What is Glycerol?
Glycerol is a colorless, odorless, viscous organic compound with the chemical formula C3H8O3. Glycerine is liquid at indoor temperature and has a high solubility and consistency and is commonly used as a raw material or additive in the cosmetic, pharmaceutical, food, and tobacco industries.
Glycerol Production Methods
The industrial production methods of glycerine can be divided into two main categories: the method using natural oils and fats as raw material, the resulting glycerine is commonly known as natural glycerine; the synthetic method using propylene as raw material, the resulting glycerine is commonly known as synthetic glycerine.
Oil chemical refining process: crude oil → filtration → degumming (hydration) → deacidification (alkali refining) → decolorization → deodorization → finished oil
Physical refining process for oils and fats: crude oil → filtration → degumming (acidification) → decolourisation → deacidification (water distillation) → deodorisation → finished oil
What is Glycerol Decolorization?
Glycerine decolorization is an industrial process designed to remove impurities from glycerine to make it clear. The use of granular activated carbon is one of the common methods of decolorising glycerine and the process is usually as follows:
Preparing the activated carbon: put the granular activated carbon into the decolorization equipment, usually a vertical column or cylinder container.
Pretreatment of glycerine: Pre-treatment of the glycerine to be decolored, usually by removing impurity substances, acidification, or alkalization.
Adding glycerine: Slowly add the pre-treated glycerine to the decolorization unit containing the activated carbon. This is usually done by passing the liquid into the top and distributing it evenly over the entire bed of activated carbon.
Decolorization: The glycerine enters from the top and gradually passes through the activated carbon bed, where the micro-pores on the activated carbon attract impurity substances from the glycerine, removing them from the glycerine. This process can take several hours or even days, depending on the quality of the glycerine and the specification of the decolorization equipment.
Collection of glycerine: the decolored glycerine is collected from the bottom, usually through a pipe, and subsequently processed, e.g. for re-refining or direct use.
Notice: activated carbon adsorbs impurities as well as other substances in the glycerine, so after decolorization, the glycerine needs to be re-treated to remove any residual substances in the glycerine from the activated carbon. In addition, the activated carbon will gradually become saturated and will need to be replaced or regenerated to maintain its decolorization effect.
Activated Carbon for Glycerol Decolorization
Granular activated carbon used in the decolorization of glycerine needs to meet the following requirements:
High adsorption capacity: Granular activated carbon needs to have a high adsorption capacity in order to adsorb trampolines in glycerine and make it more effective in decolorization. In general, the larger the specific surface area of the carbon material, the higher the adsorption capacity.
Good chemical stability: Granular activated carbon needs to have high chemical stability to avoid side reactions or reduced adsorption during decolorization. In particular, activated carbon needs to be resistant to acids and bases in the case of pretreatment with acids or bases.
High-temperature resistance: The temperature of glycerine decolorization is usually high, so granular activated carbon needs to have good resistance to high temperatures in order to avoid loss of adsorption capacity or melting of the carbon particles during decolorization.
Suitable carbon particle size: The size of the carbon particle affects the absorption rate and the effect of the activated carbon. The particle size of granular activated carbon needs to be adapted to the specifications of the decolorization equipment. Generally speaking, the smaller the particle size, the faster the adsorption rate, however, too small a particle size can lead to excessive pressure in the carbon bed and affect mobility.
Low ash and impurity content: The lower the ash and impurity content of granular activated carbon, the less impact it will have on the purity and color of the glycerine. For this reason, granular activated carbon needs to have a low ash and impurity content in order to ensure the decolorization effect.
In conclusion, granular activated carbon plays a vital role in the decolorization process of glycerine and its adsorption performance and quality directly affect the quality and purity of glycerine. Therefore, it is important to choose the right granular activated carbon. Huamei granular activated carbon has been proven in the market to play an excellent role in the decolorization of glycerine. Feel free to contact our sales manager for a more professional product introduction.
