Activated carbon (AC), with its highly porous structure and large specific surface area, has become an indispensable material in advanced wastewater treatment, especially for eliminating emerging contaminants (ECs) that traditional processes fail to address. Unlike conventional adsorbents, AC's hierarchical pores-from micropores to mesopores-enable it to trap a wide range of pollutants, including pharmaceuticals, personal care products, and industrial micro-pollutants, through physical adsorption and chemical interaction.
In modern wastewater treatment plants, granular activated carbon (GAC) is widely used in post-treatment stages. It operates via a fixed-bed adsorption system, where wastewater flows through a layer of GAC, and ECs are adsorbed onto the carbon surface. This process not only removes toxic substances but also improves water biodegradability, reducing the environmental risk of treated effluent discharged into rivers or reused for irrigation. Recent innovations have led to the development of modified AC, such as nitrogen-doped AC, which enhances adsorption capacity for polar ECs by introducing functional groups on its surface.
Compared to other advanced treatment technologies like ozonation or membrane filtration, AC adsorption is cost-effective, easy to operate, and environmentally friendly, as it does not produce harmful by-products. Moreover, spent AC can be regenerated through thermal or chemical methods, reducing waste generation and lowering operational costs. With the increasing concern over water scarcity and EC pollution, AC's role in ensuring water safety is becoming more prominent, making it a key material for sustainable water management in the 21st century.
Illustration Description: A high-resolution image of granular activated carbon (GAC) in a fixed-bed adsorption column, with wastewater flowing through the column. The image shows the porous structure of GAC under a scanning electron microscope (SEM) as an inset, highlighting its microporous and mesoporous features.
https://www.naturecarbon.com/wood-based-activated-carbon
