MOdeling the Recycling of PHOsphate: aiming for a SustaInable phosphoruS economy (MORPHOSIS)

Elements such as carbon, nitrogen, oxygen, phosphorus and sulfur circulate naturally between living organisms, the atmosphere, and the Earth's crust (biosphere, hydrosphere, geosphere, lithosphera) through processes known as biogeochemical cycles. These have created suitable conditions to sustain life on Earth by balancing a myriad of chemical, biological and geological factors such as elemental concentration/distribution, energy flow, population dynamics and tectonic activity, among others. Since industrialization, this delicate balance has been disrupted by large-scale human activities. For instance, phosphorus is unnaturally transported from rocks to rivers and oceans as agricultural runoffs (fertilizers, pesticides and detergents), causing the eutrophication of water bodies. This linear approach in the utilization of such element is both economically and environmentally unfeasible, making the adoption of a circular phosphorus economy imperative. Herein the development of functionalization strategies of phosphates, such as those found in agricultural and municipal waste, is proposed. By using chemical refining, it is expected that phosphates can be transformed into useful compounds for other purposes, for example fine chemicals. Chemical refining will comprise the use of deoxygenating or reducing agents to access reactive P(V) or P(III) synthons that can be further functionalized by thermal, electrochemical or photochemical methods. As case studies, the project will first address the recovery of phosphorus from simple model substrates such as organic or inorganic phosphates. In an advanced stage of the project, more complex substrate matrixes will be employed aiming to mimic realistic samples (agricultural and municipal waste). The ideal goal is the development of robust, practical and sustainable methodologies for the recuperation of phosphorus from agro-industrial and urban discards. Understanding the methodologies’ design principles, including their limitations, potential sustainability issues and scalability, is essential and would pave the way to achieve the ultimate goal of a circular P economy.