EFFICIENCY OF BURNT OIL AS WOOD PRESERVATIVE SUBMITTED TO FIELD DETERIORATION TESTS

EFICIENCIA DO OLEO QUEIMADO COMO PRESERVATIVO DE MADEIRAS SUBMETIDAS A ENSAIOS DE DETERIORACAO DE CAMPO O objetivo desse estudo foi avaliar a eficiencia do oleo queimado como preservativo de madeiras de Trattinnickia rhoifolia Willd. submetidas a ensaios de deterioracao de campo. Os tratamentos preservativos com oleo queimado foram realizados pelo metodo de imersao simples considerando dois fatores de variacao: viscosidade do oleo (SAE 10 e SAE 15) e tempo de imersao (3 min, 3 h e 24 h). A eficiencia dos tratamentos preservativos foi avaliada por meio da taxa de retencao do produto oleoso, quantificacao da lixiviacao apos exposicao em campo e perda de massa causada pela deterioracao biologica. Adicionalmente, foi empregada a tecnica de colorimetria para avaliacao do escurecimento causado pelo tratamento preservativo e no monitoramento da alteracao da cor superficial da madeira devido a lixiviacao pela exposicao a campo. Com base nos resultados pode-se concluir que o tratamento preservativo com oleo queimado foi eficiente, de modo a proporcionar as madeiras uma maior resistencia biologica, com destaque para o uso do oleo de menor viscosidade (SAE 10). As maiores taxas de retencao e menores perdas de massa devido a deterioracao biologica foram obtidas ao empregar o oleo queimado SAE 10, por outro lado tambem apresentaram as maiores taxas de lixiviacao. Palavras-chave: preservacao da madeira, imersao simples, preservativo oleoso, madeira tropical. ABSTRACT The objective of this study was to evaluate the efficiency of oil burned as a wood preservative of Trattinnickia rhoifolia Willd submitted to field deterioration tests. The preservatives treatments with burnt oil were performed by the simple immersion method considering two variation factors: oil viscosity (SAE 10 and SAE 15) and immersion time (3 min, 3 h and 24 h). The effectiveness of the preservative treatments was evaluated through oily product retention rate, quantification of leaching after exposure in the field and mass loss caused by biological deterioration. Additionally, the colorimetric technique was used to assess the darkening caused by preservative treatment and monitoring of the change of surface color of the wood due to leaching by exposure to the field. Based on the results, it can be concluded that the preservative treatment with burnt oil was efficient, to provide the woods a greater biological resistance, especially the use of the oil with lower viscosity (SAE 10). The higher retention rates and low mass loss due to biological deterioration were obtained when employing the burnt oil SAE 10, and on the other hand also showed the highest rates of leaching. Keywords: wood preservation, simple immersion, oily preservative, tropical wood. DOI: http://dx.doi.org/10.14583/2318-7670.v04n03a04