192 documents found, page 1 of 20
Selective biphasic oxidation of nitrogenated contaminants with H2O2 using polyo...
Roman, Fernanda; Piccinin, Larissa; Silva, Adriano S.; Díaz de Tuesta, Jose Luis; Vieira, Admilson L.; Silva, Adrián; Faria, Joaquim; Gomes, HelderLiquid/liquid biphasic oxidations are extensively employed in the chemical industry to manufacture a variety of chemicals and for environmental issues, such as the oxidative denitrogenated (ODN) and desulfurization of fuels. The ubiquitous presence of nitrogenated and sulfonated compounds in petroleum-derived fuels is associated with environmental and health issues, driving legislation to become stricter regard...
Plastic waste-derived carbon nanotubes: Influence of growth catalyst and cataly...
Roman, Fernanda; Silva, Adriano S.; Díaz de Tuesta, Jose Luis; Baldo, Arthur Pietrobon; Lopes, Jéssica Paula Marim; Gonçalves, Giane; Pereira, Ana I.Low-density polyethylene (LDPE) was used in this work to grow carbon nanotubes (CNTs) by chemical vapor deposition (CVD) over catalysts based on Ni, Fe and Al, synthesized either by co-precipitation (C) or wet impregnation (I) methods, with CNT yields in the range of 16–33 %. The morphology of the CNTs was directly influenced by the route used for the CVD catalyst synthesis, with co-precipitation-derived CVD ca...
Selective denitrification of simulated oily wastewater by oxidation using Janus...
Roman, Fernanda; Díaz de Tuesta, Jose Luis; Sanches, Flávia Kim; Silva, Adriano S.; Marin, Pricila; Machado, Bruno F.; Serp, Philippe; Pedrosa, MartaThe intense industrial development has resulted in several consequences for human and environmental health, including the increased discharge of oily products in water bodies. Oily products are widely used in industry, often bearing an associated high cost. Finding alternatives to treat oily wastewater aiming at recovering oily and water phases is an approach allowing recovery of products of economic interest. ...
Carbon nanomaterials from polyolefin waste: effective catalysts for quinoline d...
Roman, Fernanda; Piccinin, Larissa; Silva, Adriano S.; Díaz de Tuesta, Jose Luis; Freitas, Isabella V. K.; Vieira, Admilson L.; Lenzi, Giane G.Quinoline (QN) is highly toxic and carcinogenic and has been detected in soil, groundwater, and biological tissues. Advanced oxidation processes (AOPs) have shown promise to address its degradation in wastewater treatment, with catalytic wet peroxide oxidation (CWPO) being highlighted due to its cost-effectiveness and mild operation. However, developing active and inexpensive catalysts is crucial for CWPO’s eff...
Selective denitrification of a simulated oily wastewater using Janus-structured...
Roman, Fernanda; Sanches, Flávia Kim; Silva, Adriano S.; Díaz de Tuesta, Jose Luis; Marin, Pricila; Machado, Bruno; Serp, Philippe; Silva, AdriánCarbon nanotubes (CNTs) bearing a Janus-like structure were synthesized by chemical vapor deposition considering ethylene and acetonitrile as carbon and nitrogen sources. The developed materials were applied as catalyst in the oxidation of 4-nitrophenol (4-NP) dissolved in a biphasic medium (water/2,2,4-trimeylpentane) simulating a contaminated oily wastewater. The CNT prepared using both ethylene and acetonitr...
Selective oxidation of 4-nitrophenol with H2O2 in a biphasic system by janus-li...
Sanches, Flávia Kim; Roman, Fernanda; Silva, Adriano S.; Díaz de Tuesta, Jose Luis; Silva, Adrián; Faria, Joaquim; Machado, Bruno; Serp, PhilippeThe use of petroleum-based products has increased drastically with the increase in population, resulting in the deposition of oily products in aquatic systems. It is estimated that for each ton of petroleum that undergoes refinement processes, between 0.5 and 1 ton of oily wastewaters are generated, bearing an oil concentration that may reach 40 g L-1 [1,2]. Hazardous pollutants dissolved both in oily and aqueo...
Biphasic oxidative denitrogenation with H2O2 of a simulated fuel using sustaina...
Piccinin, Larissa; Roman, Fernanda; Freitas, Isabella Veronica; Díaz de Tuesta, Jose Luis; Silva, Adrián; Faria, Joaquim; Vieira, Admilson L.The presence of nitrogenated compounds in liquid fuels (e.g. quinoline (QN), azapyrene, pyrrole, indole or carbazole) is associated with a series of environmental and health issues [1], as upon their combustion, noxious NOx gases are formed. Typically, those heteroatoms are removed by hydrodenitrogenation (HDN), a process based on the application of H2 under high temperature and pressure [2]. However, due to th...
Magnetic carbon nanotubes prepared from LDPE, HDPE and PP
Sanches, Lucas Fenato; Silva, Adriano S.; Roman, Fernanda; Silva, Ana P. F.; Díaz de Tuesta, Jose Luis; Silva, Fernando Alves; Silva, AdriánPlastics are among the most generated solid wastes, predominantly composed by polymers, as low-density polyethylene (LDPE), high-density polyethylene (HDPE), and polypropylene (PP).1 This work deals with the preparation of magnetic carbon nanotubes (CNTs) by catalytic chemical vapor deposition (CCVD) at 850 ºC, considering LDPE, HDPE and PP as carbon precursors representative of urban plastic solid waste in a p...
Oxidative denitrogenation of a simulated fuel under a biphasic green system
Roman, Fernanda; Piccinin, Larissa; Freitas, Isabella Veronica; Díaz de Tuesta, Jose Luis; Silva, Adrián; Faria, Joaquim; Vieira, Admilson L.Este trabalho trata da desnitrificação catalítica de um combustível simulado (quinolina (QN) em 2,2,4-trimetilpentano) por oxidação com peróxido de hidrogénio em meio bifásico. Como catalisadores, foram utilizados três materiais: (i) ferro suportado em alumina (Fe/Al2O3) obtido por sol-gel, (ii) nanotubos de carbono (CNT) produzidos através da deposição química em fase de vapor de propileno (PP) sobre o catalis...
Selective oxidation of quinoline in an emulsified system using carbon nanotubes...
Roman, Fernanda; Díaz de Tuesta, Jose Luis; Silva, Adrián; Faria, Joaquim; Gomes, HelderNitrogenated compounds are naturally found in petroleum-based products. Upon their combustion, hazardous gases (NOx) are generated, leading to environmental and health issues. To overcome the downsides related to nitrogen oxides,1 catalytic oxidative denitrogenation (ODN) with H2O2 is currently seen as a suitable alternative to traditional hydrodenitrogenation. In this work, the catalysts for ODN consisted of c...