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we will discuss the difference between absorption and stripping in details.
Absorption
Absorption is a process by which a solute is transferred from a gas phase to a liquid phase. This process involves the use of a solvent to dissolve the solute from the gas phase into the liquid phase. The solvent used for absorption is chosen based on its ability to dissolve the solute of interest and its physical and chemical properties. The gas and liquid phases are brought into contact with each other, and the solute is transferred from the gas phase to the liquid phase by diffusion.
Absorption is often used to remove pollutants or unwanted components from gas streams. For example, carbon dioxide can be removed from flue gases using absorption with a solvent such as monoethanolamine. Similarly, water vapor can be removed from air using absorption with a desiccant such as silica gel.
The efficiency of absorption depends on several factors, including the solubility of the solute in the solvent, the surface area of contact between the gas and liquid phases, and the concentration gradient of the solute across the gas-liquid interface. The absorption process can be enhanced by increasing the surface area of contact between the two phases, increasing the concentration of the solute in the gas phase, and reducing the thickness of the gas-liquid interface.
Stripping
Stripping is a process by which a solute is transferred from a liquid phase to a gas phase. This process involves the use of a gas stream to remove the solute from the liquid phase. The gas used for stripping is chosen based on its ability to absorb the solute of interest and its physical and chemical properties. The liquid and gas phases are brought into contact with each other, and the solute is transferred from the liquid phase to the gas phase by diffusion.
Striping in distillation column
Striping in a distillation column refers to a phenomenon in which the liquid being distilled is not evenly distributed across the column. This can occur for a variety of reasons, including differences in temperature, pressure, and flow rate throughout the column.When striping occurs, certain sections of the column may become overloaded with liquid, while other sections may be relatively dry. This can result in reduced efficiency of the distillation process, as well as increased risk of product impurities.
Stripping is often used to concentrate a solute or remove it from a liquid stream. For example, volatile organic compounds can be removed from contaminated water by stripping with a stream of air or nitrogen. Similarly, ammonia can be stripped from wastewater using steam.
The efficiency of stripping depends on several factors, including the volatility of the solute, the surface area of contact between the liquid and gas phases, and the concentration gradient of the solute across the liquid-gas interface. The stripping process can be enhanced by increasing the surface area of contact between the two phases, increasing the concentration of the solute in the liquid phase, and reducing the thickness of the liquid-gas interface.
Difference between Absorption and Stripping
The key difference between absorption and stripping is the direction of the solute transfer. In absorption, the solute is transferred from the gas phase to the liquid phase, whereas in stripping, the solute is transferred from the liquid phase to the gas phase. Another important difference is the nature of the phases involved. In absorption, the solute is dissolved in the solvent, which is typically a liquid, whereas in stripping, the solute is absorbed by the gas, which is typically a vapor. The selection of the solvent or gas is critical to the efficiency of the process.
Another important difference is the purpose for which the two processes are used. Absorption is primarily used to remove pollutants or unwanted components from gas streams, whereas stripping is used to concentrate or remove solutes from liquid streams. Absorption is also used for the recovery of valuable solutes, such as in the separation of carbon dioxide from natural gas. Stripping is used for the removal of unwanted solutes, such as in the treatment of wastewater or the purification of chemicals.
i hope you get idea about “what is striping in distillation column? “.
The conditions under which the two processes are carried out also differ. Absorption typically requires a large contact area between the gas and liquid phases to facilitate the transfer of the solute, while stripping typically requires a large surface area between the liquid and gas phases. Additionally, the selection of the solvent or gas used for absorption or stripping may depend on the specific properties of the solute being transferred, such as its volatility or solubility.
In terms of equipment, the two processes also differ. Absorption typically uses a packed column or a tray column, which provides a large surface area for contact between the gas and liquid phases. Stripping typically uses a tower with a series of trays or packing material, which provides a large surface area for contact between the liquid and gas phases.
what is absorption ?.
Conclusion
Absorption and stripping are two important processes in chemical engineering that are used to separate different components of a mixture. While both processes involve the transfer of a solute between two phases, they differ in their mechanism, the nature of the phases involved, the conditions under which they are applied, and the equipment used. Absorption is primarily used to remove pollutants or unwanted components from gas streams, while stripping is used to concentrate or remove solutes from liquid streams. The selection of the solvent or gas used for absorption or stripping may depend on the specific properties of the solute being transferred. The efficiency of both processes can be enhanced by increasing the surface area of contact between the two phases and reducing the thickness of the gas-liquid or liquid-gas interface.
This two process are used used in fractional distillation to get purification.
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fractional distillation questions and answers
Difference between striping and absorption