Learn More About Active Carbon

What is coconut shell based activated carbon?

Coconut shell based activated carbon is one major type of activated carbons which exhibits a high degree of micropores, which makes it especially suitable for water filtration applications. Coconut shell activated carbon is sourced from coconut trees which can live in excess of 70 years, therefore it can be considered a renewable resource. This type of carbon has high hardness and filtration performance characteristics which makes it a perfect choice for most treatment applications.



Production process

 Production includes a superheating process called pyrolysis where shells are transformed into char followed by a fluidization processes in a F

BR (fluidized bed reactor) where the carbon is steam activated. The FBR consists of a rotary kiln, 20 meters long and 2.4 m in diameter in which carbon is activated at temperatures in excess of 1000 degrees Celsius (1800 F).


Various types, sizes and performance characteristics can be targeted by carefully selected raw material, activation temperature, activation time and by varying the concentration of the oxidation gases. Following steam activation, the carbon can be sorted into different granular sizes using different mesh sizes.


WIT-STONE offers any coconut carbon for any application

WIT-STONE offers the word’s widest and most competitive selection of coconut shell activated carbon 

and delivers world-wide. We can manufacture specialized and tailor-made activated carbon, our standard types and sizes are guaranteed to handle the most difficult treatment tasks.



Coconut activated carbon performance

The adsorption rate of coconut shell activated carbon to organic solvent will generally decline when it contains water or the flowing gas is wet. However, by using coconut shell activated carbon which can maintain a considerable 

adsorption capacity in the wet state, it can still be used for recovery under the conditions that are not suitable for recovery, especially in the case of solvent recovery which may be heated due to oxidation and decomposition. By humidifying the adsorption gas, the temperature rise of coconut shell activated carbon layer can be suppressed, which becomes an important condition for selecting coconut shell activated carbon.

Filtration capacity and performance depends on multiple factors and carbon characteristics. Specifically, coconut shell activated carbon is known for its high levels of hardness, purity and low ash content.


Wastewater treatment of activated carbon


Due to the high requirements for water pretreatment and the high price of activated carbon, activated carbon is mainly used to remove trace pollutants in wastewater in order to achieve the purpose of deep purification.


1. Activated carbon is used to treat wastewater containing chromium.

The process of using activated carbon to treat chromium-containing wastewater is the result of the physical adsorption, chemical adsorption and chemical reduction of activated carbon on Cr (Ⅵ) in solution. Activated carbon treatment of chromium-containing wastewater has stable adsorption performance, high treatment efficiency, low operating costs, and certain social and economic benefits.


2. Activated carbon is used to treat cyanide wastewater.

In industrial production, cyanide or byproduct cyanide is used in the wet extraction of gold and silver, the production of chemical fibers, coking, synthetic ammonia, electroplating, gas production and other industries, so a certain amount of cyanide-containing wastewater must be discharged in the production process. Activated carbon has been used to purify wastewater for a long time


3. Activated carbon is used to treat mercury-containing wastewater.

Activated carbon can adsorb mercury and mercury-containing compounds, but its adsorption capacity is limited, and it is only suitable for treating wastewater with low mercury content. If the concentration of mercury is high, it can be treated by chemical precipitation method. After treatment, the mercury content is about 1mg/L, and can reach 2-3mg/L at high temperature. Then, it can be further treated with activated carbon.


4. Activated carbon is used to treat phenolic wastewater.

Phenolic wastewater is widely sourced from petrochemical plants, resin plants, coking plants and oil refining plants. The experiment shows that the adsorption performance of activated carbon for phenol is good, and the increase of temperature is not conducive to adsorption, which reduces the adsorption capacity; However, the time to reach adsorption equilibrium at elevated temperature is shortened. The amount of activated carbon and the adsorption time have the best value, and the removal rate changes little under acidic and neutral conditions; Under strong alkaline conditions, the phenol removal rate drops sharply, and the stronger the alkaline, the worse the adsorption effect.

5. Activated carbon is used to treat wastewater containing methanol.

Activated carbon can adsorb methanol, but its adsorption capacity is not strong, and it is only suitable for treating wastewater with low methanol content. The engineering operation results show that the COD of the mixed liquor can be reduced from 40mg/L to below 12mg/L, and the removal rate of methanol can reach 93.16%~100%, and the effluent quality can meet the water quality requirements of the feed water of the boiler desalted water system

Tips to distinguish quality of active carbon

Activated carbon adsorption method is the most widely used, mature, safe, effective and reliable method to remove indoor pollution in the 21st century. Although there are many kinds of activated carbon in terms of appearance and use, activated carbon has a common characteristic, that is, "adsorption". The higher the adsorption value, the better the quality of activated carbon. How to simply identify the adsorption value of activated carbon?

 1.Look at the density: if you weigh it with your hands, the more pores of activated carbon, the higher the adsorption performance, the smaller the density, and the lighter the handle.

 2.Look at bubbles: put a small amount of activated carbon into the water, produce a series of extremely small bubbles, pull out a small bubble line, and at the same time make a faint bubble sound. The more intense this phenomenon occurs, the longer the duration, the better the adsorption of activated carbon.


Advantages of coal-based activated carbon

1) The main characteristics of coal-based granular activated carbon application are low equipment investment, low price, fast adsorption speed and strong adaptability to short-term and sudden water pollution.

2) The addition of coal-based granular activated carbon has obvious effect on color removal. It is reported that the removal of chroma can reach 70%. The low chroma indicates that the removal efficiency of organic matter is high, and the removal effect of iron and manganese is good.

3) Adding coal-based granular activated carbon has obvious effect on odor removal.

4) Adding coal-based granular activated carbon is helpful to remove anionic detergent.

5) The addition of coal-based granular activated carbon is conducive to the removal of algae. The addition of coal-based granular activated carbon blocks the light absorption of algae, and has an obvious coagulation effect in the water source with low turbidity, which is helpful to remove algae in the coagulation sedimentation.

6) The addition of coal-based granular activated carbon significantly reduced the chemical oxygen consumption and the five-day biochemical oxygen demand. The decline of these indicators, which are positively related to the degree of organic pollution in water, indicates the removal of toxic and harmful substances in water.

7) Adding coal-based granular activated carbon has a good effect on the removal of phenols.

8) The addition of coal-based granular activated carbon powder greatly reduces the turbidity of effluent and greatly improves the quality of tap water.

9) The effect of adding coal-based granular activated carbon on water mutagenicity can effectively remove organic pollutants. It is a simple way to improve the quality of drinking water by conventional process.



Main factors affecting activated carbon adsorption

1.The larger the nature and surface area of activated carbon adsorbent, the stronger the adsorption capacity; Activated carbon is a non-polar molecule, 

2. The nature of adsorbate depends on its solubility, surface free energy, polarity, size and unsaturation of adsorbate molecules, concentration of adsorbate, etcwhich is easy to adsorb non-polar or very low polar adsorbate; The size of activated carbon adsorbent particles, the structure and distribution of fine pores and the surface chemical properties also have a great impact on the adsorption.

3.The PH value of wastewater and activated carbon generally have higher adsorption rate in acidic solution than in alkaline solution. PH value will affect the state and solubility of adsorbate in water, thus affecting the adsorption effect.

4. When coexisting substances and multiple adsorbates exist, the adsorption capacity of activated carbon to a certain adsorbate is worse than that of only containing this adsorbate

5.Temperature and temperature have little influence on the adsorption of activated carbon

6.Contact time: ensure that there is a certain contact time between activated carbon and adsorbate to make adsorption close to equilibrium and make full use of adsorption capacity.

Post time: Mar-21-2023