The SMARTER project is devoted to address two pressing environmental issues related to wastewater: metals accumulation and widespread presence of organic contaminants. The goal is to develop a simple technology based on materials derived by recycled industrial waste, able to purify specific streams from primary treatment before reuse or safe disposal. In detail, SMARTER aims at proving the feasibility of a composite material, assembling adsorbent and photocatalytic constituents in a membrane or in a 3D foam-like structure, intended for the treatment of hybrid wastewater, namely containing both inorganic (IPs) and organic pollutants (OPs), in particular of some specific heavy metal ions (Fe3+, Cu2+, Mn2+, Ni2+), pesticides and drugs.
Reduced graphene oxide (rGO) will be tested as adsorbent free-standing material taking advantage of its dual nature of being effective in capturing metal ions and in forming thin membranes if properly prepared. To do that, GO needs to be reduced in a controlled way and this will be accomplished in an environmentally friendly fashion by using ascorbic acid instead of commonly used strong reducing agents, often toxic. Whereas the well-known photocatalytic properties of titanium dioxide will be exploited to degrade the organic fraction of pollutants. The appropriate amount of photocatalyst will be defined to preserve the self-assembling capability of the rGO-based membrane. Pursuing a circular economy logic, one of the SMARTER core subjects will be the replacement of titania with tionite, a secondary raw material, originating from residues of the slag dissolution process for titania itself. The recycling of a waste material, such as tionite, unconventional with respect to current technology, is an important and critical part of this project thought to reduce the overall environmental impacts, which will be analytically evaluated by means of the life cycle assessment (LCA) methodology. Until now, composites that use combinations of semiconductors, noble metals or graphene derivatives lack the required durability and utilize high-cost materials. To overcome these drawbacks, the project will focus on designing a composite, both sustainable and able to bear repeated use, along with qualities that enable low-cost recovery from effluent streams, with a potential large-scale application.
The objectives of SMARTER are in agreement with the mission 2 “Green Revolution and Ecological Transition” of National Recovery and Resilience Plan (NRRP) of the Italian Government and its outcomes would be beneficial for the society in terms of waste recycling and improvement of purification treatments of water.