(57b) Separate to Sustain: Waste-Derived Solutions for Remediating Waters Polluted with Emerging Contaminants

With sustainable development goals (SDGs) and circular economy in mind, this talk delves into the ongoing efforts developed by our research group, Sustainability-Targeted Separation (STAR-SEP) group to tackle the pressing issues of water treatment and waste management. As a result of the growing advancements in food and pharmaceutical industries, and the expansion in urbanization, tons of solid waste are produced annually. For instance, about 55 million metric tons of food waste and 2.2 billion tons of construction waste are produced globally every year. On the other hand, these industrial activities along with domestic ones generate wastewater effluents polluted with conventional and emerging contaminants, also known as contaminants of emerging concern or CECs. The latter class of contaminants, the focus of this talk, has been historically overlooked in wastewater treatment plants since they have been newly introduced into the environment or not properly monitored due to lack of appropriate detection tools. CECs fall within different categories of contaminants that span almost every aspect of life from pharmaceuticals, personal-care, and life-style products to pesticides and industrial additives. Evidence from previous studies indicated hazardous effects for these contaminants on human health and the environment. To close the loop between the solid waste generation and wastewater pollution, our work integrates waste valorization processes into water treatment systems to target more specifically CECs, notoriously known for their accumulation and persistence in water environments. The talk will provide some examples to highlight this integration, demonstrating three main approaches. First, environmentally conscious processing of agri-food wastes as such, and deploying them as efficient and facile water sorbents for CECs. Second, converting agri-food and construction wastes into value-added functional products for selective water remediation, such as biochars, hydrochars, and biogenic nanoparticles. Third, incorporating the waste-derived products into nanocomposites with other bio-based or synthetic materials such as biodegradable polymers and metal organic frameworks to enhance their functionality and sorption performance. While walking through these examples, the application and implementation of concepts of process optimization, green processing, material regeneration and reuse, life cycle assessment, magnetic separation, scaling up to continuous column systems, and challenges with multi-component/complex water environmental systems will be thoroughly discussed to manifest their implications. Some of these integrated approaches marked success stories in water-food-energy nexus, yielding high removal efficiencies for CECs (>90%) in short time durations (< 1h) within complex matrices of contaminants adopting greener options for resource management and energy/material reduction and reuse.