The circular economy (CE) has been a European Union (EU) priority since 2014, when first official document on the CE was published. Currently, the EU is on the road to the transformation from a linear economy model to the CE model. In 2019, a new strategy was announced – the European Green Deal, the main goal of which is to mobilize the industrial sector for the CE implementation. The CE assumes that the generated waste should be treated as a secondary raw material. The paper presents an analysis of the possibility of using selected groups of waste for the production of fertilizers. Moreover, an identification of strengths and weaknesses, as well as market opportunities and threats related to the use of selected groups of waste as a valuable raw material for the production of fertilizers was conducted. The scope of the work includes characteristics of municipal waste (household waste, food waste, green waste, municipal sewage sludge, digestate), industrial waste (sewage sludge, ashes from biomass combustion, digestate) and agricultural waste (animal waste, plant waste), and a SWO T (strengths and weaknesses, opportunities and threats) analysis. The fertilizer use from waste is determined by the content of nutrients (phosphorus – P, nitrogen, potassium, magnesium, calcium ) and the presence of heavy metals unfavorable for plants (zinc, lead, mercury). Due to the possibility of contamination, including heavy metals, before introducing waste into the soil, it should be subjected to a detailed chemical analysis and treatment. The use of waste for the production of fertilizers allows for the reduction of the EU’s dependence on the import of nutrients from outside Europe, and is in line with the CE.

A new composite adsorbent was prepared by modifying low cost local adsorbent (LCL) using MgFe layered double hydroxide (LDH). This low cost local adsorbent was also prepared from the activation of date palm leaf derived from agricultural waste. In comparison to the low LCL, the adsorption capacity of the new composite adsorbent (LCL/MgFe-LDH) was improved. This was measured in terms of its ability to remove lead from wastewater. The Scanning electron microscope (SEM), Energy dispersive spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR) and the specific surface area by the (Brunauer, Emmett and Teller) theory (BET) tests were conducted for the characterisation of LCL and LCL/MgFe-LDH. The behaviour of the lead adsorption processes by using LCL/MgFe-LDH as adsorbent was investigated in batch experiments by examining different values of solution pH, contact time, adsorbent dose and initial Pb2+ concentration. High removal efficiency was exhibited by LCL/MgFe-LDH, a value almost double that of LCL. This was attributed to the increase in surface area of LCL/MgFe-LDH (79.7 m2·g–1) in contrast to the surface area of LCL (24.5 m2·g–1). The Freundlich equations and pseudo-second-order kinetics model were appropriate for the provision of adsorption equilibrium data for Pb2+ on adsorbents. These results reveal the great potential of the new composite adsorbent (LCL/MgFe-LDH) if applied to the absorption of heavy metal ions.

Day-to-day life advanced composite materials usage is increasing continuously and replacing the existing monolithic materials. These composite materials are designed and fabricated for human needs with specific applications and also meet the standard requirements. In present study, the agro and industrial wastes derived ceramic reinforcements based Aluminium metal matrix composites, i.e. AA7075/welding slag and AA7075/Rice husk ash are fabricated through liquid metal stir casting route with varying the reinforcement contents from 2 to 12 (wt.%) in the matrix. Mechanical and microstructural characterization of the AA 7075 metal matrix composite were measured and compared to the base material. The results show an improved mechanical strength and high hardness in composites. Impact energy has also significantly improved at higher concentrations of reinforcement particles. Impact energy of the composites increases to 3 J for 9% and 12%, the maximum tensile strength obtained is 173 MPa for 12% Weld Slag MMC. The highest hardness achieved is 98 BHN for 12% Weld Slag MMC. Furthermore, the microstructural results reflect significant grain refinement with stir casting process with good interface characteristics in the matrix and uniform dispersion of agro reinforcement’s particles.