A 95% confidence interval was estimated from 2-methylisoborneol (2-MIB) numbers, as an index of adsorption capacity described in this article, for 31 different powdered activated carbons (PACs) used for drinking water purification. The seven PACs selected in this study were chosen as five of them were within the 95% confidence interval and the other two PACs were not. The PACs were assessed based on previous studies, which represented the relationships between 2-MIB adsorption capacity and surface area, pore distribution, bulk oxygen content and surface oxygen functional groups. From the results, we assumed the 2-MIB adsorption mechanism and studied relationships between 2-MIB number and ash content of PAC or pH value of PAC slurry. It was shown that the 2-MIB number correlated with the ash content and the pH value. Easily measurable ash content and pH values would help a water supplier briefly screen PACs for removing 2-MIB at a water purification facility.
Defective graphene nanosheets for drinking water purification: adsorption mechanism, performance, and recovery
