Questions tagged [separation-techniques]
For questions about the separation of mixtures and solutions into pure compounds
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Would it be possible to separate and identify plastic compounds/mixtures?
In the lab I have been trying to identify and quantify the ratios of different components of sampled plastic compounds.
The ingredients are generally known:
Polymer matrix (PE or PP)
Pigments (...
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How viable is production of magnesium oxide and sulfuric acid from Epsom salt?
Epsom salt $(\ce{MgSO4})$ is really cheap (less than 0.5 €/kg), whereas $98\,\%$ or better grade magnesia $(\ce{MgO})$ is much more expensive (3 to 4 €/kg).
Is it possible to convert magnesium sulfate ...
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Which process would separate the mixture of toluene, cyclohexane and water?
I think that answer would be:
Toluene and cyclohexane do not dissolve in water (since they are nonpolar), so I would first separate the water from the mixture with a separator funnel.
A mixture of ...
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Can I separate paint thinner into acetone and toluene by simply boiling it?
I have a paint thinner that contains 60% toluene and 40% acetone. I would like to obtain some more-or-less pure toluene. Considering the big difference in boiling points (110°C toluene vs 56°C acetone)...
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How to separate the salts within homemade sea salt
Goals
There are a few things that I'm looking to do:
Separate salt from seawater via some evaporation technique.
Separate the each of the major salts from the resulting sea water to get each into ...
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What is the correct unit of a RI detector used for HPLC analysis?
I analyze sugar compounds in soft drinks with HPLC using refractive index detection (RID) on Agilent 1260 Infinity Binary LC (System User Guide (PDF)). I am not sure which unit to put next to the $y$-...
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Is it possible to separate $\ce{CO2}$ from exhaled air? How?
Just for fun, I would like to see if I could make my own concentrated $\ce{CO2}$ by separating it from my own exhaled breath. I would also love to see if I could pressurize it so I could make my own ...
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How to separate a mixture of sodium chloride and sodium hydroxide?
I recently did a double displacement reaction in which I formed a solution of water with sodium hydroxide and sodium chloride dissolved in it. Now I want to separate both of them. How can I do this?
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How do we separate H2O from CO2? [closed]
Let's say I have a mixture of $\ce{CO2}$ and $\ce{H2O}$ gases. I've read that $\ce{CO2}$ is heavier (molar mass is $\pu{44.01 g/mol}$) than $\ce{H2O}$ (molar mass is $\pu{18.02 g/mol}$). So, if the ...
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What matters for ion exchange: net or local charge?
I am interested in separating two small organic molecules by ion exchange chromatography.
Following the example set by several old papers for these molecules, I want to use a cation exchanger. Both ...
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Is Silica Gel fit for Ultra-High Dessication?
I had the (perhaps wrong) notion that silica gel wasn't that strong of a dessicant, especially compared to CaO, MgO, CaSO4, H2SO4, KOH, Mg(ClO4)2), but I've been exposed to information* that might ...
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How to make clean water from urine in a wastewater treatment plant? [closed]
Referring to a video here, describing a filter that treats wastewater, wouldn't urine in the wastewater not get filtered out because a sand filter alone does not separate urine from water? How is ...
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Calculation of the Seperation factor of Ethanol / Water rectification based on two saturated vapor temperatures
I want to calculate the efficacy of a Water / Ethanol rectification based on two temperatures with help of a vapor-liquid equilibration diagram.
The first temperature is measured right above the ...
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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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Why does a big protein move during gel electrophoresis but to a lesses extent through a size exclusion column?
A big protein going through gel electrophoresis will be forced through the gel, it will drift a small way and will show on the top of the gel, while in size exclusion, the big protein is not forced to ...
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Reaction of amines with diethyl oxalate (Hofmann amine separation method)
Why does only one molecule of secondary amine react with diethyl oxalate and two molecules of primary amine react with diethyl oxalate?
I feel secondary amine also should have reacted similar to ...
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How does a freeze-thaw cycle separate a mixture?
