MagnesolÒ purification
About 50 g sample of unpurified biodiesel was transferred to a
125 mL Erlenmeyer flask and the purification was performed in a batch mode under heating at 65 °C and stirring. The concentration of the adsorbent in the sample was 1% (w/w) and time of purifica- tion was 20 min [8]. The sample was then filtered through a simple funnel with filter paper to remove the adsorbent and stored for la- ter analysis. The purification was done in duplicate.
RHA purification
For purification using RHA it was used the same procedure of MagnesolÒ (20 min of stirring at 65 °C) but with concentrations of 1%, 2%, 3%, 4% and 5% (w/w). The RHA did not suffer any previous treatment. The purified biodiesel was filtered through a simple funnel with filter paper to remove the adsorbent and stored for la- ter analysis. Each one purification was done in duplicate.