Lab Experiment : Fractional And Simple Distillation

Solubility refers to the ability of a solute to dissociate in a solvent. In the case that a solute does not dissociate in a solvent, we would state that the compound is insoluble (4). Extraction signifies separating two different substances when mixed together; typically, these substances consist of an organic layer and an aqueous layer (1). In this experiment, several solutes including Benzophenone, Biphenyl, 1-Octanol, 1-Butanol, Methyl Alcohol, and Dichloromethane (DCM) were placed in different solvents such as water and hexane to determine the solubility of each solute when placed in various polar and non-polar solvents. There will be successful dissociation whenever a solute and a solvent are both classified as either polar or non-polar. If a nonpolar solute is placed in a polar solvent, there will not be dissociation, and vice versa. Extraction techniques were performed using a separatory funnel to determine the amount of solute (caffeine, benzoic acid, sodium benzoate, and an unknown) that was extracted after being placed in DCM and evaporated. The extraction procedures should be successful due to the role solubility plays with each solute in DCM (2).

The process of extraction removes a desired compound from a mixture. Because molecules with similar intermolecular forces are more soluble in one another, organic compounds are usually dissolved in organic solvents. Based on the solubility differences of the organic solution and water, when mixed, two distinct layers form. Sometimes, small amounts of the solvent may dissolve in water. To prevent contamination of the product, a drying agent is added to absorb the water molecule. The organic solvent is evaporated from the organic compound through the use of a rotary evaporator. It is a quick process that reduces the pressure and thus the boiling point of a liquid. In this experiment, eugenol was separated from mixtures containing methylene chloride and hexane. If was predicted that methylene chloride would be the most effective solvents due to its immiscibility to water and low boiling point.

Abstract The purpose of this experiment is to separate a mixture of hexane and toluene by collecting fractions through simple and fractional distillation. Because hexane’s boiling point is about 68°C and the boiling point of toluene is 111°C, the two compounds distill at different times. Pure products will be analyzed with gas chromatography to determine the success of the distillation. For easy separations, a simple distillation apparatus probably will suffice, but for more difficult separations, a fractional distillation apparatus will be used in this lab. The goal is to show that fractional distillation separates the two compounds more completely because less material is lost. In conclusion the fractional distillation indeed separates the two compound

Whereas for simple distillation, the compounds need to be around 80C apart in order for proper separation to occur. Thus, cyclohexane and toluene were not able to be properly separated since the boiling point for cyclohexane was 80.74C while the boiling point of toluene was 110.6C—there two boiling points are fairly close to one another. Thus, the mole fraction for cyclohexane and toluene were fairly low when compared to cyclohexane and

These layers can be separated through the use of a seperatory funnel which drains the bottom layer into a separate container. This method uses the understanding of partition ratios of solutes to different paired solvents to produce an equilibrium leaning towards one solvent over another, thereby extracting a compound from one liquid to the other (Padias 128-37). For example, consider a mixture containing two solutes, solute A and solute B, and two immiscible solvents, solvent A and solvent B. If solute A dissolves well into solvent A, but not very well into solvent B, and solute B dissolves well into solvent B but not very well into solvent A, there would be a higher ratio of solute A in solvent A than in solvent B, and a higher ratio of solute B into solvent B than in solvent A. One can then see that, through the use of different solvents, two dissolved solutes can be separated from a mixture. This ratio of a solute concentration to different solvents is defined by K, the distribution constant. Successive filtrations yield’s a higher percentage of products.

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

Objective: The main goal of this lab is to learn how separation of binary liquid mixtures is performed. Especially when the two liquids have boiling points varying by about 30° C. Hexane can be separated from toluene in this experiment because of the difference in their boiling points. Since toluene has a higher boiling point, it will left at the bottom while the hexane starts to boil out and collect in the Hickman still. GC measurements help us in determining how accurate our data is by making a graph of the amount of hexane and toluene in each fraction. Also this lab gives experience with semi-micro

This experiment was done in order to understand both fractional distillations and gas chromatography. In addition, this experiment was done to separate and identify two liquids that made up an unknown mixture. Gas chromatography was used to figure out the ratio of these two liquids.

Simple distillation is more effective when the two components of a mixture have a difference in boiling point that is greater than 50°C. This large difference makes the need for theoretical plates non-existent since there is no need for multiple distillations per fraction. We can collect all necessary data from a simple distillation fraction using a gas chromatograph. The gas chromatograph vaporizes the injected sample and it begins to undergo partitioning. It is pushed into a small heated column that is coated in the liquid form of the sample. The longer the substance stays inside the column before passing over the heated wire, the longer the retention time is. The retention time is utilized to identify the substance, while the number of peaks shows how many substances are present, and the size of the peaks show how much percentage each substance occupies in a sample. The intrinsic properties of isopropyl acetate and toluene allow analysis of the provided data to become quite simple. Isopropyl acetate has a lower boiling point because it has a relatively low dipole moment and only one double bond. Thus, the intermolecular forces are relatively low in isopropyl acetate leading to a low boiling point. Toluene has a higher boiling point because the methyl group, attached to the benzene

With the purpose of the experiment being to identify the 30 mL of unknown liquid, the theoretical basis of simple and fractional distillation must be deconstructed and applied to the data obtained describing the liquid in question.

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.

A 5.34% error is very low, this means that 95% of what is theoretically possible to distill from this mixture was actually collected when performing the experiment. The apparatus used for the distillation involved having the thermometer in a silicone pocket. This is due to the fact that silicone improves thermal conductivity rather than just having the thermometer in the air or in the mixture of water and propanol. Silicone has a thermal conductivity of 0.1 compared to 0.58 of water [4].

Steam distillation is a process used often in chemistry to extract a particular component of a mixture at a temperature above the temperature where the substance starts to degrade. As a homogeneous mixture is cooled while being exposed to a component in gaseous form, the partial pressures of the parts (hypothetical pressure of a gas if it had the same volume as the total volume at the same temperature) increases over time. Extraction can occur when the sum of the partial pressures is greater than the atmospheric pressure.

The membrane distillation process offers some benefits compared to other separation processes [ Pangarkar et al., 2011, Alcheikhhamdon et al., 2015](4):