The major impurities in crude glycerol are esters, fatty acids, and mineral ions. Activated carbon can purify it to a colorless, odorless standard.
What is glycerin?
Glycerin is a colorless, odorless, sweet and clear thick liquid, chemically named “glycerol”. Glycerin is usually made from oils and fats. It is a sweetener and humectant commonly used in the food processing industry.
Glycerin Classification
Glycerin is divided into natural glycerin and artificial glycerin.
Natural glycerin is produced by some palm plants, such as palm oil. Artificial dry glycerin is generally obtained from our well-known soaps, perfumed soaps and medicated soaps. Specifically, it is the mutual saponification of oil and alkali to generate soap and glycerin in batches. After refining, saponification, salting out, washing, alkali precipitation and other processes, glycerol is recovered and made into soap base. Petrochemical glycerin is similar to artificial glycerin. For example, the key-by-product of biodiesel production is also glycerin.
How does activated carbon work?
For glycerol decolorization, the most mainstream method currently used is to use fixed bed decolorization. As the name implies, the operation of fixed bed decolorization is actually to fill a large amount of activated carbon in the decolorization tank, and then let glycerin slowly pass through this “activated carbon decolorization tank” at a certain temperature and a certain flow rate.
When glycerin flows through the activated carbon, the pores on the surface of the activated carbon will adsorb the pigments in the glycerol that are equivalent to the pore size of the activated carbon, so as to achieve the purpose of decolorizing the glycerol by using the activated carbon.
How to choose activated carbon?
Activated carbon is used in granular and powdered forms for crude glycerine purification to reduce bulk color and fatty acids.
- Granular activated carbon
Granular decolorizing carbon is designed for efficient use in fixed or moving beds for the purification and decolorization of many aqueous and organic liquids. The particle size of 12*40mesh has been selected to give a high rate of adsorption and low resistance to flow with liquids of low to medium viscosity.
Zhulin provides high surface area, large pore volume, high density and a pore structure optimal for the absorption of color bodies and odor molecules from solutions.
Powdered activated carbon products are manufactured from vegetable raw materials by steam or chemical activation. It has excellent adsorptive capacity, high purity and good filterability.
Compared with granular activated carbon, it has a better decolorization ability. Most of our clients will choose wood activated carbon powder with the adjusted PH value.
Any questions about glycerol decolorization, contact us for better consult and advice.