Shahnaz Ghasemi

Title : An overview of heterogonous photocatalysts and their application in wastewater treatment: Reactor design and operational conditions

Abstract:

Over the last few years, rapid urbanization and poor regulation have resulted in continuous degradation of the natural ecosystem due to unrestrained wastewater flow from numerous industries, hospital wastes, and labs. However, traditional treatment methods, primarily biological wastewater treatment, cannot eliminate resistant compounds in most cases, depending on the wastewater source. As a result, these compounds, denoted non-biodegradable compounds, remain unchanged in treated water and were more concentrated in food chains following irrigation with such water. Whether these materials will affect humans or aquatic organisms over the long term is unknown. [1].
Nevertheless, trace concentrations of such materials can result in the development of resistant bacteria or genes. Advanced oxidation processes have been considered as effective alternative methods that can be implemented as post-treatment methods. These methods are based on the generation of hydroxyl radicals which act as powerful oxidation agents and can oxide all chemical compounds. The utilization of sunlight as a sustainable source for the generation of hydroxyl radicals as oxidation agents has recently attracted great interest. one of the efficient strategies for utilizing sunlight in water treatment relies on photocatalytic techniques [2]. Photocatalysis, especially heterogeneous photocatalysis technology, is one of the most promising approaches to using sunlight energy to overcome environmental contamination issues. In this regard, green synthesis and application of semiconductor-based nanocomposites for treating residual contamination in wastewater are considered as practical solutions for eliminating such contaminations. In this research, Ionic liquids (ILs) as low vapor pressure and green solvents have been applied to synthesize different photocatalysts such as TiO₂ [3], BiVO₄, and FeVO₄. The effect of IL on crystal structure, surface area, bandgap, and photocatalytic activity of mentioned photocatalysts has been investigated. Moreover, the impact of treatment conditions and operational parameters on the photocatalytic degradation of pollutants has been extensively studied.
Audience take away:

•    Challenges associated with water reuse
•    Weaknesses of traditional wastewater treatment techniques
•    Reuse of treated water and concerns about water quality
•    Technology for posttreatment of different wastewater
•    Green solvent-based synthesis of photocatalysts

Biography:

Dr. Shahnaz Ghasemi received her MSc and Ph.D. degrees in physical chemistry from Sharif University of Technology, Tehran, Iran. Her studies focused on both environmental and energy issues. She also complished her post-doctorate in Material Sciences with special attention on synthesis and properties of materials for Lithium-ion Batteries within TUM CREATE –a joint research program between TUM (Technical University of Munich), Germany, and NTU (Nanyang Technological University), Singapore. Currently, she is an assistant professor at Sharif University of technology, working on environmental and energy challenges.