Selective removal of hazardous metal ions in wastewater via ion-exchange and electrosorption

Abstract

Despite the increasing demand for clean water as an explosively growing population and demand for the quality of life, the amount of industrial wastewater generation is also steadily increasing. In this dissertation, the development of selective adsorption materials is demonstrated for effective purification of radioactive wastewater or heavy metal contaminated water. With the aim of selective removal of cesium, strontium, and cadmium ions, the selection and modification of materials suitable for each ionic property and process were discussed. In chapter 2, the sorption affinity of montmorillonite for cesium and strontium was improved by facile alkali-activation to prepare a porous ion-exchange material. In chapter 3, the development of a composite adsorbent is demonstrated that enables adsorption filtration with high selectivity to cesium by immobilizing potassium copper hexacyanoferrate (KCuHCF) on the electrospun nanofibers. In chapters 4 and 5, electrochemical adsorption and desorption using a copper-based metal-organic framework, focusing on the selective removal of cadmium ions and effective regeneration of spent adsorbents.