VALIDAÇÃO DO USO DO EQUIPAMENTO ISPEC Q100 NO CONTROLE DE QUALIDADE DA MISTURA DIESEL-BIODIESEL

Abstract

Nowdays, biodiesel s standardization for quality control in Brazil comprises two standard groups and within these methods, validation is essential to ensure the success in fuel s quality control. The aim of the present work was validating the use of the equipment I-SPEC in analysis of biodiesel blends with diesel, from a mixed matrix (vegetable, animal). The equipment, based on spectroscopy impedance, analyzes four parameters in biodiesel (total glycerol content, acidity index, residual content of methanol and biodiesel blend in diesel). The procedure involved analyzes of biodiesel, blends of biodiesel:diesel, and diesel samples by infrared (FT-IR) technique, correlation curves analysis of IV x I-SPEC in duplicate, quintuplicate sample and different analysts. The obtained data were subjected to the Z Score test (Zanalist1 = 0.0 and Zanalist2= 0.335) and the Student's T test (tcalculated1 = 0.0 and tcalculated2 = 0.75), with 95% level of confidence and 4 degrees of freedom, demonstrating that the method generates real results, compared to the standard technique (FT-IR). Correlation I-SPEC x FT-IR showed good linearity (r = 0.997) and low relative difference (error < 2.0%) ensuring that the methodology can be applied to study blend with equivalence of results, within their limitations of precision, and contemplating the content of biodiesel in diesel, currently regulated by Brazilian legislation (5%). The equipment provides portability, low maintenance costs and low complexity of operation compared to standard techniques (FT-IR, CG, HPLC) and therefore could be used in field assessments. As disadvantage, we can mention: the use of sensors limited to only once, the results are generated for biodiesel blends (biodiesel:diesel) in absolute values (with only one significant figure), the method will not be able to detect contamination of biodiesel with vegetal oil, the need of the equipment be used in environment with low temperature variation (± 1.0 º C) to perform the analysis. With the results from this study can be concluded that, even considering the disadvantages, the new procedure is similar, in terms of applicability to standard method, FT-IR. So the I-SPEC equipment appears sufficient to allow the determination of biodiesel blends : diesel, within the range studied (2% to 10%), ensuring security of the analytical results studied.