Abstract: The present disclosure relates to the use of a strongly basic anion exchange resin, in the form of dimethylethanolamine (DMAE) resin, for the removal of the per- and polyfluoroalkyl substances (PFASs) from fluids such as water.

Abstract: A method of removing chromium from water using a weak base anion exchange resin at a pH above about 5 includes the step of periodically reducing a flow of the water through the ion exchange resin for a rest period, such that a secondary mechanism of chromium removal predominates, wherein chromium ions are removed from the weak base anion exchange groups and precipitated inside the ion exchange resin. In an alternative embodiment, rather than resting, the ion exchange resin is periodically conditioned with an acid so as to enhance the secondary mechanism.

Abstract: A method of preferentially removing or recovering silica from a source, including aqueous sources such as ground and potable water, which utilizes a modified ion exchange material that holds or captures the silica by ion exchange with a metal contained in the exchange material whereby the method includes the steps of: providing an ion exchange material; immobilizing a metal complex to form at least a portion of a metal containing substance inside the ionic exchange material; and contacting the source with at least a portion of the metal containing ionic exchange material.