Quality Control of Biodiesel Content of B7 Blends of Methyl Jatropha and Methyl Crambe Biodiesels Using Mid-Infrared Spectroscopy and Multivariate Control Charts Based on Net Analyte Signal
2016
Sitoe, Baltazar Vasco | Mitsutake, Hery | Guimarães, Eloiza | Gontijo, Lucas Caixeta | Santos, Douglas Queiroz | Borges Neto, Waldomiro
In this work, mid-infrared spectroscopy and multivariate control charts based on the net analyte signal (NAS) were applied for quality control of B7 (7% biodiesel and 93% diesel) biodiesel/diesel blends of jatropha oil methyl esters (JOME) and crambe oil methyl esters (COME) relative to the biodiesel content. The construction of the multivariate control charts was based on the decomposition of the spectral signal of samples prepared within quality specifications. Three charts were generated: (i) a NAS chart to monitor the content of the biodiesel in the blend, (ii) an interference chart to monitor the diesel content, and (iii) a residual chart to monitor any systematic variations. For each chart developed, statistical limits were established using the same samples prepared under normal operating conditions, with biodiesel content between 6.5% and 7.5%, considering the range of ±0.5% (v/v) permitted by the Brazilian National Agency of Petroleum, Natural Gas, and Biofuels. To validate the control charts, new in-control and out-of-control samples relative to the biodiesel content were prepared. Of the two sets of out-of-control samples, the biodiesel content of one set (D) was below 6.5% (v/v) and the other set (E) was above 7.5%. The third set (C) of validation samples was prepared with biodiesel content within control of the quality specifications. The analytical methodology developed for each model (JOME and COME) was rapid, efficient, and able to correctly monitor the compliant and noncompliant samples relative to the biodiesel content in B7 biodiesel/diesel blends, demonstrating that this methodology is an alternative route to be used by the supervisory bodies for quality control of these types of biodiesel.
显示更多 [+] 显示较少 [-]