**5.3 Results**

**Figure 10** shows the concentrations as a function of time according to the fitted kinetic parameters data.

Analyzing **Figure 10**, it is observed that the curves generated using the fitted parameters represented the experimental data satisfactorily. **Table 15** presents the process specifications obtained after a sensitivity analysis, aiming to simulate a column with optimal operating conditions. **Figure 11** shows the composition profile in the liquid phase as a function of the column stage number (1 = condenser and 13 = reboiler).

The conversion of glycerol obtained for the operational conditions defined for the simulation was 98.2%, indicating the reaction occurred inside the column.

The SOLKETAL stream in **Figure 9** has 99.53% solketal and the WATER stream consists of 99.82% water, on a mass basis. Thus, the simulations show that the

**Figure 10.** *Experimental and calculated concentrations (80°C).*

*Distillation Processes - From Solar and Membrane Distillation to Reactive Distillation…*


**Table 15.** *RDC column specifications.*

methodology employed results in a high purity solketal product stream with solketal conversion superior to 98%. However, additional studies are needed to assess the effect of possible intermediate reactions on the process yield.

## **6. Conclusions**

In this chapter, a general introduction regarding reactive distillation technology and its application to the biodiesel production process was presented. A literaturebased mathematical model to describe reactive distillation columns was discussed, along with experimental and simulation studies developed by the authors of this chapter, using commercial software such as Aspen Plus.

**Figure 11.** *RDC column liquid phase composition profile.*

*Reactive Distillation Applied to Biodiesel Production by Esterification: Simulation… DOI: http://dx.doi.org/10.5772/intechopen.102667*

In the case study of biodiesel production through the esterification of a low-cost feedstock, the application of an optimized reactive distillation column promoted an improvement of approximately 70% about FFA conversion. The resulting product stream attained purity above 98% in relation to alkyl esters. Additionally, the production of solketal aiming at the valorization of a co-product of the biodiesel production process (glycerol), was studied through the development of a flowsheet in the Aspen Plus simulator, resulting in a solketal stream with purity above 99%.

The results obtained through the developed studies indicate that the reactive distillation technology, applied to fatty acid esterification reactions for the production of biodiesel and ketalization of glycerol for the production of solketal, is promising and attractive in technical terms, however, further studies are necessary to analyze the economic feasibility of both processes.

### **Acknowledgements**

The authors thank UTFPR and Sinochem Petroleum Brazil Limited (project 001/2019) for financial support.

### **Author details**

Guilherme Machado1 \*, Marcelo Castier<sup>2</sup> , Monique dos Santos<sup>3</sup> , Fábio Nishiyama<sup>1</sup> , Donato Aranda<sup>4</sup> , Lúcio Cardozo-Filho<sup>5</sup> , Vladimir Cabral<sup>5</sup> and Vilmar Steffen<sup>6</sup>


\*Address all correspondence to: guilhermed@utfpr.edu.br

© 2022 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
