Elimination of Humic Acid from Aqueous Sample Using Zinc Oxide/Graphene Oxide-Coated Microbeads.

Natural organic matter (NOM) is known to cause major problems with drinking water quality management, such as sedimentation of disinfectants during the purification process, microbial growth of water pipes, and corrosion of pipes. For efficient and continuous removal of NOM from drinking water, a packed bed-type platform containing microbeads based on nanostructured zinc oxide (ZnO) was developed. ZnO was synthesized on graphene oxide (GO)-coated microbeads by optimizing the ZnO concentration and reaction time. The morphology of the synthesized ZnO-coated microbeads was confirmed by scanning electron microscopy, and an adsorption test was conducted using a cationic dye. The ZnO/GO microbeads were packed in a microtube. A humic acid contaminated aqueous solution was allowed to flow through the microbeads, and its removal rate was measured by UV-vis spectroscopy. This study confirmed that the purification platform containing ZnO removed more than 90% of humic acid of about 1,000 ppm.