Which of the following is true about granulated activated carbon filters (GAC)?

Granulated activated carbon filters (GAC) are primarily known for their ability to adsorb a variety of contaminants, making them especially effective in the removal of odors and taste from water. The main principle behind GAC filters is adsorption, where contaminants cling to the surface of the carbon granules. This process is highly effective for organic compounds and can significantly improve water quality by removing unpleasant tastes and odors.

In terms of chemical reactions, while GAC can enhance certain chemical processes, its primary function is not based on chemical reactions but rather on the physical adsorption of contaminants. Therefore, saying that GAC works primarily by chemical reactions does not accurately describe the primary mechanism at work.

Regarding total chlorine removal, GAC does have some capacity to remove chlorine, but it is not the primary method for total chlorine removal in water treatment systems. In many cases, other technologies like chemical dechlorination or specific filtration methods are utilized for more effective chlorine removal.

Overall, the strength of GAC lies in its ability to address odors and taste issues in water, rather than being the primary solution for total chlorine removal.