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Boron Leaching Control by Heat Treatment and Tannin ImpregnationVerly Lopes, Dercilio Junior 03 May 2019 (has links)
This dissertation aimed to assess whether tannins were able to prevent boron leaching using heat treatment. First, to understand tannin behavior under high temperatures a pilot test was performed. Tannin powder from the Quebracho tree was dissolved into deionized water (DW). Southern yellow pine (SYP) and yellow-poplar (YP) woods were impregnated with tannins under a full cell process. Heat treatment under N2 atmosphere at 190/195/210°C was evaluated for four hours for both species. Mass loss due to heat treatment for wood and tannin as well as radial and tangential shrinkage were calculated. FT-IR spectroscopy and scanning electron microscopy were performed to understand the phenomena. Results indicated that at temperatures above 190°C there was an excessive tannin mass loss with collapse formation on SYP tannin-treated samples as well as changes in the in the spectra. The detailed study used 80 g of tannins and 12 g of DOT into 800 g of DW to attempt preventing boron leaching. SYP and YP samples were impregnated through full cell process and heat treated under N2, at 190°C for four hours. Samples were leached for 15 days. Anti-swelling efficiency was calculated. The resistance of the woods was tested against Gloeophyllum trabeum and Trametes versicolor fungi as well as the subterranean termite Reticulitermes flavipes for leached and unleached samples. The mass loss due to heat treatment was higher in YP than in SYP. The color changed for both woods, turning into much darker after tannin impregnation and heat treatment. All treatments for both species had lower volumetric shrinkage when compared to control as an effect of heat treatment, leading to improvement in dimensional stability. When mixed with tannins and heat treated, DOT remained in wood with leaching reduction of 46.5% and 34.5% for SYP and YP, respectively. After 15 days leaching HT T/DOT samples were classified as resistant (SYP) and highly resistant (YP) to the attack of decay fungi. Heat treated wood had improvement in durability against R. flavipes. HT DOT leached samples had 20.6% mass loss, whereas HT T/DOT 13.8%. Future work with amine-tannin solution should be tested to improve the leaching reduction.
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Extraction of Preservative Components from Treated Wood WasteZhou, Gao 31 August 2012 (has links)
The preservative concentration difference in treated wood was investigated to understand the component distribution; a study of different chemical extractions of treated wood waste was carried out and certain reagents were realized to be feasible to the preservative component removal. During fixation, the preservative components redistributed between earlywood and latewood and concentration gradients at depths also developed. Different solvent extractions of CCA treated wood were tested and ion exchange, chelation and metal dissolving were all mechanisms for component extraction. The transition of Cr(III) to Cr(VI) by oxidizing reagents (NaClO and H2O2) can make possible the direct reuse of extracted chemicals as a preservative. Different reaction factors in the oxidant extractions were compared and higher pHs significantly improved the oxidizing capability of the reagents and CCA component removal. Fresh and aged CCA treated wood generally responsed similarly to the oxidant extractions. However, arsenic in aged wood was more difficult to be removed by NaClO, while, H2O2 was more efficient to extract CCA components from aged wood than fresh wood. Monoethanolamine (Mea) efficiently extracted copper (above 90%) from ACQ treated wood and the formation of stable neutral Cu(Mea)2 in sufficient Mea solution is the main mechanism for Mea extraction. Little wood structure degradation occurred during the process. Mea (10%~15%) extraction was fast and the effect of temperature was insignificant. Cu diffusion in the longitudinal direction was the most significant compared to other wood directions. To further promote Mea extraction, repeated extraction (batch-based and column-based) was performed and proved to be more efficient, feasible and economical than one-time extraction. Column-based continuous Mea extraction showed both high Cu removal (up to 99%) and Cu accumulation in the extract. After the preservative treated wood waste is decontaminated significantly, the extract solution can be reused by directly mixing with the preservative treating solution, which is the most straightforward procedure for the recycling of chemicals removed from the preservative treated wood.
