Separation Of Ethanol By Pervaporation : Recent Developments

The objective of this experiment was to test the effect of a specialized type of diffusion called osmosis, “which involves in selective transport of water molecules across a selectively permeable membrane” (Lab Manual 2nd edition). It was hypothesized that osmosis will occur when there is an uneven distribution of solute in a solvent. The more abundant the solute is in solvent, the higher the rate of osmosis through the diffusion gradient forming a hypertonic or hypotonic solution. Solvent with equal or no solute forms an isotonic solution. Throughout this lab, data was collected and compiled to analyze these effects across selectively permeable membranes. The results indicated that the water molecules indeed move from

14 mL of 9 M H2SO4 was added to the separatory funnel and the mixture was shaken. The layers were given a small amount of time to separate. The remaining n-butyl alcohol was extracted by the H2SO4 solution therefore, there was only one organic top layer. The lower aqueous layer was drained and discarded. 14 mL of H2O was added to the separatory funnel. A stopper was placed on the separatory funnel and it was shaken while being vented occasionally. The layers separated and the lower layer which contained the n-butyl bromide was drained into a smaller beaker. The aqueous layer was then discarded after ensuring that the correct layer had been saved by completing the "water drop test" (adding a drop of water to the drained liquid and if the water dissolves, it confirms that it is an aqueous layer). The alkyl halide was then returned to the separatory funnel. 14 mL of saturated aqeous sodium bicarbonate was added a little at a time while the separatory funnel was being swirled. A stopper was placed on the funnel and it was shaken for 1 minute while being vented frequently to relieve any pressure that was being produced. The lower alkyl halide layer was drained into a dry Erlenmeyer flask and 1.0 g of anhydrous calcium chloride was added to dry the solution. A stopper was placed on the Erlenmeyer flask and the contents were swirled until the liquid was clear. For the distillation

Prediction: By exposing a membrane to a solvent, ethanol, it will increase its permeability. So the higher the concentration of the solvent, the more permeable the membrane will be. But if the concentration of the ethanol is beyond a certain limit, it may break down the cell membrane to the point where there is in fact no overall effect as the ethanol would disturb the lipids in the membrane.

Method: Distillation is based on the fact that the matter can exist in three phases - - solid, liquid and gas. As the temperature of a pure substance is increased, it passes through these phases, making a transition at a specific temperature from solid to liquid (melting point--mp) and then at a higher temperature from liquid to gas (boiling point--bp). Distillation involves evaporating a liquid into a gas phase, then condensing the gas back into a liquid and collecting the liquid in a clean receiver. Substances that have a higher boiling point than the desired material will not distill at the

The objective of this experiment is to develop an understanding of the molecular basis of diffusion and osmosis and its physiological importance. Students will analyze how solute size and concentration affect diffusion across semi-permeable membranes and how these processes affect water potential. Students will also calculate water potential of plant cells.

In order to assimilate diffusion through a permeable membrane potassium permanganate and methylene blue were used in experiment. The objective was to compare the rates at which the liquid compound of different molecular weight diffused through agar. This was achieved by obtaining agar in a petri dish with two wells to hold the liquid compounds. The rate was measured by time and diameter distance diffused. This process was observed for 60 minutes at 15 minute intervals.

Simple distillation is a separation technique which can be used to separate and purify distillates from a liquid mixture which ideally contains one volatile and one non-volatile compound. If such ideal conditions are not possible—as is usually the case—then simple distillation can be applied as long as the liquid in question is composed of compounds that differ in volatility such that their boiling points differ by at least 40 to 50 degrees Celsius. Because

Distillation is a method of separating two volatile chemicals on the basis of their differing boiling points. During this lab, students were given 30 mL of an unknown solution containing two colorless chemicals. Because the chemicals may have had a relatively close boiling point, we had to employ a fractional distillation over a simple distillation. By adding a fractionating column between the boiling flask and the condenser, we were able to separate the liquids more efficiently due to the fact that more volatile liquids tend to push towards the top of the fractionating column, thereby leaving the liquid with the lower boiling point towards the bottom. After obtaining the distillates, we utilized a gas chromatograph in order to analyze the volatile substances in the gas phase and determine their composition percentage of the initial solution. Overall, through this lab we were able to enhance our knowledge on the practical utilization of chemical theories, and thus also demonstrated technical fluency involving the equipment.

The purpose of this experiment was to separate a two component mixture using fractional distillation. Distillation is a process of vaporization than condensation of a substance, used primarily to separate substances from a mixture when there are different boiling points. Fractional distillation is when the mixture has multiple substances with similar boiling points, and a fractional column is used to create multiple vaporization/condensation cycles. Fractional distillation is important when two or more substances need to be separated, but they have similar boiling points.

Cell membrane is a selective boundary composed of a unique phospholipid bi-layer structure consisting of lipids, proteins and carbohydrates. This structure regulates the import and export to maintain homeostasis condition inside the cell. (Knox et al., 2014) The plasma membrane is referred as a fluid mosaic which also has selective permeability. The permeability of the membrane can be varied depending on the external conditions. (Mitchel, 2015)

Ethanol is an alcohol product produced from corn, sorghum, potatoes, wheat, sugar cane, even biomass such as cornstalks and vegetable waste. When combined with gasoline, it increases octane levels while also promoting more complete fuel burning that reduces harmful tailpipe emissions such as carbon monoxide and hydrocarbons. There are two processes for making ethanol: wet milling and dry milling. Many other fuel sources are made through a chemical process called. Many forms of biofuel have definite environmental advantages over petroleum-based gasoline and diesel fuel. However Ethanol contains 35% oxygen. By having more oxygen in fuel, it reduces the harmful tailpipe emissions. Ethanol also displaces the use of toxic gasoline components such

The permeability of membranes can be altered in several ways. From previous preliminary work I know that reagents, for example detergents and alcohol alter the arrangement of the phospholipids in the membrane allowing substances to leak out of the cell. Temperature also affects the membrane. As membranes relay on protein molecules to allow molecules to enter and leave the cell through facilitated diffusion the temperature must not exceed the approximate temperature of 50°C as at roughly this temperature proteins are denatured. This is due to an increase in kinetic energy making atoms in the protein to vibrate more; this breaks hydrogen and ionic bonds. These proteins

Since the advent of membrane contactors as means of separation alternative to conventional techniques of separation, such as distillation towers, packed bed towers, research has been done on membranes so as to industrialize the whole process for large plants. The membrane contactors provide significant advantage over the more traditional separation tools and hence, are being increasingly used. The researchers have, though, realized a major disadvantage associated with membrane contactors. The membrane used for liquid-gas or liquid-liquid contact undergoes a phenomenon, referred to as wetting, which primarily involves the liquid entering the pores of the membrane in the gas-liquid separation (or either of the two liquids in the case

Transport conditions: Feed phase: citric acid 10-2 M, pH 2-12. Stripping phase: deionized water, pH=6.8. Membrane: 12.60 cm2 of surface area, Calix[4]resorcinarene (0.15 g/g mixture of polymers), 0.03 ml 2-NPOE/g mixture of polymers. Values obtained after 5 days of experimentation.

An alcohol bath was prepared with an ethanol solution and dry ice, the solution was measured using a thermometer, at approximately -15˚ the bath was placed under a Polaroid filter and above a stable jar upon a white piece of paper. The capillary level holder with the frozen capillary tubes was placed carefully into the bath (at an angle to reduce effervescence). A lamp was placed 20 cm away from the setup and shone on the Polaroid filter. This setup ensured the ethanol solution didn’t heat up too rapidly.