stove/dp/B004EPWM5S) and a blow torch. I'd like to do some distillation ...
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When exactly does the first drop of distillate appear in a distillation?

The below image (source: here) is from a fractional distillation of a mixture of two liquids, one with a boiling point of 69 degrees celsius and the other with a boiling point of 98 degrees celsius. ...
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Reason for rounded fitting at the top end of Allihn Condenser

I am purchasing an essential oil distillation setup. The Allihn Condenser at the top end, and the attached glassware, are rounded. It is supposedly 24/40. I have never seen this. If one of them broke, ...
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Why is the composition of a liquified vapor the same as that of the vapor?

In Organic Chemistry Lab Techniques (Nichols), I found this diagram. I understand that when going from Point $a$ to Point $b$, the composition becomes richer in the more volatile component (component ...
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How to handle CO2 being evolved during vacuum distillation?

Setup: vacuum aspirator pump, distillation apparatus with stirring (instead of a bubbler). Partial vacuum around 5" Hg. What would you suggest to hold the vacuum set-point?
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Why does adding salt to water help distillation?

I've been looking at instructions on how to get lanolin from fleece and a lot of the instructions mention that adding salt to the water before distillation will increase the lanolin yield. Why is this?...
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Azeotropic Distillation - Am I interpreting this VLE diagram correctly?

I've been looking at ways to re-concentrate a formic acid-water binary mixture with the VLE diagram below. Am I correct in saying that to concentrate a solution of say , 40% formic acid by weight I ...
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Distillation of methanol and water - Temperature Change

We tried the synthesis of methyl benzoate in the lab via the Fischer Esterification reaction with excess starting methanol. After 1 hour of refluxing the reactants we immediately set up a simple ...
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Does the distillation of alcohol cause the fractioning of isotopes and carbon-12 enrichment?

In water, distillation causes fractioning of the $\ce{^{18}O}/\ce{^{16}O}$ oxygen isotopes (Wikipedia). Does something similar happen to the $\ce{^{13}C}/\ce{^{12}C}$ and possibly $\ce{^{14}C}$ ...
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Distillation of oxalyl chloride

May I use water as a condensing medium while distilling out oxalyl chloride? As oxalyl chloride reacts with water and the products are $\ce{HCl},$ $\ce{CO}$ and $\ce{CO2},$ when there is a leak or ...
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When to use chromatographic separation vs vacuum-assisted rectification distillation?

I'm trying to understand a bit more about industrial scale separation processes. One particular element I'm interested in is the question as to when chromatography (HPLC or Simulated Moving Bed) may ...
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Separation of methanol–water mix in a plate distillation column

I conducted an experiment to separate methanol and water. I am trying to determine the mole fraction of the distillate collected but having a little trouble with the calculation. The flow rate was $\...
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Will there be some ethanol evaporating before the boiling point of azeotrope? And will it bring some water with it because of the hydrogen bond?

Before the specific temperature, even if the temperature doesn't reach the boiling point of azeotrope or ethanol or water, we know that there are still some ethanol evaporate. In this time(before the ...
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Will distillation do the job of purifying the water?

I asked about my sophisticated water purification system for a generation ship on Worldbuilding Stack Exchange, and somebody mentioned this: If you're gonna go to all the trouble of distilling it, ...
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Separate less volatile component from distilling a mixture [closed]

Is it a strict rule that when we boil a mixture of two liquids, with one being less volatile than the other, the more volatile vapour has to form the greater portion of the total vapours? If it is so,...
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Can you heat something at alcohol bath?

I have a mixture of $\ce{Et2O},$ $\ce{EtOH}$ and water, and I want to distill off the ether. I am using a water bath so not much water is distilled over, as the boiling water is 100 °C, and the ...
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Glass joint stuck in flask

I am doing distillation using system of glassware including a flask and a glass joint. Recently I've faced a problem: the glass joint stuck in the flask. I tried to remove it but it broke and hurted ...
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Why does steam distillation work?

I'm aware that there is a similar question here but it didn't really answer my specific questions. I understand that steam distillation is used to separate an insoluble liquid from an aqueous solution,...
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What are the components of a labware setup for short-path distillation?

I've recently become interested in short-path distillation and have found that most kits are in the thousands of dollars. So I thought that I would compile the labware myself. I understand the theory ...
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Can I determine purity of isopropanol with a hydrometer?

Assuming I start with a known 99.8% purity of isopropanol, after recovery with a distillation apparatus, could I use a hydrometer to test for water content? If so, is there a special one I should use?
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Is there a way to form only ortho product without using fractional distillation?

Using benzene and ethane as your only source of carbon in the final molecule, synthesize the following using any useful reagents. Reaction must form pure ortho compound. I have to form the product ...
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Is 99% Isopropyl Alcohol sold in stores really 99%?

My understanding is that an azeotropic mixture of isopropanol and water is 91%. This makes sense as to why there are so many brands of rubbing alcohol sold at 91%. There are also some sold as 99%, ...
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At what position in the distillation apparatus does the temperature match the boiling point of the distilled substance?

A student is separating $\ce{CHCl3}$ (bp = $\pu{61 ^{\circ}C}$) from $\ce{CHCl2CHCl2}$ (bp = $\pu{146 ^{\circ}C}$) by distillation. She has just begun to collect the first distillate in the receiving ...