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Extraction of Preservative Components from Treated Wood WasteZhou, Gao 31 August 2012 (has links)
The preservative concentration difference in treated wood was investigated to understand the component distribution; a study of different chemical extractions of treated wood waste was carried out and certain reagents were realized to be feasible to the preservative component removal. During fixation, the preservative components redistributed between earlywood and latewood and concentration gradients at depths also developed. Different solvent extractions of CCA treated wood were tested and ion exchange, chelation and metal dissolving were all mechanisms for component extraction. The transition of Cr(III) to Cr(VI) by oxidizing reagents (NaClO and H2O2) can make possible the direct reuse of extracted chemicals as a preservative. Different reaction factors in the oxidant extractions were compared and higher pHs significantly improved the oxidizing capability of the reagents and CCA component removal. Fresh and aged CCA treated wood generally responsed similarly to the oxidant extractions. However, arsenic in aged wood was more difficult to be removed by NaClO, while, H2O2 was more efficient to extract CCA components from aged wood than fresh wood. Monoethanolamine (Mea) efficiently extracted copper (above 90%) from ACQ treated wood and the formation of stable neutral Cu(Mea)2 in sufficient Mea solution is the main mechanism for Mea extraction. Little wood structure degradation occurred during the process. Mea (10%~15%) extraction was fast and the effect of temperature was insignificant. Cu diffusion in the longitudinal direction was the most significant compared to other wood directions. To further promote Mea extraction, repeated extraction (batch-based and column-based) was performed and proved to be more efficient, feasible and economical than one-time extraction. Column-based continuous Mea extraction showed both high Cu removal (up to 99%) and Cu accumulation in the extract. After the preservative treated wood waste is decontaminated significantly, the extract solution can be reused by directly mixing with the preservative treating solution, which is the most straightforward procedure for the recycling of chemicals removed from the preservative treated wood.
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Metal Loss From Treated Wood Products in Contact With Municipal Solid Waste Landfill LeachateDubey, Brajesh, Townsend, Timothy, Solo-Gabriele, Helena 15 March 2010 (has links)
The research presented in this paper evaluates the potential impact of municipal solid waste (MSW) landfill leachate quality on the loss of metals from discarded treated wood during disposal. The loss of arsenic (As), chromium (Cr), copper (Cu), and boron (B) from several types of pressure-treated wood (CCA: chromated copper arsenate, ACQ: alkaline copper quaternary, CBA: copper boron azole, and DOT: disodium octaborate tetrahydrate) using leachate collected from 26 MSW landfills in Florida was examined. The toxicity characteristic leaching procedure (TCLP), the synthetic precipitation leaching procedure (SPLP), and California's waste extraction test (WET) were also performed. The results suggested that loss of preservative components was influenced by leachate chemistry. Copper loss from CCA-, ACQ- and CBA-treated wood was similar in magnitude when in contact with landfill leachates compared to synthetic TCLP and SPLP solutions. Ammonia was found as one of the major parameters influencing the leaching of Cu from treated wood when leached with MSW landfill leachates. The results suggest that disposal of ACQ- and CBA-treated wood in substantial quantity in MSW landfills may elevate the Cu concentration in the leachate; this could be of potential concern, especially for a bioreactor MSW landfill in which relatively higher ammonia concentrations in leachate have been reported in recent literature. For the As, Cr and B the concentrations observed with the landfill leachate as the leaching solutions were over a range from some sample showing the concentrations below and some showing above the observed value from corresponding SPLP and TCLP tests. In general the WET test showed the highest concentrations.
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The Feasibilty of Recycling CCA Treated Wood From Spent Residential DecksBailey, David Samuel 27 March 2003 (has links)
The amount of CCA treated wood being removed from spent residential decks is increasing at a tremendous rate. While most spent CCA treated wood is being disposed in landfills, further useful and environmentally beneficial alternatives have to be met. This research estimated the percentage of recoverable lumber from spent CCA decks that can be recycled into other usable products. Six residential decks were removed from service, by either demolition or deconstruction procedures. It was found that 86% of the CCA treated wood from the residential decks could be recovered as reusable CCA treated lumber. It was also found that deconstruction of a residential deck, rather than demolition, was not a factor in the volume of CCA treated wood recovered. Chemical and mechanical properties of the removed CCA treated wood were also analyzed. The chemical retention of the deck material proved that most of the spent CCA treated