What is the role of activated carbon in purifying water?

Activated carbon is a common filter media in water treatment.

It is used in household water purification and industrial water treatment, its color is very similar to coal, and it is also black, its application in water treatment can be traced back to the 1930s the earliest, almost a hundred years ago now, about its role in water, please see the following information

Activated carbon Production process

Activated carbon is a kind of specially treated carbon, in which organic raw materials (fruit shells, coal, wood, etc.) are heated under the condition of air isolation to reduce non-carbon components (this process is called carbonization), and then react with gas, the surface is eroded to produce a microporous structure (this process is called activation).

Since the activation process is a microscopic process, i.e., the surface erosion of a large number of molecular carbons is a punctiform erosion, resulting in an activated carbon surface with numerous tiny pores.

Most of the micro-pores on the surface of activated carbon are between 2 and 50 nm in diameter. Even a small amount of activated carbon has a huge surface area of 500~1500 m2 per gram of activated carbon, and almost all applications of activated carbon are based on this feature of activated carbon.

Activated carbon classification

Coal-activated carbon coal granular activated carbon has high strength, well-developed pores, large specific surface area, especially large microporous volume, and unique advantages. Coal-activated carbon has a strong adsorption capacity for organic matter in various water, free chlorine, and harmful gases in the air is an excellent adsorbent for deep purification of urban drinking water and are used to remove bacteria and poisonous gases in the air.

Fruit shell-activated carbon

The activated carbon is refined by the process of carbonization, activation, and superheated steam catalysis, with the appearance of black indeterminate particles, and processed by a series of production processes. It has the advantages of good abrasion resistance, well-developed voids, high adsorption performance, high strength, easy regeneration, economic and durability, etc.

Wooden Activated Carbon

Wooden activated carbon is produced from high-quality fuel wood, wood chips, wood blocks, coconut shells, fruit shells, etc. It is processed and produced according to the national standard for wood-activated carbon (GB/T13803.2-1999) using today’s more popular processes: such as the physical method, phosphoric acid method, and zinc chloride method.

It has a more developed mesoporous structure and specific surface area, which makes its adsorption capacity high and filtration speed fast. High strength and low ash content, reasonable pore size distribution; high ignition point.

Purification of water

1^st: Can adsorb a small number of insoluble impurities left in water

Insoluble impurities are substances insoluble in water, meaning that the solubility of the substance is less than 1 gram at 20°C, such as sand, soil, twigs, etc.

2^nd: Absorption of most soluble impurities

Soluble impurities are substances that are soluble in water, meaning that at 20°C, the solubility of the substance is greater than 1 gram, such as color or odor in water, etc.

3^rd: Absorption of odors in water

The odor substances in water are divided into two categories: inorganic odor substances and organic odor substances. Inorganic substances such as NO2, NH3, SO2, H2S, and a few other gases have a strong odor, while most of the volatile organic substances have an odor, organic odor substances are mainly aliphatic hydrocarbons oxygenated derivatives, sulfur compounds, nitrogen compounds, and aromatic compounds

4^th: Absorbing color from water to make it transparent and clear

Free iron in the water will show yellow, excess lead will show black, and copper will show green. And so on, most of the unclean water is containing some excessive trace elements and impurities

5^th: Absorption of residual chlorine in the water

Residual chlorine refers to the chlorine in the water, in addition to the water with bacteria, microorganisms, organic matter, and inorganic matter, such as the role of the consumption of part of the chlorine amount, but also a part of the chlorine amount left

As a functional carbon material with strong adsorption capacity, it is widely used in the fields of food and beverage, medicine, water treatment, the chemical industry, etc. Among them, water treatment and food and beverage are the two main applications of activated carbon.