What are the steps in purification by extraction using organic solvents?
611075
I'm assuming you are extracting from an aqueous solvent?  Preferably, you want to increase the polarity of the aqueous solution, such that the solute has less affinity for water than it would for the organic solvent.  This can be done by "salting" the water (increasing the ionic strength by adding an inert salt, a la NaCl).  You then extract the solute with your organic solvent of choice, usually using smaller aliqouts more frequently vs. larger aliqouts (deals with partition coefficient, or how much will get extracted vs. how much remains in the water).  After extraction, the organic solution is usually dried (more often than not by MgSO4 or Na2SO4) and then the solvent is distilled off to yield hopefully pure product.
139382
First, you dissolve your compound in the solvent in which is is most soluable (perhaps THF or methylene chloride).  Then you very carefully use a pipette to layer the solvent in which it is not soluable on top (perhaps diethyl ether or pentane).  You need to add the second solvent slowly and carefully.  Let the solvent run down the side of the container.  Obviously the top solvent needs to be less dense than the bottom one.  You then let the container sit undisturbed on the bench or in the freezer away from any vibrations until crystals form.  As the upper solvent diffuses into the lower solvent, you compound will become less soluable until it falls out.  The first solution should be as close to saturated as possible.
795210
When choosing a recrystallizing solvent you want a liquid that:\n\n1. Does Not React with what your trying to recrystallize.\n\n2. A solvent that the compound is barely soluble in. \n\n3. A solvent that quickly evaporates.\n\n    After you determine your solvent you can dissolve your compound without changing it. You can add just enough solvent to dissolve the compoud. Wait for the solvent to evaporate causing the ppt of your purified compound.\n\nMark
729891
sugar is more soluble in organic solvents like acetone than salt. we can exploit this phenomenon to effect a separation. though complete separation may be achieved by crystallisation or precipitation.
724749
sorry i dont really know, but a kit designed for extraction might work o.k. I'm guessing that you have tried regular high salt or phenol based methods and these have not been successful, perhaps repeating the extraction protocol on the resulting product may help.\n\nhad to laugh at the above answer, clearly has no idea but has got the hang of copy and paste!
303081
Purify it. And then have it in a closed system where nothing can get to it
585025
I don't know that you can, different solvents react differently to pressure, so I don't think it's a one eqaution fits all kind of process.  That's why they all have different graphs for phase vs temperature/pressure.  I'm sorry.\nSounds like you have a pretty high boiling point though, the things I've taken off that had to be real high temp were water, toluene, and pyridine.  Could it be one of them?  They smell pretty different, so you'd know which.  \nThat's an interesting question though, I've never stripped a solvent that I didn't know what it was.
366491
different ways to do it.  steam distillation, expression, solvent extraction and efleurage. the first is the easiest and what you want to know if you are looking for a how to. Use hot steam, like a steamer, you'll end up with the oil and water.  then separate the oil.  \n\nthe other methods are more complicated, but you do end up with more oil.  but at what price?  second method the is to use pressure or centrifugation. At home, not likely you have anything to make this work.   The third method you use a solvent, but then the oil and solvent are mixed.  You then evaporate the solvent (you can get at a whole foods store to do this) when the solvent is evaporated you are left with a heavy, waxy substance called concrete. Then you have to separate the liquid from the was.  it's great because it is most concentrated from of aroma, but very time consuming and complicated.  That last, efleurage is a really long process using animal fats and alcohol. Although essential oils main usage is in cosmetics and perfumery, many of them do have proved therapeutic properties.
196696
One possibility is fractional distillation.  This procedure takes the boiling points of each component of a mixture into account.  The mixture is connected to the proper apparatus and placed over heat.  That component with the lower boiling point will evaporate off first and can be collected in a recovery flask.  That material with a higher boiling point will evaporate latest.
842976
20 grams\ndissolving compounds and then driving of the solvent is a common way to purify a compound. You will not lose any of the compound unless it is reactive with the solvent you dissolve it in. In the case of water and salt they are not reactive so when you drive off the water you will be left with the same amount of salt that you started with.
