What is the purpose of ion exchange in water treatment?

The purpose of ion exchange in water treatment is primarily to replace undesirable ions with more desirable ones, making it essential for enhancing water quality. This process utilizes a resin that has charged sites, where specific ions in the water are exchanged for ions attached to the resin. For instance, if hard water containing calcium and magnesium ions needs treatment, these ions can be exchanged for sodium ions, resulting in softer water.

In the context of water treatment, ion exchange is particularly valuable in softening hard water, removing heavy metals, and eliminating unwanted contaminants. This makes the water more suitable for various uses, such as drinking or industrial processes. By selectively swapping ions, this method effectively alters the ionic composition of the water, thus improving taste, reducing scaling in pipes, and preventing equipment deterioration.

The other options refer to processes that do not align with the primary goal and function of ion exchange, making them less relevant in this context. For example, increasing water temperature, adding nutrients, or removing dissolved oxygen are not outcomes of the ion exchange process.