Today I will talk with you about How to remove oil, fat, wax, and other impurities from a textile material.
There are 3 Processes to remove oil, fat, wax, and other impurities from a textile material.
1. Saponification
2. Emulsification
1. Saponification:
Vegetable oils, animal oils, and mineral oils are not soluble in water. Because oil and water do not like each other. Fabric sizing products contain oily substances which make the fabric hydrophobic. This means that even if the cloth is soaked in water, water cannot enter its fibers. The oil prevents the cloth from getting wet. Which causes serious inconvenience in the subsequent process. In this condition, it is necessary to remove the oily substance from the cloth.
When oil is heated in water by sodium hydroxide (NaOH), fatty acids i.e. stearic acid and glycerin are obtained. Glycerin soluble fatty acid reacts with sodium hydroxide to form its sodium salt, a soap that is soluble in water. This reaction is called saponification. As a result, water-soluble oils become water-soluble substances.
2. Emulsification:
The wax and mineral oil of the sizing product cannot be removed by saponification. Wax is an ester of higher fatty alcohols and fatty acids. This wax and mineral oil is removed through emulsification. Emulsifying is the process of separating the product (waste) by dispersing it in water with the help of the emulsifying agent. This process is used during cotton souring. Where removes non-sampling able oils and waxes through emulsifying agents. Soap (washing soap) with sodium hydroxide and the wetting agent is usually a good emulsifying agent.
3. Detergency:
Saponification removes wax and mineral oils through vegetable oils and emulsifiers, but also as a sizing material on a cloth to remove (China clay) and other hard wastes that contain dust and dirt. After the oil, mineral oil, and wax are removed, all these binding products become loose and it needs to be removed from the fabric with proper measures. Leaving the cloth, it is sprinkled in the scouring solution and re-deposited in another part of the cloth. Detergents are used in the scouring solution to prevent such re-accumulation. Which prevents such hard particles from accumulating on the surface of the fabric. Soap is an excellent detergent.
A good detergent is certainly a good wetting agent. If detergent is used in the Kier boiler, there is no need to use any other wetting agent. So proper detergent is an important issue during scouring.
