Active carbon

Product name : Active carbon

Appearance : Powdered or granular porous amorphous carbon

Characteristics : Well-developed microporous structure, large specific surface area and adsorption activity

Application : sewage treatment, electrode, flue gas control, etc.

Preparation method : chemical activation, physical activation, etc.

Regeneration method : thermal regeneration method, electrochemical regeneration method, etc.

Application areas

(1) Treatment of oily sewage

The adsorption method for oil-water separation uses lipophilic materials to adsorb dissolved oil and other dissolved organic matter in wastewater. The most commonly used oil-absorbing material is Active carbon, which can absorb dispersed oil, emulsified oil and dissolved oil in wastewater. Due to the limited adsorption capacity of active carbon for oil (generally 30~80mg/g), high cost and difficulty in regeneration, it is usually only used as the last stage of multi-stage treatment of oily wastewater, and the oil mass concentration of the effluent can be reduced to 0.1~ 0.2mg/L.

Since Active carbon has high requirements for water pretreatment and Active carbon is expensive, in wastewater treatment, Active carbon is mainly used to remove trace pollutants in wastewater to achieve deep purification. The oily wastewater from the refinery is first treated by oil separation, air flotation and biological treatment, and then deeply treated by sand filtration and Active carbon filtration. The phenol content of wastewater dropped from 0.1mg/L (after biological treatment) to 0.005mg/L, the cyanide content dropped from 0.19mg/L to 0.048mg/L, and the COD dropped from 85mg/L to 18mg/L.

(2) Treatment of dye wastewater

The composition of dye wastewater is complex, the water quality changes greatly, the color is deep, the concentration is high, and it is difficult to treat. Treatment methods mainly include oxidation, adsorption, membrane separation, flocculation, biodegradation, etc. Each of these methods has advantages and disadvantages, among which Active carbon can effectively remove the color and COD of wastewater. Active carbon treatment of dye wastewater has been studied at home and abroad, but most of them are coupled with other processes. Active carbon adsorption is mostly used for advanced treatment or using Active carbon as a carrier and catalyst. There are many studies on using Active carbon alone to treat higher concentration dye wastewater. few.

Active carbon has a good decolorization effect on dye wastewater. The decolorization rate of dye wastewater increases with the increase of temperature, while the pH value does not have much influence on the decolorization effect of dye wastewater. Under the optimal adsorption process conditions, the decolorization rates of acidic fuchsin and alkaline fuchsin wastewater are both >97%, the color dilution ratio of the effluent is ≤50 times, and the COD is <50mg/L, reaching the national first-level emission standards.

(3) Treatment of mercury-containing wastewater

Among heavy metal pollutants, mercury is the most toxic. When mercury enters the human body, it will destroy the functions of enzymes and other proteins and affect their resynthesis. Active carbon has the ability to adsorb mercury and mercury-containing compounds, but its adsorption capacity is limited and is only suitable for treating wastewater with low mercury content. If the concentration of mercury is high, it can be treated with chemical precipitation first. After treatment, the mercury content will be about 1mg/L, and can reach 2~3mg/L at high levels, and then further treated with Active carbon.

(4) Treatment of chromium-containing wastewater

There are a large number of oxygen-containing groups on the surface of Active carbon such as hydroxyl (-OH), carboxyl (-COOH), etc. They all have electrostatic adsorption functions and produce chemical adsorption of hexavalent chromium, which can effectively adsorb hexavalent chromium in wastewater. , the adsorbed wastewater can meet national discharge standards.

The use of Active carbon to treat chromium-containing wastewater is the result of the comprehensive effects of Active carbon on the hexavalent chromium in the solution, such as physical adsorption, chemical adsorption, and chemical reduction. Active carbon treats chromium-containing wastewater with stable adsorption performance, high treatment efficiency, low operating costs, and certain social and economic benefits. Therefore, active carbon has been widely used to treat chromium-containing wastewater.