The production of a carbon-coated alumina foam

Journal of Nanomaterials

Ngila

Mamba

2015

216

The presence of both organic and inorganic pollutants in water due to industrial, agricultural, and domestic activities has led to the global need for the development of new, improved, and advanced but effective technologies to effectively address the challenges of water quality. It is therefore necessary to develop a technology which would completely remove contaminants from contaminated waters. TiO2(titania) nanocatalysts have a proven potential to treat “difficult-to-remove” contaminants and thus are expected to play an important role in the remediation of environmental and pollution challenges. Titania nanoparticles are intended to be both supplementary and complementary to the present water-treatment technologies through the destruction or transformation of hazardous chemical wastes to innocuous end-products, that is, CO2and H2O. This paper therefore explores and summarizes recent efforts in the area of titania nanoparticle synthesis, modifications, and application of titania nanoparticles for water treatment purposes.

Section: Carbon-coveredmentioning

confidence: 99%

Section: Applications Of Cca Supportsmentioning

confidence: 99%

Recent Developments in Environmental Photocatalytic Degradation of Organic Pollutants: The Case of Titanium Dioxide Nanoparticles—A Review

Journal of Nanomaterials

Ngila

Mamba

2015

216

“…30,31 Recently, CCA supports have been used as a high surface area packing material for high-performance liquid chromatography 32 and have also been prepared in various forms such as carbon-coated alumina foams. 33 CCA-supported catalysts have hardly been used in remediation of environmental burdens. According to literature, only nanosilver catalyst has been supported on CCA to monitor microorganisms in drinking water.…”

Section: Introductionmentioning

confidence: 99%

“…CCA supports have been used as supports for hydrotreating catalysts − and ammonia synthesis. , Recently, CCA supports have been used as a high surface area packing material for high-performance liquid chromatography and have also been prepared in various forms such as carbon-coated alumina foams . CCA-supported catalysts have hardly been used in remediation of environmental burdens.…”

Section: Introductionmentioning

confidence: 99%

Effect of Metal Ions (Ag, Co, Ni, and Pd) on the Visible Light Degradation of Rhodamine B by Carbon-Covered Alumina-Supported TiO₂ in Aqueous Solutions

Mishra

et al. 2013

Ind. Eng. Chem. Res.

Metal-ion (Ag, Co, Ni, and Pd) doped TiO2 nanocatalysts were successfully embedded on carbon-covered alumina supports. The CCA-embedded catalysts were crystalline and had a high surface area compared to the free metal-ion doped titania nanocatalysts while they still retained the anatase phase of the core TiO2. These catalysts were photocatalytically active under solar light irradiation. Rhodamine B was used as a model pollutant and the reactivity followed a pseudo-first-order reaction kinetics. The reaction rate of the CCA-supported catalysts was Pd > Ag > Co > Ni. Among the ratios of the CCA:catalyst used, it was found that the 1:1 ratio had the fastest reaction rate, followed by the 1:2 ratio, while the 2:1 ratio exhibited the lowest reaction rate. The CCA/metal-ion doped titania were found to have photocatalytic activities comparable with those of CCA-supported titania.

“…Recently, supports have found a lot of useful applications. For instance, CCA been used as a high surface area packing material for high performance liquid chromatography (Paek et al 2010), and has also been prepared in various forms like carbon-coated alumina foams (Jana and Ganesan 2011). CCA-supported catalysts have hardly been used in remediation of environmental burdens.…”

mentioning

confidence: 99%

Synthesis and characterization of carbon-covered alumina (CCA) supported TiO2 nanocatalysts with enhanced visible light photodegradation of Rhodamine B

Nanotechnology for Sustainable Development

Mishra

et al. 2012

The anatase phase of titania (TiO 2 ) nanophotocatalysts was prepared using a modified sol gel process and thereafter embedded on carbon-covered alumina supports. The carbon-covered alumina (CCA) supports were prepared via the adsorption of toluene 2,4-diisocyanate (TDI) on the surface of the alumina. TDI was used as the carbon source for the first time for the carbon-covered alumina support system. The adsorption of TDI on alumina is irreversible; hence, the resulting organic moiety can undergo pyrolysis at high temperatures resulting in the formation of a carbon coating on the surface of the alumina. The TiO 2 catalysts were impregnated on the CCA supports. X-ray diffraction analysis indicated that the carbon deposited on the alumina was not crystalline and also showed the successful impregnation of TiO 2 on the CCA supports. In the Raman spectra, it could be deduced that the carbon was rather a conjugated olefinic or polycyclic hydrocarbons which can be considered as molecular units of a graphitic plane. The Raman analysis of the catalysed CCAs showed the presence of both the anatase titania and D and G band associated with the carbon of the CCAs. The scanning electron microscope micrographs indicated that the alumina was coated by a carbon layer and the energy dispersive X-ray spectra showed the presence of Al, O and C in the CCA samples, with the addition of Ti for the catalyst impregnated supports. The Brunauer Emmet and Teller surface area analysis showed that the incorporating of carbon on the alumina surface resulted in an increase in surface area, while the impregnation with TiO 2 resulted in a further increase in surface area. However, a decrease in the pore volume and diameter was observed. The photocatalytic activity of the nanocatalysts was studied for the degradation of Rhodamine B dye. The CCA-TiO 2 nanocatalysts were found to be more photocatalytically active under both visible and UV light irradiation compared to the free TIO 2 nanocatalysts.