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The Influence of Nanoparticles on Diesel Engine Performance and Emissions
Published in Lionello Pogliani, Suresh C. Ameta, A. K. Haghi, Chemistry and Industrial Techniques for Chemical Engineers, 2020
Mamdouh Gadalla, Omar Mazen, Hany A. Elazab, Tarek M. Aboul-Fotouh, Fatma H. Ashour
Cerium oxide has been investigated; cerium addition of cerium oxide can result in escaping small amounts of nanoparticle with the exhaust emissions. The studies have shown that cerium oxide can accumulate in the environment especially in the roadside areas. The ability to explore the effect of additive particle size on performance has opened up a new range of potential to improve the performance of internal combustion engines, reduce fuel consumption, and counteract some of the performance compromises currently associated with using biofuels. The main challenge moving forward will be to fully assess the potential environmental impacts of releasing these nanoadditives into the environment and comparing the results with potential improvements to emissions.13,14
Sustainable Nanotechnology Development Using Risk Assessment and Applying Life Cycle Thinking
Published in Jo Anne Shatkin, Nanotechnology, 2017
Nanoscale cerium oxide is now being used commercially for a variety of uses, including as a fuel additive that improves fuel burning and reduces the release of particles from the exhaust of diesel engines. Since 1999, cerium oxide has been used as a diesel fuel additive in the United States (Cassee et al. 2011), and it underwent trials in the United Kingdom in 2004–2006 and is now used there as well. Adding cerium oxide nanoparticles to diesel fuel has been demonstrated to improve fuel efficiency while reducing soot formation (lowering air pollution) and volatile emissions (Energetics 2012; Cassee et al. 2011). In 2001, the Health Effects Institute (HEI) conducted a risk assessment of cerium oxide in fuels, concluding that: Based on the limited data available, toxicity of cerium oxide appears to be small, and cerium oxide might not be of concern when inhaled or ingested at the low levels that would be encountered in the environment.… The absence of more complete information precludes fully assessing the possible health effects of using cerium as a fuel additive.… Considerations are the additive’s ability to reduce harmful emissions, its persistence in the environment, and the feasibility and cost effectiveness of this technology in comparison with other technologies that can achieve these reductions. (HEI 2001)
Overview On Extraction and Separation of Rare Earth Elements from Red Mud: Focus on Scandium
Published in Mineral Processing and Extractive Metallurgy Review, 2018
Ata Akcil, Nazym Akhmadiyeva, Rinat Abdulvaliyev, Pratima Meshram
REEs have a wide range of applications and they are used in many new electronic devices such as mobile phones, screens, high-capacity batteries, permanent magnets for wind power stations, ceramics, etc. Scandium mainly used for the production of lenses and prisms used in film and photographic equipment. Apart from that, it is also used for astronomical purposes. Yttrium is used for the manufacture of LEDs, CRTs, ceramics, computer monitors, temperature sensor, while lanthanum is used for making batteries, electric car batteries, laptop batteries and also for high-tech digital cameras, video cameras, X-ray films, and lasers. Cerium is used for producing the catalysts, metal alloys, optical glass and silicon microprocessors. Similarly, praseodymium is used for pigments, photographic filters and airport signal lenses and neodymium for high-power magnets for the laptop. Thulium is used to make high power magnets for laptops, lasers, while samarium is utilized for making high-temperature magnets. Lutetium finds its application in X-ray phosphor, dysprosium in high-power magnets, lasers and terbium in phosphors for light and displays (Abhilash et al., 2015; Gladyshev et al., 2013, 2015; Massari and Marcello, 2013; Okudan et al., 2015a,b).
Synthesis and electrocatalytic reactivity for water oxidation of two cerium complexes
Published in Journal of Coordination Chemistry, 2018
Tian-Xiang Lan, Xia Zhang, Chang-Neng Chen, Hui-Sheng Wang, Mei Wang, Yu-Hua Fan
In the last 20 years, the unusual chemical characteristics, such as fluorescent, magnetic, redox, and catalytic properties, of lanthanide compounds has been studied extensively [4–6] owing to their unique 4f electrons. Meanwhile, cerium clusters and related materials have been widely applied as catalysts or supports in many areas such as organic synthesis [7], catalytic oxidation [8], and heterogeneous catalytic synthesis [9,10], as well as energy conversion [11]. As we all know, cerium compounds have a very facile redox couple CeIV–CeIII, which enables them to have various electrochemical properties. Besides, ceria possesses the ability of storage, release, and transport oxygen. Ceric ammonium nitrate (CAN, (NH4)2Ce(NO3)6) has been generally used as a very strong water oxidant in homo- [12–14] and heterogeneous [15,16] photocatalytic water oxidation reactions. Furthermore, CeIV ion is also widely applied in water oxidation reactions of ruthenium-complex based systems [17]. However, the electrical reactivity of cerium compounds has been rarely explored. In addition, it was found that heterometallic 3d-4f complexes may display excellent catalytic performance in water oxidation reactions [18,19]. For the reasons above, we synthesized a cerium complex containing manganese ion, a pentanuclear 3d-4f Ce/Mn complex: [MnCe4(dipic)6(H2O)20][Ce(dipic)3]2·7H2O (1) and a cerium only complex [Ce2(H2O)4(O2CMe)6][Ce(H2O)4(NO3)2(O2CMe)]2·2H2O·2MeOH (2) and investigated their electrocatalytic reactivity for water oxidation.
Recovery and Recycling of Cerium from Primary and Secondary Resources- a Critical Review
Published in Mineral Processing and Extractive Metallurgy Review, 2020
Cerium is the light group rare earth element with atomic number 58 and atomic weight 140.116. Cerium is the most common lanthanides found in the Earth’s crust, where it comprises about 0.0046% by weight (Dahle and Arai 2015). There are no ores, which contains only cerium as the metal component. It is found in minerals that include all the other lanthanide elements. The current production of CeO2 is about 54,400 t (32% of REE oxides) (Borra et al. 2017) and its market is expected to register a CAGR of around 8%, during the forecast period of 2019–2024. It is found in many minerals including monazite, bastnäsite, gadolinite, fergusonite, samarskite, xenotime, yttrocerite, cerite and allanite (also known as orthite), etc. Monazite [(Ce, La, Y, Th)PO4] and Bastnäsite [(La, Ce)FCO3] are presently the two more important sources of cerium (Shwe, Soe and Lwin 2008). Table 1 lists the predominant cerium minerals found in various locations along with their composition. Cerium oxides and other cerium compounds are used in catalytic converters and larger-scale equipment to reduce sulfur oxide emissions. Cerium is a diesel fuel additive for micro-filtration of pollutants and promotes more complete fuel combustion for more energy efficiency. It is one of the components of misch metal, which is used extensively in the manufacturing of pyrophoric alloys, making aluminum alloys and in some irons and steels. (Shwe, Soe and Lwin 2008). Cerium is used as a catalyst in automobile and nuclear chemistry, NiMH batteries, FCC catalyst, autocatalyst, petroleum refining, polishing agents, as a component in glass (Habashi 2013). It is also used in car coatings, CFLs, LEDs, LCD backlights, plasma screens, which later becomes a secondary source of cerium recovery (Borra et al. 2017).