Literature Survey: Single-Stage Distillation
A single-stage distillation is a separation method whereby a liquid mixture is partially vaporised. The vapour and lingering liquid are in equilibrium in the process and separation take place. Usually, the feed is preheated before entering the separator, during the practical which was conducted the feed was heated in the separator. Due to a difference of the substances’ boiling point, one substance will become a vapour whilst the rest are in a liquid state, then separation occurs. The quantity of vaporisation affects the concentration of the substances in both liquid and vapour phase. (Nptel. ac. in, n. d. )In this particular practical procedure, a mixture of acetone, hexane, ethanol, isopropanol, and char oils were used. A single-stage distillation is also used to recycle the solvent. Recycling solvent through distillation includes the following steps:
- A waste solvent is spent by a distillation vessel.
- Heat is injected into the waste solvent electrically by a thermal oil jacket.
- The vessel is operated under a vacuum, this will decrease the boiling temperature of the solvent.
- When the boiling temperature is reached, the waste solvent changes from liquid to vapour.
- The solvent in vapour phase is clean, it passes through a condenser which has a sub-cooling and condensing section. The solvent changes back the liquid and cooled to ambient temperature.
- The non-volatile liquids do not experience vapour phase, they remain as still bottoms and discharged.
MSDSA material safety data sheet (MSDS) is a procedural document that delivers a detailed and all-inclusive information of a controlled of a specific product. It offers information related to the health effects when one is exposed to the product, the hazard assessment with regards to the use, storage and handling of the product. The MSDS also provides information on measures the user has to take when using the product and it offers emergency procedures. The MSDS places a responsibility on the user of the product, provided the supplier gave accurate information. (Uregina. ca, n. d. )
Acetone
Acetone is one of the most used product in a lab since it is a wash solvent. It is slightly hazardous when it comes to contact with a person’s skin, one must avoid eye contacted, ingestion and inhaling. (Sciencelab. com, 2013) Acetone is flammable and it has an auto-ignition temperature of 465 degrees Celsius with a flammable lower limit of 2. 6% and an upper limit of 12. 8%. In terms of an explosion in the lab, it is a safe product to have in the lab. At sea-level pressure, Acetone a boiling point of 56. 2 degrees Celsius.
Hexane
Hexane is similar to acetone, it is to some extent hazardous when it comes to contact with one’s skin. (Sciencelab. com, 2013) Contact with eyes, ingestion, and inhaling should be avoided. A prolonged exposure may be toxic the peripheral nervous system, skin, central nervous system and may damage organs. Hexane an auto-ignition temperature of 225 degrees Celsius, with a flammable lower limit of 1. 15% and an upper limit of 7. 5%. It is a relatively safe product to work with in terms of fire ignitions and explosions. At atmospheric pressure, the boiling point of Hexane is 68 degrees Celsius.
Ethanol
Ethanol is also referred to as an ethyl alcohol. Just as all other products used in this practical experiment, ethanol is slightly hazardous when it in contact with one’s skin. (Sciencelab. com, 2013) Contact with eye area, inhaling, and ingestion should be avoided always. Ethanol contains a substance mutagenic that is toxic to blood, upper respiratory tract, the reproductive system, skin, liver, and the central nervous system. Repeat exposure to the product may lead to damaged organs. Ethanol has an auto-ignition temperature is 363 degrees Celsius with a flammable lower limit of 3. 3% and an upper limit of 19%. (Liebenberg, 2017) Working with ethanol in a laboratory with room temperature (25 degrees Celsius) is relatively safe.
When combusted it gives off carbon oxides as products. At sea level pressure ethanol has a boiling point of 78. 5 degrees Celsius. Isopropanol Isopropanol’s chemical name is 2-propanol. Concerning safety, it causes slight irritation when it is exposed to an individual’s skin. It is hazardous when inhaled, ingested or come to contact with the eyes. (Sciencelab. com, 2013) The product has a mutagenic substance that may be toxic to the kidneys, skin, liver, and central nervous system. Continuous exposure to this product might damage one’s organs. Isopropanol has an auto-ignition temperature of 399 degrees Celsius with a flammable lower limit of 2% and an upper limit of 12%. (Babec. org, 2001) Combustion with this product will result in the production of carbon oxides. At atmospheric pressure, isopropanol has a boiling point of 82. 5 degrees Celsius.