Environmentally Friendly Tools for the Removal of Emerging Pollutants from Natural Matrices

In this work of thesis are contained four different projects on sustainable remediation techniques for the decontamination of natural matrices have been developed and valued. The original intent shared by these projects is to develop innovative solutions for emerging pollution cases. Porous synthetic silica materials, commonly used in catalysis, have been studied, valued and adapted for use in pollutant decontamination. In the first project, synthetic high silica faujasite used for antibiotics sorption from waste waters was tested for regenerability and its reuse after solvent desorption or thermal regeneration. The tested high silica Y has been regenerated with thermal treatments; the most effective (and less costing) temperature and treatment time was determined and the regenerated zeolite was successfully reused. Another successful option, solvent desorption, was also validated. In the second project, mineral oil contamination of recycled paper and paperboard – with particular attention to food-contact paperboard – was accounted. A hydrocarbon-specific sorbent material was developed, suitable to be used during industrial processes of paper recovery and recycling. The material, capable to retain up to 184% of its dry weight, was a modified mesoporous silica. Its capacity to adsorb and retain hydrocarbons from highly wet pulp were successfully tested in a pilot-scale plant, and the utilization of the said material was patented. In the third project, a mild sediment washing technique in order to remove Cu and Zn from a contaminated sediment of a land reclamation consortium canal. In the study presented the treatment efficacy to remove heavy metals is assessed, as well as an aggregate structural stability evaluation post-treatment. In conclusion, a multidisciplinary project on humic substances is introduced. Humic substances have been chemically grafted onto silica gel, in order to exploit their sorbent capacity to retain pollutants, or facilitate their degradation in water solutions.