Title : Agricultural wastes as environmentally friendly materials to remove pollutants from water
The high rate of resource consumption and large amounts of produced wastes have been reported to drive towards an ecological collapse. Interestingly, a circular economy approach could reduce this environmental concern avoiding the waste management, and all outputs (products, by-products, wastes) would become inputs (material and energy) to other processes. When the model is based on the production of renewable biological resources, and these resources are converted into value-added products, the concept of bio-circular economy take place. It means to develop an economy plan based on the production from biological resources with a sustainable transformation of wastes, offering alternatives to their dumping, burning, composting etc. About this purpose, the use of fruit Peels as food/agricultural wastes have attained interest, as adsorbent materials for water purification, avoiding their disposal according to the principles of Green Chemistry and Sustainable Development. For this purpose, this work proposes, among wastes, the use of Kiwi Peels to remove emerging pollutants (not regulated substances that could affect both human health, and the whole environment, causing severe problems) and textile dyes from water. Indeed, among the explored wastes, Kiwi Peels removed the largest number of contaminants. Kiwi Peels were characterized by adopting in synergy FTIR-ATR, TG and SEM analyses, before and after their use, and as result they are proposed as recyclable adsorbent. To infer information about the behaviour of Kiwi Peels during water treatments, model contaminants were selected and investigated; so, the role of several parameters affecting the process was assessed. The thermodynamic, the adsorption isotherms and kinetics were also studied. Finally, to extend the lifetime of Kiwi Peels, desorption experiments were carried out by using hot water or salt solutions. 10 cycles of adsorption/desorption were studied, evidencing the recycling of both pollutants and Kiwi Peels. Moreover, to find the best conditions of work for inducing the solid-state pollutant photodegradation, a preliminary investigation was performed, proposing a possible alternative for pollutant recycling and adsorbent regeneration. Finally, mixtures of pollutants were also studied and in the case of dyes, dyeing experiments were also performed, evidencing the dye ability to colour cotton fibers after the colour recycling.
What will audience learn from your presentation?
- The explained concept could be useful for the development of adsorption processes that agree with the green chemistry and bio-circular economy principles.
- Interesting information related to the study of adsorption processes will be presented and discussed, offering an overview about the use of wastes as adsorbents with their related main features.
- Innovative and green technologies to recycling the adsorbent materials will be presented.