This thesis investigates an innovative advanced oxidation process that has been developed to use adsorption combined with electrochemical regeneration. The process uses a graphite based adsorbent material, which enables low cost electrochemical treatment of wastewater. The work in this thesis was carried out to study the effect of electrochemical regeneration on the liquid, solid, and gaseous phases.This project investigates the fate of organic pollutants during the wastewater treatment process by analysing the gases produced, the adsorbent material and the water treated. This study evaluates the removal process under different operational parameters based on the pollutant reduction in the liquid phase and adsorbent regeneration efficiency. In addition, the relationship between adsorbent Nyex1000 and reaction products in the gaseous phase is important to indicate the source of gaseous products and lifetime of adsorbent Nyex1000.The process of adsorption and electrochemical regeneration was conducted using adsorbate acid violet 17 and phenol. Effect of electrochemical regeneration over adsorbent Nyex1000 solid phase was determined using scanning electron microscope, time-of-flight secondary ion mass spectrometry, and atomic force microscopy. This technique of solid analysis was also efficient in determining penetration level of pollutant in the solid phase. The study of solid surface chemistry was also essential to determine favored active sites supporting the adsorption process. C13 labelled phenol contaminant was used so that the distribution of carbon from adsorbent Nyex1000 to that from adsorbate.It was observed that electrochemical regeneration achieved regeneration efficiency over 100% by oxidising not only loaded contaminant but also the surface of adsorbent Nyex1000. The process of electrochemical regeneration was found dependent on both adsorbent initial concentration and charge passed. For solid phase analysis, results agreed with Lagergren 2nd order kinetics that adsorption process was achieved based on chemical bonds between adsorbate and active site at adsorbent surface. In addition, carbon balance between adsorbent phenol and gaseous product represented by carbon monoxide and carbon dioxide recorded in the range of 41-52% carbon recovered indicated other oxidation route with respect to phenol oxidation. Moreover, using C13 labelled phenol indicated that applied charge is being consumed partially in oxidising both adsorbent Nyex1000 surface and adsorbate C13 labelled phenol with a range of 70-80% charge consumption towards adsorbent Nyex1000 oxidation.
|Date of Award||1 Aug 2016|
- The University of Manchester
|Supervisor||Stuart Holmes (Supervisor)|