wood could be used in above ground applications. The stiffness of spent CCA treated wood from residential decks was approximately equal to that of recently treated CCA wood. The strength properties were slightly lower than recently treated CCA wood probably due mainly to physical and climatic degradation. Products were then produced that could be successfully utilized by recycling centers or community and government organizations. Products manufactured included, pallets, picnic tables, outdoor furniture, residential decks, and landscaping components. Waste management, recycling, and government organizations were interviewed to determine what markets and barriers exist for recycled CCA treated products. Most landfill and recycling facilities do not currently sort or recycle CCA treated wood, citing the main reason as a lack of a viable market. Potential users were interested in the material but citied they did not know where to locate the material. A communication barrier exists between the waste management industry, recyclers, and users; which is preventing the successful recycling of CCA treated wood from spent residential decks. / Master of Science
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Valorisation énergétique des déchets de bois traités par voies thermochimiques (pyrolyse et hydroliquéfaction) : Application aux bois traités aux sels de CCB (cuivre-chrome-bore) / Energy recovery of CCB-treated wood using thermo chemical processes (pyrolysis and hydroliquefaction) : Application to CCB-treated woodSenga kiesse, Silao Esperance 02 April 2013 (has links)
Les déchets de bois traités représentent 27% du gisement des déchets dangereux en France. Ces déchets sont incinérés dans des installations classées pour la protection de l’environnement (ICPE). Néanmoins, leur incinération nécessite des équipements robustes et coûteux pour le lavage des gaz et des fumées toxiques. Dans ce contexte, le présent travail a pour objectif d’élaborer et de mette en oeuvre d’autres voies de valorisation énergétique des déchets de bois traités par des procédés thermochimiques. Pour cela, les procédés de pyrolyse et d’hydroliquéfaction ont été mis en oeuvre principalement pour la valorisation énergétique des déchets de bois traités aux sels de CCB (cuivre-chrome-bore) qui représentent 8750 tonnes/an en France. Le bois imprégné de sels de CCB dans nos laboratoires conformément au traitement industriel, a été étudié afin de maîtriser le bilan des métaux dans les différents produits de pyrolyse et d’hydroliquéfaction. Une étude préliminaire de son comportement thermique a été menée par analyse thermogravimétrique dans le but de déterminer l’intervalle de température effectif à sa dégradation massique. Dans cet intervalle de température, les paramètres expérimentaux de pyrolyse lente ont été optimisés pour piéger les métaux dans le charbon. Par la suite, une étude paramétrique par la méthode des plans d’expérience a été réalisée pour la conversion du charbon en bio-huile. De plus, l’optimisation de l’hydroliquéfaction pour la conversion du bois traité en bio-huile a été effectuée. Les résultats montrent que les métaux initialement présents dans le bois traité sont répartis entre la bio-huile et le coke quelque soit la voie de valorisation énergétique empruntée (hydroliquéfaction/pyrolyse+hydroliquéfaction). Cependant la bio-huile présente des caractéristiques proches de celles des biodiesels. L’utilisation de catalyseur au cours de l’hydroliquéfaction du charbon de pyrolyse améliore non seulement la qualité de la bio-huile mais aussi le bilan d’énergie sur le procédé. / The amount of treated-wood waste was estimated to 27% of the deposit of hazardous waste in France. These wastes are incinerated in specials incineration plants “installations classées pour la protection de l’environnement”. However, incineration produces harmful residues and contaminated gases released into the atmosphere inevitably. In this context, this work aims to develop and implement other ways of energy recovery from treated-wood waste using thermo-chemical processes. For this, the pyrolysis and hydroliquefaction processes were performed for energy recovery from CCB treated wood waste (copper-chromium-boron) representing 8750 t / year in France. Natural wood were impregnated with salts of CCB in our laboratories according to industrial processing to control the balance of metals in pyrolysis and hydroliquefaction products. A preliminary study was carried out by thermogravimetric analysis in order to determine the temperature range for effective mass degradation of CCB treatedwood. In this temperature range, the experimental parameters of slow pyrolysis have been optimized to concentrate metals in charcoal. Subsequently, a parametric study was conducted by the method of experimental design for the conversion of coal into bio-oil. In addition, the optimization of the conversion hydroliquefaction treated wood into bio-oil was performed. The results show that the metals initially present in the treated wood are divided between the bio-oil and coke whatever the processes energy recovery used (hydroliquefaction / pyrolysis + hydroliquefaction). However, the immediate characteristics of bio-oil and biodiesel are quite similar. The use of catalyst during charcoal conversion improves the quality of the bio-oil but also the energy balance of the process.
