Fruit shell activated carbon plays an increasingly important role in water treatment: due to its high requirements for water pretreatment and expensive price, activated carbon is mainly used in wastewater treatment to remove trace pollutants in order to achieve deep purification.

1. Activated carbon treatment of chromium containing wastewater. Chromium is a widely used metal raw material in electroplating, and hexavalent chromium exists in different forms in wastewater with different pH values. Activated carbon has a highly developed microporous structure and a high specific surface area, with extremely strong physical adsorption capacity, which can effectively adsorb Cr (VI) in wastewater The surface of activated carbon contains a large number of oxygen-containing functional groups such as hydroxyl (- OH), carboxyl (- COOH), etc., all of which have electrostatic adsorption functions and chemically adsorb Cr (VI). It can be completely used to treat Cr (VI) in electroplating wastewater, and the adsorbed wastewater can meet the national discharge standards. The experiment showed that when the mass concentration of Cr (VI) in the solution was 50mg/L, pH=3, and the adsorption time was 1.5 hours, the adsorption performance of activated carbon and the removal rate of Cr (VI) reached the best effect. Therefore, the process of using activated carbon to treat chromium containing wastewater is the result of the comprehensive effects of physical adsorption, chemical adsorption, and chemical reduction of Cr (VI) in the solution by activated carbon. Activated carbon treatment of chromium containing wastewater has stable adsorption performance, high treatment efficiency, low operating costs, and certain social and economic benefits. Various methods of using activated carbon to separate harmful substances from electroplating wastewater.

2. Activated carbon treatment of cyanide containing wastewater. In industrial production, industries such as wet extraction of gold and silver, production of chemical fibers, coking, synthetic ammonia, electroplating, and gas production all use cyanide or by-product cyanide. Therefore, a certain amount of cyanide containing wastewater must be discharged during the production process. Activated carbon has a long history of being used for purifying wastewater, and there are increasing literature reports on its application in treating cyanide containing wastewater However, due to the small adsorption capacity of CN_ and HCN on activated carbon, which generally ranges from 3mgCN/gAC to 8mgCN/gAC depending on the variety, it is not cost-effective in terms of treatment cost.

3. Activated carbon treatment of mercury containing wastewater. Activated carbon has the ability to 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, chemical precipitation can be used first to treat it. After treatment, the mercury content is about 1mg/L, and can reach 2-3mg/L. Then, activated carbon can be used for further treatment. Activated carbon is a hydrophobic adsorbent with strong adsorption effect on organic matter in aqueous solutions.