Avaliação da polpa kraft de celulose na purificação de biodiesel de girassol

Abstract

In this work was prepared methyl sunflower biodiesel by transesterification alkaline, the purification step was performed by use of eucalyptus pulp and compared with the process using deionized water. The Kraft pulp was characterized by infrared spectroscopy (FTIR), X-rays (X-RD), viscosimetric molecular mass, water content, morphological analysis and levels of α-cellulose and hemicellulose. After purification were evaluated impurities free glycerol, methanol, water and alkali metal content alcalinos (Na+, K+, Ca2+ e Mg2+). The cellulose fibers were fractionated into three sizes different by sieving (sieve pore sizes of 500, 600 and 1,180 μm) and studied in order to find the best size retention of contaminants. The cellulose mass added to the column was another important process parameter, in this case, was varied in 0.2 g and 1.0 g. The pressure exerted on the purification system was evaluated in both cases, first under atmospheric pressure and the second by a pressure generating pump of 1.22 atm column containing biodiesel Furthermore, the column diameter was varied between 1.0 and 1.3 centimeters, to see if any improvement in purification. The physicochemical characterization of biodiesel all tests were performed in accordance with the rules and limits set by ANP (National Agency of Petroleum, Natural Gas and Biofuels) for oxidative stability to 110 °C kinematic viscosity at 40 °C, the density 20°C, water content, acid number, residual glycerol and free methanol. The system showed the best performance in the removal of impurities consisted of cellulose fibers 500 μm with a mass of 1.0 g of this material on a column 1.3 cm in diameter, and pressure exerted by the pump. In this condition, the amounts of free glycerol, methanol, and water in biodiesel purified were 0.0081 ± 0.0001, 0.268 ± 0.009% w/w and 636 mg kg-1, respectively. The results indicate that this cellulosic adsorbent is a promising material for biodiesel purification instead of using the wash water, preventing the generation of large volumes of wastewater.