Microwave-assisted digestion using diluted nitric acid for further trace elements determination in biodiesel by SF-ICP-MS

Biodiesel Trace Element Analysis by Energy Dispersive X-ray Fluorescence Spectrometry Using Magnetic Solid-Phase Microextraction

“…The maximum concentrations were found to be 166 μg kg –1 for Cd, 106 μg kg –1 for Cr, 137 μg kg –1 for Pb, 82 μg kg –1 for V, and 92 μg kg –1 for Mo. Previous works have also reported values at the μg kg –1 level for the five target elements. ,,,− The presence of some transition metals, even in low concentrations, could promote the oxidation of biodiesel, leading to adversely affect engines operation through corrosion, deposit formation, and fuel injection failure. In addition, toxic metals can be considered environmental pollutants since these species can be released into the atmosphere during the burn of the fuel …”

A simple, fast and inexpensive approach to quantify low concentrations of iron in biodiesel by voltammetry after extraction induced by microemulsion breaking

“…23,24,47 Moreover, the presence of those metals has been investigated as triggers for the oxidation of biodiesel, 9–13,48 and analytical methods were developed for their determination in this matrix. 14,26,31,36,49…”

“…23,24,47 Moreover, the presence of those metals has been investigated as triggers for the oxidation of biodiesel, [9][10][11][12][13]48 and analytical methods were developed for their determination in this matrix. 14,26,31,36,49 The study of interferents was carried out in cells containing 50 mg L −1 Fe and other inorganic species in the Fe : species ratio varying from 4 : 1 to 1 : 10, as shown in Table 1. No signal related to the potential interfering species was observed close to the reduction peak of Fe(III)-PAN.…”

Microwave-induced combustion for petroleum coke digestion: a promising sample preparation strategy for subsequent elemental determination

“…21 In addition, these methods frequently use alternative energy, such as microwave radiation (alone or also in a combination with ultraviolet or ultrasonic radiation), 22 in order to obtain high efficiency of digestion even using diluted solutions. [23][24][25] Based on these aspects, the microwave-induced combustion (MIC) method could be promising to perform the decomposition of petroleum coke, as demonstrated in this study, with high efficiency and contrarily to the official method, following the green chemistry recommendations. This method is based on the combustion of the sample, in general rich in carbon, in the presence of a rich oxygen atmosphere, where the sample combustion was induced by the microwave radiation.…”