PAULO ERNESTO DE OLIVEIRA LAINETTI
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Artigo IPEN-doc 26391 Thorium and lithium in Brazil2019 - OLIVEIRA, GLAUCIA A.C. de; LAINETTI, PAULO E.O.; BUSTILLOS, JOSE O.W.V.; PIRANI, DEBORA A.; BERGAMASCHI, VANDERLEI S.; FERREIRA, JOAO C.; SENEDA, JOSE A.Brazil has one of the largest reserves of thorium in the world, including rare earth minerals. It has developed a great program in the field of nuclear technology for decades, including facilities to produced oxides to microspheres and thorium nitrates. Nowadays, with the current climate change, it is necessary to reduce greenhouse gas emissions, one of this way is exploring the advent of IV Generation reactors, molten salt reactors, that using Thorium and Lithium. Thorium's technology is promising and has been awaiting the return of one nuclear policy that incorporates its relevance to the necessary levels, since countries like the BRICS (without Brazil) have been doing so for years. Brazil has also been developing studies on the purification of lithium, and this one associated to thorium, are the raw material of the molten salt reactors. This paper presents a summary of the thorium and lithium technology that the country already has, and its perspectives to the future.Artigo IPEN-doc 24020 Prospective thorium fuels for future nuclear energy generation2017 - LAINETTI, PAULO E.O.Artigo IPEN-doc 23519 Thorium and its future importance for nuclear energy generation2016 - LAINETTI, PAULO E.O.Thorium was discovered in 1828 by the Swedish chemist Jons J. Berzelius. Despite some advantages over uranium for use in nuclear reactors, its main use, in the almost two centuries since its discovery, thorium was restricted to use for gas mantles, especially in the early 20th century. In the beginning of the nuclear era, many countries had interested on thorium, particularly during the 1950-1970 period. There are about 435 nuclear reactors in the world nowadays. They need more than 65,000 tons of uranium yearly. The future world energy needs will increase and, even if we assumed a conservative contribution of nuclear generation, there will be a significant increasing in the uranium prices occur, taking into account that uranium, as used in the present thermal reactors, is a finite resource. Thorium is nearly three times more abundant than uranium in the Earth’s crust. Despite thorium is not a fissile material, 232Th can be converted to 233U (fissile) more efficiently than 238U to 239Pu. Besides this, since it is possible to convert thorium waste into non-radioactive elements, thorium is an environment-friendly alternative energy source. Thorium fuel cycle is also inherently resistant to proliferation. Some papers evaluate the thorium resources in Brazil over 1,200,000 metric t. Then, the thorium alternative must be seriously considered in Brazil for strategic reasons. In this paper a brief history of thorium is presented, besides a review of the world thorium utilization and a discussion about advantages and restrictions of thorium use.Artigo IPEN-doc 23509 Decommissioning of uranium pilot plants at IPEN-CNEN/SP: facilities dismantling, decontamination and reuse as new laboratories for strategic programs2016 - LAINETTI, PAULO E. de O.; FREITAS, ANTONIO A. de; VASQUES, FRANCISCO M.F.; FERREIRA, ROBSON de J.; COTRIM, MARYCEL E.B.; PIRES, MARIA A.F.From beginning of 90’s, the Brazilian nuclear policy has been changed radically. This determined the interruption of most R&D fuel cycle activities and the facilities shutdown at Nuclear and Energetic Research Institute (IPEN). The existence of those facilities also implicated in the need of constant surveillance, representing additional obligations, costs and problems. The reasons to promote the dismantling of the IPEN’s Nuclear Fuel Cycle Pilot Plants elapsed mainly from the need of physical space for new activities, since the R&D in the nuclear fuel cycle area were interrupted. In the last decade, IPEN has changed its “nuclear profile” to a “comprehensive and multidisciplinary profile”. With the end of most nuclear fuel cycle activities, the former facilities were distributed in four different centers. Each center has adopted a different strategy and priority to face the D&D problem. The available resources depend on the specific program in each area’s development (resources available from other sources, not only from Brazilian National Nuclear Energy Commission (CNEN). One of those new activities is the IPEN’s Environmental Program. This paper describes the procedures, problems faced and results related to the reintegration of the former pilot plant areas as new laboratories of the Chemical and Environmental Technology CenterCQMA of the IPEN.Artigo IPEN-doc 23511 Use of dopants for thoria sintering temperature reduction-characterization of THO22016 - TAKIISHI, HIDETOSHI; GENOVA, LUIS A.; CAVALHEIRA, ELTON D.; COTRIM, MARYCEL B.; SANTOS, WILSON; LAINETTI, PAULO E.O.Thorium is nearly three times more abundant than uranium in the Earth’s crust. Some papers evaluate the thorium resources in Brazil over 1,200,000 metric t. These figures mean that the country is probably the biggest thorium resource in the world, with only part of the territory prospected. Nevertheless, Brazil has not a research program for use of thorium in nuclear reactors, even having dedicated special attention to the subject in the beginning of its nuclear activities, in the fifties and sixties. From 1985 until 2003 IPEN operated a pilot plant for thorium nitrate production and purification, used by Brazilian industry for production of gas mantles. This facility produced over 170 metric t of thorium nitrate. Despite the non-nuclear application, the pilot plant was unique in the southern hemisphere. On the other hand, Brazil has the biggest world niobium resources. The Brazilian thorium and niobium resources added to the predictable future importance of alternative fissile materials have motivated this research, since uranium is a finite resource if used in the present thermal nuclear reactors. Besides this, thorium oxide is an important nuclear reactor material. It is a refractory oxide and its ceramic fabrication process involves a very high temperature sintering treatment considering that thoria melting point is very high (3,650 K). Cations of elements of the group VB (V, Nb and Ta) have a known effect in the reduction of thoria sintering temperature. IPEN has initiated an investigation about the use of niobium as a dopant for thoria sintering temperature reduction. The thoria used in the research was produced in the IPEN’s pilot plant and different amounts of niobium oxide (Nb2O5) will be added to thoria by different routes. The powders will be compressed and the compacted pellets will be sintered at different temperatures. The influence of the different parameters in the density of sintered pellets is being investigated. This paper presents the chemical and physical characterization for the thoria used in the investigation.Artigo IPEN-doc 21084 Thorium and its future importance for nuclear energy generation2015 - LAINETTI, PAULO E.O.Artigo IPEN-doc 21077 Use of dopants for thoria sintering temperature reduction - characterization of ThOsub(2)2015 - TAKIISHI, HIDETOSHI; GENOVA, LUIS A.; CAVALHEIRA, ELTON D.; COTRIM, MARYCEL B.; SANTOS, WILSON R.; LAINETTI, PAULO E.O.Artigo IPEN-doc 20546 Review of brazilian activities related to the thorium fuel cycle and production of thorium compounds at IPEN-CNEN/SP2014 - LAINETTI, PAULO E. de O.; FREITAS, ANTONIO A. de; MINDRISZ, ANA C.Resumo IPEN-doc 02853 Processamento termico ao ar de pos de Usub(3)Osub(8) por microondas para aplicacoes em dispersoes utilizadas em combustiveis nucleares1996 - FURLAN NETO, A.; FREITAS, C.T.; LAINETTI, P.E.O.Artigo IPEN-doc 13964 Decommissioning of nuclear fuel cycle facilities in the IPEN-CNEN/SP2007 - LAINETTI, P.E.O.