Imagine that I defrost a tube of serum (only the yellow stuff, with blood cells removed) standing still and upright in ambient air. I have seen that as it defrosts the sample separates into different ...
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How to remove oil/grease contaminant from an aqueous solution?
I have a solution of water and calcium nitrate that is contaminated with some sort of heavy petroleum oil, semi-solid at room temperature a bit like petroleum jelly, and a strong odor of very crude ...
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What solvent dissolves calcium nitrate but not ammonium nitrate?
I am experimenting with a precipitation reaction between ammonium sulfate solution and calcium nitrate. Calcium sulfate precipitates and can be filtered out easily.
I am wondering if there's a way I ...
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Separation methods [closed]
I put some iron nails in water, and obviously, those started oxidizing, making those hydrogen bubbles. Some days after, the water was orange, indicated that the FeO has just dissolved in it. I found ...
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Why can I extract all metabolites from blood plasma with one solvent, but to extract only fatty acids I must use many solvents?
I want to do a metabolite study using GC- without derivatization and UPLC-MS (RP and NP) on samples of plasma and urine. My hypothesis is agnostic about which metabolite will correlate with the ...
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My particles won’t separate without neutralizing the solution. I want to understand why?
I etched active carbon with a concentrated KOH solution and added HCl to neutralize the KOH. Separeted the particles with centrifuge at 4000 rpm. They should be micron sized.
My boss asked me to stop ...
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How do I separate an Indium-Gallium alloy into Indium and Gallium?
I've recently learned more about Indium and Gallium, and I find them quite interesting, especially how an alloy can be manually made simply by rubbing them together. I'm curious though, is there a ...
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Has anyone added dyes to a mixture about to separated by chromatography in order to visualize where the desired product lies?
Usually in preparative chromatography one needs to know when the desired substance to be separated is coming down the pike. Often this required some sophisticated instrumentation. But, it occurred to ...
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How to adjust selectivity of gas-permeable PDMS membranes for environmental applications?
I have an idea about making an environmental sensor that uses a gas-permeable membrane (GMP) and how its probe could be submerged in a water source with an off the shelf gas sensor.
So far, my ...
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What is the function of thin layer in thin layer chromatography?
I just learned about the thin layer chromatography, which I think is basically the same as the paper chromatography.
I am wondering what is the function of the thin layer? I mean, what's special about ...
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How to separate manganese(IV) oxide and chromium(III) hydroxide?
I am trying to find a reagent that keeps either $\ce{MnO2}$ or $\ce{Cr(OH)3}$ solid and make other soluble so I can centrifuge or use filtration. I thought of $\ce{NaOH},$ but I could not find any ...
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What is the principle of “scrubbing” in liquid extraction or solvent extraction?
There are many steps in solvent extraction:
Extraction
Scrubbing
Back extraction
I understand the 1st and the 3rd.
What is the principle of scrubbing?
Is it just washing the organic phase?
How ...
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How are Silanol groups functionalized unto mesoporous silica structures?
As described in this research paper:
Immobilization of Jacobsen type catalysts on modified silica, Jairo Cubillos , Edwing Grajales, Santiago Vásquez, Consuelo Montes de Correa, Rev. Fac. Ing. Univ. ...
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How do you separate microcrystalline cellulose from amino acids in a powder mixture?
I am looking to separate out the microcrystalline cellulose that has been mixed in with amino acids in a powder mixture.
I have tried suspending the powder mixture in water and then filtering out the ...
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How do I get calcium citrate to precipitate in experiment on extraction of citric acid from juice?
I was planning to extract citric acid from mango juice by first using Aspergillus niger fungus by fermentation to convert the mango juice to citric acid, then extracting by first adding sodium ...
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Method of separating product and conserving the catalyst
I'm looking for a way to separate reaction product of iodobenzene with ethyl 2-methyl-3-oxopentanoate in 1,4-dioxane (toluene is an alternative as a solvent). The catalyst being used is $\ce{Pd2(DBA)3}...
