Q2. What is the main reason why biodiesel is used in soy?
Vegetable food oils, such as soybean 46 oil, rapeseed oil, palm oil and sunflower oil are used in more than 95 % of biodiesel 47 production plants throughout the world [4].
Q3. How much of the biodiesel production costs are derived from vegetable oils?
57 Virgin vegetable oils might account for up to 95% of the biodiesel production costs [6]; 58 therefore, raw-material diversification might have significant impact on improving the 59 economic viability of the process.
Q4. How many experiments were conducted in order to evaluate the biodiesel production process?
In order to evaluate the biodiesel production process, 14 preliminary experiments were 218 conducted, by varying the reaction temperature, time, ethanol:oil molar ratio and 219 homogeneous catalyst (NaOH) concentration aiming to select the best conditions to 220 obtain high conversion and identify key reaction parameters.
Q5. How much Na was present in the membrane purified product?
The 417 membrane purified product presented 69 ppm of Na, whereas the product purified with 418 the resin presented 108 ppm of Na.
Q6. What were the conditions used for the conversion of ethanol to oil?
351 Taking into account the results obtained during preliminary studies and also that the use 352 of high alcohol:oil molar ratios in the transesterification reaction is known to 353 significantly increase separation and purification costs [20], the optimized conditions 354 were selected as 45 ºC and 6:1 ethanol to oil molar ratio.
Q7. What was the reaction temperature at which the experiment was conducted?
Taking into account the great amount of work on ethanolysis 230conducted at 80 C, initially, experiments were conducted at that temperature and by 231varying the ethanol:oil molar ratio, the catalyst concentration and the reaction time.
Q8. What were the experimental planning for the 320 experiments?
The 319 experimental planning included performing all experiments in duplicate except for the 320 central point that was performed in triplicate (19 experiments were performed).
Q9. how many ethanol:oil ratios were used in the same experiment?
It can be seen that, using a 9:1 ethanol:oil molar 326 ratio, minor effects were found on varying the temperature; in this case, the purity was, 327 in average 92.3 ± 0.7 and the viscosity 4.76 ± 0.04 mm2 s-1. 328 When using 6:1 and also when using 12:1 ethanol:oil molar ratio, a more significant 329 effect was found by varying the temperature, with the highest purity being obtained at 330 40 ºC and 6:1 ethanol:oil molar ratio and at 30 ºC, using 12:1, being in both cases very 331 similar (close to 96 wt.%).
Q10. What is the way to achieve a high ethanol:oil ratio?
The results showed that to achieve high 449 conversions at a relatively low temperature, of 30 ºC, a high ethanol:oil molar ratio is 450 required (12:1); on the other hand, no benefit results from increasing the temperature up 451 to 50 ºC using such a high ethanol:oil molar ratio.
Q11. What was the reaction temperature at which the product was removed?
To do that, after 1 h 255 the reaction was stopped, the products were settled and glycerol was removed as 256 described in section 2.2.1.
Q12. How is the biodiesel process compared to the methanolic route?
The ethanolic route is in fact 84 more promising; however, the process is much more sensitive and it still needs to be 85 optimized, namely regarding reaction conditions and product separation constraints, to 86 be competitive with the methanolic route [17].