388432
The separation of normal paraffins from isoparaffins is done commercially for a number of reasons. In the lighter hydrocarbon range, isoparaffins are often more desirable because of their higher octane values and their superior gasoline alkylation characteristics. In the heavier range, normal paraffins are typically the desired product because of the benefits derived from their linearity in the production of plasticizers, linear alkylbenzene sul-fonates, detergent alcohols, and ethoxylates.\n\nThe specific application of the UOP* Molex* process to the separation of normal paraffins from isoparaffins. Although not limited in its application to a particular processing mode or carbon number, the Molex process is most often used in the recovery of normal paraffins for plasticizer and detergent-range applications. Typical carbon numbers are C6 to C10 for plasticizers, C10 to C14 for linear alkylbenzenes, and C10 to C18 + for detergent alcohols.\n\nThe UOP Molex process is an established, commercially proven method for the liquid-phase adsorptive separation of normal paraffins from isoparaffins and cycloparaffins using the UOP Sorbex* separations technology (see Chap. 10.3), which uses zeolitic adsorbents. Isothermal liquid-phase operation facilitates the processing of heavy and broad-range feedstocks. Vapor-phase operations, in addition to having considerable heating and cooling requirements, require large variations of temperature or pressure or both through the adsorption-desorption cycle to make an effective separation. Vapor-phase operations also tend to leave a certain residual level of coke on the adsorbent, which must then be regenerated on a cyclic basis. Operation in the liquid phase allows for uninterrupted continuous operation over many years without regenerations.\n\nRefer to Chap. 10.3 for details of the operation of this separations technology. Figure 10.7.1 illustrates the general design characteristics of such units.
999393
Most common method would be an oxidative digestion (most likely using ultraviolet radiation) in order to eliminate the organic matrix, and subsequent simultaneous ICP-OES analytics. Numerous other detection methods are available (electrochemistry, mass spectroscopy, atom absorption spectroscopy, even classical wet chemistry might give satisfactory results if done with extreme care and insight).\n\nThe heavy metals would be the usual suspects also monitored in drinking water, with special emphasis on any material used or present as impurity in the packaging (tin, lead, cadmium, zinc...)
849149
Sure.  Any element can be purified.\n\nNitrogen is fairly easy.  All you have to do is liquify air and let the oxygen and other gases boil off at higher temperatures.  Just reduce the liquid down to around 75 degrees Kelvin.  Water vapor, CO2, and Nitrogen oxides will form solids, which you can decant the liquid from.  Then raise the temperature to about 78 degrees and the nitrogen will boil off (at 77.K, -196C), leaving oxygen which boils at 13 degrees higher.  Collect the gas, nitrogen, that boils off.  If you need to make it even purer, repeat the separation process with the "pure" nitrogen.
867130
You need to buy or create a detergent lysis buffer. Something with, say, Triton X-100 or Igepal and a protease inhibitor cocktail.\n\nYou can buy these ready made or find several recipes quite easily in standard methods textbooks.\n\nOnce you've isolated your cells you need to incubate them on ice with your lysis buffer then macerate the cells using either a vortex or Dounce homogenizer. Spin down the mixture at high speed and the supernatant is your crude whole cell extract.
592402
I agree with the first poster on C and E, but I'm not sure if A is also.  A solute dissolving in a solvent seems like a chemical process to me, but I don't remember for sure.
883855
The samples must be homogenously ground to enable the solvent to fully soak into the sample and extract the compound you want in question. Also there is a question of statical averages so a uniformed powder sample is the best for this process. If the sample is lumply or too big the solvent can't fully soak into it and wherefor not all of your compound in question is extracted by the process (Then the solvent fills up the soxhlet thumbie (sp)). If this happens you will get a incorrect value then you come to do the maths in determinating the amoult of the coumpound in question.
722185
From this patent\n\nwww.freepatentsonline.com/6962719.html\n\n\n\nThe total extract described in EXAMPLE 1 was loaded in a dialysis bag with molecular weight cut off 500 (Spectra/Por®, Cat. No. 131 057). Both ends of the bag were sealed with clamps. The bag was placed in a bucket contained deionized water, in which the ratio of the supernatant and deionized water was 1:10. The total extract was dialyzed at 4° C. with stirring thrice each for 20 hours. The solution remaining in dialysis bag was collected and concentrated under reduced pressure to give the extract.