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Utilização de técnicas de caracterização de superfícies em madeiras tratadas termicamente / Surface Characterization Techniques applied in heat-treated woodOliveira, Rodrigo Marques de 30 June 2009 (has links)
Este trabalho tem como objetivo estudar as mudanças das propriedades de superfícies e estruturais ocorridas em amostras de madeira termorretificadas. Duas espécies foram escolhidas para representar cada um dos grupos das madeiras: folhosas e coníferas. As amostras foram tratadas termicamente no intervalo de temperaturas entre 100 e 200 C, em atmosfera com ar. A variação da molhabilidade das espécies foi estudada a partir do ângulo de contato medido pelo método da gota séssil e monitorado no tempo ao longo de um ano. As amostras tratadas termicamente apresentaram ângulos de contato maiores, devido ao aumento nas suas características de hidrofobicidade. As técnicas de espectroscopia de infravermelho por refletância total atenuada e de espalhamento de raios-X foram utilizadas sendo possível detectar um aumento na cristalinidade da superfície das amostras, então responsável por esse aumento na hidrofobicidade. A técnica de FTIR permitiu distinguir os grupos funcionais das amostras de madeira (folhosas e coníferas), mesmo sendo obtidos espectros com baixa intensidade de sinal. Medidas de retratibilidade foram feitas nas amostras e as folhosas foram as que apresentaram maiores valores de retratibilidade volumétrica. Para tratamentos térmicos em mais altas temperaturas, foi observada uma redução considerável na retratibilidade volumétrica das amostras. Durante a secagem da madeira, o Eucalyptus grandis (cerne) foi o que apresentou uma maior contração volumétrica e a Araucaria angustifolia (cerne), a menor. Quando tratada em altas temperaturas, o Eucalyptus grandis (cerne) apresentou uma maior contração volumétrica e o Pinus elliotti, uma pequena expansão. A perda de massa também foi monitorada durante o tratamento térmico para todas as espécies. As folhosas apresentaram uma maior redução dos valores de massa em função do tratamento térmico, comparativamente às coníferas. O sistema CIE Lab de cor foi utilizado para se classificar as amostras termorretificadas. Uma análise multivariada de dados foi feita para acompanhar como cada parâmetro determinante da cor variava com a espécie e com o tratamento. Um dendrograma foi gerado, unindo espécies e tratamentos que apresentavam aproximadamente uma mesma cor final das amostras de madeira, contribuindo para as etapas de caracterização. / The main aim of this work was the characterization of changes of properties occurred on the surface and structure of heat-treated wood in response to thermal treatments. In order to cover different types of heat-treated wood, two species were elected as models for two great groups of woods, the so-called hard and soft woods. The samples were thermally treated in temperature range from 100 to 200 C under air atmosphere, and the water contact angle was periodically measured with the sessile drop method during one year. High values of contact angle were observed for the samples after the thermal treatment, reflecting their increased hydrophobicity. Probably, the reason for such increased hydrophobicity is the increase in the crystallinity of the samples, probed by ATR-infrared spectroscopy and X-ray scattering analyses. Even with FTIR analysis showing low-intensity bands, it was possible to distinguish between woods from the two groups, hard and soft woods by using this technique. Measurements of wood shrinkage were also carried out for the samples, with hard wood showing higher values of volumetric shrinkage. Moreover, for thermal treatments at higher temperatures, the volumetric shrinkage of the wood sampes was markedly reduced. During the drying process, the highest and lowest values of volumetric contraction were obtained for Eucalyptus grandis (heartwood) and Araucaria angustifólia (heartwood), respectively. Surprisingly, when treated at higher temperatures the samples from Pinus elliotti showed a small expansion, but Eucalyptus grandis (heartwood) was still the more contractile wood. Also, during the thermal treatment, the loss of mass was evaluated for all the samples. Hard woods exhibited a large reduction of mass in response to the heating in comparison with soft woods, with no exceptions. The CIE Lab system was used to categorize the heat-treated woods. A multivariate data analysis was used to monitor each color parameter, and its dependence on the type of heat treatment. From these analyses, a dendogram was generated, and the samples with almost the same final color were grouped regarding the species and type of treatment.
