Catalytic wet peroxide oxidation: a route towards the application of hybrid magnetic carbon nanocomposites for the degradation of organic pollutants. A review

Several motivations have prompted the scientific community towards the application of hybrid magnetic carbon nanocomposites in catalytic wet peroxide oxidation (CWPO) processes. The most relevant literature on this topic is reviewed, with a special focus on the synergies that can arise from the combination of highly active and magnetically separable iron species with the easily tuned properties of carbon-based materials. These are mainly ascribed to increased adsorptive interactions, to good structural stability and low leaching levels of the metal species, and to increased regeneration and dispersion of the active sites, which are promoted by the presence of the carbon-based materials in the composites. The most significant features of carbon materials that may be further explored in the design of improved hybrid magnetic catalysts are also addressed, taking into consideration the experimental knowledge gathered by the authors in their studies and development of carbon-based catalysts for CWPO. The presence of stable metal impurities, basic active sites and sulphur-containing functionalities, as well as high specific surface area, adequate porous texture, adsorptive interactions and structural defects, are shown to increase the activity of carbon materials when applied in CWPO, while the presence of acidic oxygen-containing functionalities has the opposite effect.

Synthesis of glycerol-based carbon materials as environmental application

Crude glycerol, obtained from the biodiesel production, is actually an abundant and low-cost feedstock, making the preparation of carbonaceous materials by partial carbonization and sulfonation of this by-product an interesting research focus. Bearing this in mind, the aim of this study is to explore several types of glycerol-based carbon materials synthesized by partial carbonization of glycerol in concentrated sulphuric acid solution for the removal of flumequine and tetracycline from aqueous solutions. This study is focused on the synthesis and application of glycerol-based carbon materials as adsorbents for the removal of the antibiotic compounds flumequine and tetracycline from aqueous solution. The different synthesized materials were labelled as GBCM followed by a subscript number corresponding to the activation temperature in oC (i.e., GBCM200, GBCM300, and GBCM350)