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How to separate Cu and Ni from alloy containing different metals such as Al, Cu, Ni, (Zn, Pb, Sn < 5%)?
I have an alloy containing different metals such as Al, Cu, Ni, (Zn, Pb, Sn, Ag, Si in small amount < 5%). How can I separate Cu and Ni from this alloy?
I tried to dissolve alloy in sulfuric acid, ...
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How to remove sugar from juice
My son has autism and we noticed that blueberries make him feel much better. The problem is blueberries contain sugars which interfere with diet he has (low carbohydrate).
How do I filter out the ...
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What is the state of stationery phase in paper chromatography?
As per my textbook:
Partition Chromatography: Partition chromatography is based on continuous differential partiotioning of components of a mixture between stationary and mobile phases. Paper ...
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How to choose a proper chromatography method to separate substrates?
I'm a freshman and I recently learned how to do TLC and column chromatography. I also know a little about other ways to separate things by chromatography, such as affinity chromatography, gel ...
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What does all chromatography have in common?
We're learning about chromatography in class, and I'm confused about all the different types (e.g. those that separate liquid-liquid solutions vs. those that separate liquid-solid solutions vs. those ...
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How to store small amounts of gas
I need to store small amounts of gas. I already saw devices that look similar to the image below, but I don't know how they are called. Does someone here know how these devices are called? I am also ...
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How much does oxygen enrichment improve some combustion engines?
This question is about how much the combustion efficiency increases with oxygen enrichment in modern combustion engine designs. A desirable way to answer is to give the fuel efficiency dependency on ...
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Chromatography- why tM is separated from other peaks? [closed]
tM in Chromatography is the time of exist mobile phase. But, the mobile phase exist together with all the compunds that tasted in the process. So, why in the graph of signal to time we can see a peak ...
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Dynamic viscosity of gas mixture (appropriate estimation)
What estimation of the dynamic viscosity $\eta = f(T)$ $([\eta] = \pu{Pa·s})$ of the gas mixture components would you recommend during adsorption at a low temperature, approx. $\pu{293 K}$ to $\pu{333 ...
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are refractometers generic?
I need to check the presence (and also purity approx) of a substance in solution. I have a very good reference (10mg/1ml - the substance in water).
Can I use a refractometer to do this?
I am trying to ...
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How to make acetic acid more volatile so that it can be removed by vigorous aeration of an acetic acid-water mixture? [closed]
I want to remove acetic acid from a mixture of acetic acid and water by aeration. The concentration of acetic acid is 200 ppm (mg/L). The pH of the water is more than 5. I want to reduce the acetic ...
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Purification of Red Phosphorus
The Boring Stuff
I'm well acquainted with various fields of science & engineering, but my foray into the world of chemistry is relatively recent.
I'm in a location (probably most of us are to some ...
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Solubility Product, and it's relation to solubility
In order to remove temporary hardness of water, it is boiled.
On boiling, while Ca(HCO3)2 gives CaCo3(ppt.) , Mg(HCO3)2 gives Mg(OH)2(ppt.).
According to my book precipitation of Mg(OH)2 occurs due to ...
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Ways to determine the concentration of alkyl halides in organic solvents
I have a volatile alkenyl bromide dissolved in hexanes. I have to use the halide in a Grignard reaction but separating it from hexanes is hard (the bromide is light sensitive and very volatile). I ...
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Separating sodium sulfate from chromium trioxide solution
I was looking at the industrial process for the production of chromium trioxide by treating sodium chromate or the corresponding sodium dichromate with sulfuric acid. This results in the formation of ...
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Shea Stearin Extraction by Dry Fractionation
I have been able fractionate palm oil and extract palm stearin using the following method:
Melt the palm oil (over 80 °C)
Keep the melted oil at 33.5 °C for 24 hours (using an immersion circulated ...
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Theoretical plates in Plate theory of chromatography
In "Chromatography theory" by Scott and Cazes,
The plate volume is given as ($v_m+Kv_s$) where $v_m$ and $v_s$ are the volume of stationary and mobile phase in the column and $K$ is the ...
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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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