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Emprego de resíduos de Pinus sp tratado com preservante CCB na produção de chapas de partículas homogêneas utilizando resina poliuretana à base de mamona / Use of CCB treated Pinus sp residues in particleboard production employing polyurethane resin based on castor oilBertolini, Marília da Silva 23 February 2011 (has links)
O CCB (sais de cromo, cobre e boro) surgiu como alternativa ao CCA, apresentando menor toxicidade ao meio ambiente e em muitos casos conferindo excelentes propriedades mecânicas à madeira. Estima-se que, de 15 a 20% (aproximadamente 240 mil \'M POT.3\'/ano) da madeira tratada no Brasil atualmente sejam resíduos, considerando-se apenas aqueles provenientes do seu beneficiamento, desconsiderando os produtos pós-consumo. Por outro lado, o Brasil possui excelentes condições para a produção dos painéis aglomerados, com produção estimada atualmente em 2,5 milhões \'M POT.3\'/ano. Observando o crescimento do mercado de painéis à base de madeira e a constante busca por produtos sustentáveis, este trabalho teve como objetivo principal a análise da viabilidade de produção de chapas de partículas, empregando-se resíduos de Pinus sp tratado com preservante CCB e resina poliuretana à base de mamona. Foram variados parâmetros de produção para obtenção de melhores condições de processo, sendo estes: quantidade de partículas, com 1300g e 1400g; teor de adesivo, de 12% e 15% e; tempo de prensagem, de 10 e 12 minutos. Caracterizaram-se as partículas empregadas quanto as suas propriedades físicas e morfológicas, além da análise dos painéis quanto às características físico-mecânicas, segundo NBR 14810-3 (2006), submetendo-se também amostras com melhores desempenhos ao Envelhecimento Artificial Acelerado, conforme ASTM G155 (1999) e análise da morfologia, por meio de ensaios de Microscopia Eletrônica de Varredura (MEV) e Porosimetria por Intrusão de Mercúrio. Determinou-se também a retenção dos ingredientes ativos de preservante nas partículas e chapas, para avaliação de possíveis perdas na retenção devido ao processo de prensagem. Os resultados apontaram para excelentes propriedades físicas e mecânicas das chapas de partículas, em alguns casos em média 50% superiores ao estipulado pela norma brasileira em questão e superiores aos requisitos das normas internacionais. Assim, ficou evidenciada a viabilidade de produção dos painéis com os insumos estudados bem como seu potencial de emprego para as finalidades compatíveis com produtos desta natureza. / CCB (chromium, copper and boron sales) has risen as an alternative to CCA, because of its toxicity level and, in several cases, conferring high properties to treated wood. In Brazil, some evaluations show that nearly 15 to 20% (something like 240.000 \'M POT.3\'/year) of this wood are residues generated by processing phases, without taking in account pos-used product. Besides, Brazilian particleboard industry produces 2.500.000 \'M POT.3\'/year. Observing wood based panels demand improvement and sustainable products search, the aim of this work is to confirm feasibility of producing particleboards with CCB treated Pinus sp residues and polyurethane resin based on castor oil. Different production parameters were employed in order to optimize process conditions, like: particles (1300g and 1400g); adhesive percentage (12 and 15%); pressure time (10 and 12 minutes). Particles were characterized by their physical and morphological properties. Panels\' performance was determined based on their physical and mechanical properties, as prescript in Brazilian Code NBR 14810-3 (2006). Special specimens were used in order to evaluate influence of accelerated aging as proposed in ASTM G155 (1999). Morphological aspects were analyzed by Scanning Electron Microscopy (SEM) and Mercury Intrusion Porosimetry. Active ingredients retention was also determined to establish casual lost after producing process. Results show excellent physical and mechanical properties, some of them 50% higher than NBR14810-3 and international codes requirements. Feasibility of producing particleboards like those studied was demonstrated as well as potential of their employing in same uses of commercial boards.
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Diffuse emissions from goods - influences on some societal end productsAmneklev, Jennie January 2015 (has links)
End products of society (e.g. sewage sludge and incineration ashes) can be used as indicators of the use of chemicals in consumer goods. Through upstream work the sources of substances released from goods may be identified before the emissions reach the end products. This thesis is a result of five studies, of which four were conducted using substance flow analyses (SFA) for silver (Ag), bismuth (Bi) and copper (Cu) reaching sewage sludge. The fifth is an SFA that explores the implications of the presence of As (from CCA-treated wood) in ashes. These studies helped fulfil the specific and overall aims of the thesis; to contribute to the general knowledge on diffuse emissions reflected in end products, by examining emissions of some heavy metals from various societal goods and the implications for end products, in this case sewage sludge and, to some extent, ashes. The results from the studies, of which four had Stockholm as a study object, show the urban flows and accumulated amounts (stocks) of the heavy metals. The largest sources of the metals Ag, Bi and Cu in sewage sludge were identified to be textiles (Ag), cosmetics (Bi) and brake linings (Cu). For As (in CCA-treated wood) and Cu updated SFAs were performed and compared with earlier studies in order to follow the development and changes in flows over time. The current use of the heavy metals studied can also be seen as a loss of resources, and as the metals should ideally be recovered as a part of a circular economy, urban and landfill mining as well as recycling are alternatives that need further exploring. The legislation of chemicals in consumer goods was identified as an important step in handling corresponding diffuse emissions.
