| The presence of toxic and inhibitory components in water and soil has become an environmental issue due to their negative impacts on human health. Degradation and mineralization of textile effluents and pharmaceutical wastes has been a matter of considerable interest during past decades because of their potential toxicity and aesthetic issues. Among the several methods developed in industrial effluent treatment, Advanced Oxidation Processes (AOPs) are increasingly used as a potential alternative for the degradation and mineralization of dyes solutions. AOPs are a class of wastewater treatment method that can be employed to fully or partially oxidize organic chemicals by means of chemical, photochemical, sonochemical, or electrochemical reactions. AOPs generate hydroxyl radicals (•OH) as the primary oxidant. Hydroxyl radicals are an extremely powerful, short-lived oxidizing agent, and are non-selective in nature and could react with a wide range of organic chemicals. In AOPs, other reagents such as ozone, hydrogen peroxide, homogeneous and heterogeneous catalysts produce or enhance the production of oxidizing radicals. AOPs are able to enhance the biodegradability of contaminants through converting recalcitrant contaminants into smaller and consequently more biodegradable intermediates.;Multi-lamp photoreactors perform with higher degradation and mineralization efficiency due to their higher light intensity distribution. In the first stage, different multi-lamp photoreactor geometries were modeled using computational fluid dynamics (CFD). Then an experimental setup (multi-lamp sonophotoreactors) was designed and built in order to compare the effectiveness of different AOPs (photolysis, sonophotolysis, photoFenton, photoFenton-like, sono-photoFenton, and sono-photoFenton-like processes) and also the impact of UV lamps.;The synergetic effect in intensified AOPs is a complex function of different parameters (i.e., initial H2O2 concentration, initial catalytic concentration, etc.). photoFenton(-like) and sono-photoFenton(-like) processes performed with higher mineralization efficiency compared to photolytic and sonophotolytic processes.;A novel bench scale experimental external-loop airlift sonophotoreactor was designed and built in order to study the intensification in degradation and mineralization of organic compounds. The reactor was a combination of three different reactors comprising of a photochemical reactor, sonochemical reactor, and pneumatic reactor. Sulfadiazine and p-aminophenol from pharmaceuticals were selected as model compounds because of their high solubility in water and their non-biodegradable nature. A single compound (methylene blue solution) and multi-component dye wastewater (containing four different nonbiodegradable dyes) were also used to investigate their degradation and mineralization efficiency subjected to different AOPs. Statistical analysis and modeling methods such as response surface methodology and artificial neural networks were used in order to model the linear and interacting impacts of different parameters such as initial waste concentration, initial H2 O2 concentration, initial catalyst concentration, ultrasonic power, pH, and air flow rate. Respirometric studies were conducted to investigate the biodegradability enhancement of chemically pre-treated wastewaters. |
