Deacidification of organic liquid products by fractional distillation in laboratory and pilot scales

Abstract

This work aims to investigate the de-acidification of organic liquid products, obtained by catalytic cracking of palm oil (Elaeis guineensis Jacq) using Na2CO3 as catalyst, by fractional distillation. The distillation of OLP carried out in laboratory, using columns of different heights with and without reflux, and in pilot scale. OLP and distillation fractions physicochemical characterized for density, kinematic viscosity, acid value, saponification value, refractive index, ester index, free fatty acids, flash point, and copper strip corrosion. The OLP analyzed by GC–MS and FT-IR, and light diesel-like fractions by FT-IR, NMR, and GC–MS. The experiments carried out in laboratory scale with and without reflux showed biofuels (distillates) yields between 62.15 and 76.41% and 71.65 and 89.44% (wt.), respectively, while that in pilot scale was 32.68% (wt.). For the experiments in laboratory scale, the yields of distillates decrease exponentially with column height, with and without reflux, while those of bottoms products increase exponentially. In addition, the yields of distillates and gas increase with increasing Na2CO3 content, while that of bottom products decrease. The yield of light diesel-like fractions, with and without reflux ranged between 48.82 and 63.18, and 20.23 and 21.43% (wt.), respectively. The column height had no significant effect on the density of distillation fractions, with and without reflux. The densities of gasoline, kerosene, and light diesel with reflux, superpose exactly those of kerosene, light diesel, and heavy diesel without reflux. The kinematic viscosity of distillation fractions decreases with increasing column height for the experiments with and without reflux, while the acid values decrease. For the distillation experiments in pilot scale, the acid values of gasoline, kerosene, and light diesel-like fractions were 0.33, 0.42, and 0.34mg KOH/g. FT-IR of distillation fractions in pilot scale and NMR of light diesel-like fraction in laboratory scale, column height of 50cm, under reflux identified the presence of aliphatic hydrocarbons and the absence of carbonyl groups. The GC–MS analysis identified in OLP composition 92.84% (area.) hydrocarbons and 7.16% (area.) oxygenates. The light diesel-like fraction contains 100% hydrocarbons with an acid value of 0.34mg KOH/g, density of 0.7862g/cm3, and kinematic viscosity of 1.52mm2s−1, proving the feasibility of OLP de-acidification by fractional distillation.