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Emprego de resíduos de Pinus sp tratado com preservante CCB na produção de chapas de partículas homogêneas utilizando resina poliuretana à base de mamona / Use of CCB treated Pinus sp residues in particleboard production employing polyurethane resin based on castor oilMarília da Silva Bertolini 23 February 2011 (has links)
O CCB (sais de cromo, cobre e boro) surgiu como alternativa ao CCA, apresentando menor toxicidade ao meio ambiente e em muitos casos conferindo excelentes propriedades mecânicas à madeira. Estima-se que, de 15 a 20% (aproximadamente 240 mil \'M POT.3\'/ano) da madeira tratada no Brasil atualmente sejam resíduos, considerando-se apenas aqueles provenientes do seu beneficiamento, desconsiderando os produtos pós-consumo. Por outro lado, o Brasil possui excelentes condições para a produção dos painéis aglomerados, com produção estimada atualmente em 2,5 milhões \'M POT.3\'/ano. Observando o crescimento do mercado de painéis à base de madeira e a constante busca por produtos sustentáveis, este trabalho teve como objetivo principal a análise da viabilidade de produção de chapas de partículas, empregando-se resíduos de Pinus sp tratado com preservante CCB e resina poliuretana à base de mamona. Foram variados parâmetros de produção para obtenção de melhores condições de processo, sendo estes: quantidade de partículas, com 1300g e 1400g; teor de adesivo, de 12% e 15% e; tempo de prensagem, de 10 e 12 minutos. Caracterizaram-se as partículas empregadas quanto as suas propriedades físicas e morfológicas, além da análise dos painéis quanto às características físico-mecânicas, segundo NBR 14810-3 (2006), submetendo-se também amostras com melhores desempenhos ao Envelhecimento Artificial Acelerado, conforme ASTM G155 (1999) e análise da morfologia, por meio de ensaios de Microscopia Eletrônica de Varredura (MEV) e Porosimetria por Intrusão de Mercúrio. Determinou-se também a retenção dos ingredientes ativos de preservante nas partículas e chapas, para avaliação de possíveis perdas na retenção devido ao processo de prensagem. Os resultados apontaram para excelentes propriedades físicas e mecânicas das chapas de partículas, em alguns casos em média 50% superiores ao estipulado pela norma brasileira em questão e superiores aos requisitos das normas internacionais. Assim, ficou evidenciada a viabilidade de produção dos painéis com os insumos estudados bem como seu potencial de emprego para as finalidades compatíveis com produtos desta natureza. / CCB (chromium, copper and boron sales) has risen as an alternative to CCA, because of its toxicity level and, in several cases, conferring high properties to treated wood. In Brazil, some evaluations show that nearly 15 to 20% (something like 240.000 \'M POT.3\'/year) of this wood are residues generated by processing phases, without taking in account pos-used product. Besides, Brazilian particleboard industry produces 2.500.000 \'M POT.3\'/year. Observing wood based panels demand improvement and sustainable products search, the aim of this work is to confirm feasibility of producing particleboards with CCB treated Pinus sp residues and polyurethane resin based on castor oil. Different production parameters were employed in order to optimize process conditions, like: particles (1300g and 1400g); adhesive percentage (12 and 15%); pressure time (10 and 12 minutes). Particles were characterized by their physical and morphological properties. Panels\' performance was determined based on their physical and mechanical properties, as prescript in Brazilian Code NBR 14810-3 (2006). Special specimens were used in order to evaluate influence of accelerated aging as proposed in ASTM G155 (1999). Morphological aspects were analyzed by Scanning Electron Microscopy (SEM) and Mercury Intrusion Porosimetry. Active ingredients retention was also determined to establish casual lost after producing process. Results show excellent physical and mechanical properties, some of them 50% higher than NBR14810-3 and international codes requirements. Feasibility of producing particleboards like those studied was demonstrated as well as potential of their employing in same uses of commercial boards.
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