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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Fractional Distillation Question
We're covering fractional distillation in my physical chemistry class. I'm confused regarding this diagram:
From your starting point, you heat the binary mixture (in this case benzene and toluene) to ...
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How can I read an Anschütz/Bennert manometer and how can I make sense of it?
Recently I have come across a mercury-filled manometer for vacuum distillation that somewhat resembles a U-tube shaped manometer, but with one arm sealed and completely filled with mercury. Searching ...
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Fractional Distillation Fractions
Currently, I am trying to remember the order of fractions within the fractionating column. However, I have found a contradiction.
Consider the above diagrams, both from reputable sources. The first ...
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Distillation of free fatty acid from soya acid oil
I have soya acid oil with FFA percentage of about 40. After degumming and glycerolysis I am able to bring down the FFA percentage to 5. It does go down to about 2 percentage but it takes an enormous ...
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Why does brandy have a higher methanol-to-ethanol ratio than beer, despite the distillation?
From my googling, beer tends to contain around 16mg/L of methanol. While for brandy, typical methanol content is around 1000mg/L (give or take a factor of 3, depending) The distillation that brandy ...
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Organic solvents distillation for purification
I've realised that the majority of the solvent that we use in my lab are contaminated with grease (peaks at 1.26 and 0.86 ppm in $^1H$ NMR in $CDCl_3$), since they come in plastic containers (I guess ...
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NMR and dienes to isolate certain isotopes?
I am looking to achieve isotope separation using transition states.
In the rxn of dienes with halogens, based on the temperature, the dienes can create a thermodynamic product or a kinetic product. ...
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Vacuum distillation of azeotropic mixtures
I was wondering if vacuum distillation can seperate azeotropic mixtures.
Consider the ethanol/water system. At 95.6% ethanol content, the system forms an azeotrope because the vapor composition ...
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Is there some other way to perform fractional distillation without using Vigreux Column?
So recently I was performing an esterification reaction of oils like peanut oil or any neutral oil where I got some products which are only possible to filter using fractional distillation. I already ...
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"Cleaning" of HNO3 solution using distillation
In many industries, pickling baths are common. These are 10 cubic meter baths containing acid baths that metal components are dipped into prior to surface treatment. When the metals are dipped, some ...
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What is the difference between distillation temperature and boiling point?
Is there a difference between the distillation temperature and the boiling point of a fluid, in my case kerosene? And if there is, what is the difference?
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Destination of carbonyl compounds free toluene
I am currently in the process of trying to get toluene free of carbonyl compounds using a distillation processes with DNPH.
Unfortunately I am no distillation expert. And am running into some problems....
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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 example, 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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