Comparison of the PFAS Adsorption Capabilities of a Coconut Shell Based Granular Activated Carbon and a Bituminous Coal Based Granular Activated Carbon

This research compares the ability of two granular activated carbons (GAC) from different material sources to adsorb perfluoroalkyl substances (PFAS) in deionized water. A bottle study design was used to conduct the research, which measured the reduction in perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). The carbons used were the bituminous coal based Calgon Filtrasorb 600 (F600) and the coconut shell based Evoqua AquaCarb 1230CX (AC1230CX). Additionally, the research focused on the rates at which the two contaminants were removed and compared them to previous research conducted with different forms of GAC. Results showed that both GACs were capable of reducing the concentration >95% for both PFOS and PFOA, and that the more sustainable and cheaper Evoqua AC1230CX was able to compete with a bituminous coal based carbon. Additionally, PFOS was removed more quickly than PFOA, showing a preference to perfluoroalkane sulfonic acids (PFSA) over perfluorocarboxylic acids (PFCA) similar to that which has been observed in previous research.