Polluted soils are a problem of major concern impacting the health of the global environment and human beings. Without any safe technology for polluted soil treatment, most of the contaminated soils go to landfill especially when metals are the pollutants. This research compares the performance of non ionic (Brij 35 and Tween 80) and amphoteric (cocamydopropyl hydroxysultaine (CAS) and coamydopropylbetaine (BW)) surfactants for polycyclic aromatic hydrocarbons (PAHs) and metals (mainly Pb) removal from three contaminated soils. Best removal yields have been obtained using 0.5% (w/w) of CAS surfactant with 46± 2% for PAHs and 21±5% for Pb simultaneously removed. Sodium chloride and EDTA have been shown to considerably enhance Pb solubilization (respectively 55±5% and 35±12% for [NaCl]=5.5 M and [EDTA]=0.025 M). Flotation technology has been tested as a separating technique of PAHs micelles and Pb from aqueous solution and has given good results for both contaminants (54±7% for both PAH and Pb, using [CAS]=0.5%, [NaCl]=5.5 M, pH=3). Finally, this study proposes a soil washing process using flotation to treat soil polluted with both organic and inorganic compounds. The suggested process concentrates the organic compounds in the froth and the inorganic pollutants in the liquid fraction.

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As a potential replacement for petroleum-based plastics, biodegradable bio-based polymers such as poly(lactic acid) (PLA) have received much attention in recent years. PLA is a biodegradable polymer with major applications in packaging and medicine. Unfortunately, PLA is less flexible and has less impact resistance than petroleum-based plastics. To improve the mechanical properties of PLA, PLA-based blends are very often used, but the outcome does not meet expectations because of the non-compatibility of the polymer blends. From a chemical point of view, the use of graft copolymers as a compatibilizer with a PLA backbone bearing side chains is an interesting option for improving the compatibility of these blends, which remains challenging. This review article reports on the various graft copolymers based on a PLA backbone and their syntheses following two chemical strategies: the synthesis and polymerization of modified lactide or direct chemical post-polymerization modification of PLA. The main applications of these PLA graft copolymers in the environmental and biomedical fields are presented.

Synthetic biopolymers are attractive alternatives to biobased polymers, especially because they rarely induce an immune response in a living organism. Poly ε-caprolactone (PCL) is a well-known synthetic aliphatic polyester universally used for many applications, including biomedical and environmental ones. Unlike poly lactic acid (PLA), PCL has no chiral atoms, and it is impossible to play with the stereochemistry to modify its properties. To expand the range of applications for PCL, researchers have investigated the possibility of grafting polymer chains onto the PCL backbone. As the PCL backbone is not functionalized, it must be first functionalized in order to be able to graft reactive groups onto the PCL chain. These reactive groups will then allow the grafting of new reagents and especially new polymer chains. Grafting of polymer chains is mainly carried out by “grafting from” or “grafting onto” methods. In this review we describe the main structures of the graft copolymers produced, their different synthesis methods, and their main characteristics and applications, mainly in the biomedical field.