Carbon is used in multimedia filters in drinking water treatment plants to remove organics, in carbon columns for treatment or advanced treatment of wastewater, and in the powder form (powdered activated carbon or PAC) in biological treatment plants to remove the organics where treatment organisms may be slow or unable to remove them. Granular activated carbon selectively removes soluble organics from water or wastewater by adsorption of these molecules to the carbon particle surfaces. Granulated carbon has an extremely large surface area per unit weight (approximately 1000 m2/gram) due to the many pores within the carbon particles and the vast areas of the walls within these pores.
This experiment will help you understand which type of carbon is most effective for removing organic pollutants. Also, it will help to explain how carbon removes organic pollutant from water.
Material Needed:
- Pulverized coal
- Activated charcoal(carbon)
- Charcoal(ground)
- Food coloring
- 16 capped containers
- Color pencils
Procedure:
- Add equal amounts of each color to three capped containers with equal amounts of carbon in each (each color mixture having one of each carbon source).
- Shake each of the containers thoroughly mixing the carbon sources and food coloring.
- Observe, record, and compare the color of each solution after settling or filtering to the color of the original food coloring solution in the containers without carbon. Use coloring pencils to indicate the results.
Source: Enviromental Protection Agency