Editorial: Air and Water Purification Processes through Photocatalysis—Scale-Up Perspectives, 2nd Edition

In the face of escalating environmental challenges, innovative solutions for purifying air and water are more critical than ever [...

An Overview of Environmental Catalysis Mediated by Hydrogen Peroxide

The use of hydrogen peroxide (produced in situ or ex situ) as the main agent in oxidative processes of environmental pollutant removal is widely studied. The degradation of water pollutants, such as dyes, pharmaceuticals, cosmetics, petroleum derivatives, and even pathogens, has been successfully obtained by different techniques. This review gives an overview of the more recent methods developed to apply oxidative processes mediated by H2O2 and other reactive oxygen species (ROS) in environmental catalysis, with particular attention to the strategies (Fenton-like and Bio-Fenton, photo- and electro-catalysis) and the materials employed. A wide discussion about the characteristics of the materials specifically studied for hydrogen peroxide activation, as well as about their chemical composition and morphology, was carried out. Moreover, recent interesting methods for the generation and use of hydrogen peroxide by enzymes were also presented and their efficiency and applicability compared with the Fenton and electro-Fenton methods discussed above. The use of Bio-Fenton and bi-enzymatic methods for the in situ generation of ROS seems to be attractive and scalable, although not yet applied in full-scale plants. A critical discussion about the feasibility, criticalities, and perspectives of all the methods considered completes this review

Behavior of polypyrrole-coated cotton fabric undergoing biodegradation in compost-enriched soil

This study investigated the biodegradation behavior of cotton fabrics treated with polypyrrole, a polymer with conductive and antibacterial properties. Fabric samples were buried in compost-enriched soil for 10, 30 and 90 days. The biodegradation level was initially estimated by a visual inspection of the fibers and by the determination of the fabric weight loss. Other physical–chemical changes of fibers during the biodegradation process were analyzed by microscopy, thermal analyses and infrared spectroscopy. The surface resistivity of the fabrics was also measured. The results obtained comparing the bare cotton samples and the polypyrrole-added ones suggested that, on the one hand, polypyrrole hindered/delayed the biodegradation of cotton in compost-enriched soil, probably exercising its inherent antimicrobial feature during the first period of burial. On the other hand, over time, polypyrrole seemed to represent the first compound attacked by the microorganisms, preserving the cotton substrate. Despite the absence of dedicated literature regarding polypyrrole biodegradation, the mechanism hypothesized in this paper involves the loss of conjugation, as a consequence of de-doping, oxidized functionalities up to local cycle breaking