Determination of Na, K, Ca and Mg in biodiesel samples by flame atomic absorption spectrometry (F AAS) using microemulsion as sample preparation

Direct determination of sodium, potassium, chromium and vanadium in biodiesel fuel by tungsten coil atomic emission spectrometry

“…No piece of legislation establishes maximum levels allowed for these elements in biodiesel fuel, but the LODs presented in Table 3 may be adequate for eventual regulations. Table 4 presents the comparison between the procedure described in this work and other methods proposed for biodiesel analysis [8,12,[30][31][32][33][34]. As it can be seen, WCAES sensitivities are comparable to FAAS and ICP OES, without the need for more complex sample treatments such as microemulsion preparation.…”

Interaction of Selected Fuels with Water: Impact on Physical Properties and Microbial Growth

“…These metals can be used as an evaluative tool to estimate total salt concentrations in the fuels. Samples were prepared as microemulsions using a method modified from the literature for flame and graphite furnace analysis of fuels for trace metals [36][37][38][39][40][41][42]; using 2.5 mL twice distilled (in-house to enhance purity) reagent grade n-propanol (99.5% Sigma-Aldrich), 0.5 mL of the desired fuel, and 100 μL of 0.2% (v/v in deionized H 2 O) trace metals grade 70% HNO 3 (Sigma-Aldrich). All volumes added were massed as well for enhanced precision in measurements.…”

Chemical Analysis of Biomass - A Review of Techniques and Applications

“…Na, K, Ca e Mg podem ser determinados em biodiesel utilizando-se a mesma técnica analítica, porém com um preparo da amostra por meio de formação de micro emulsões, o que proporciona um aumento da estabilidade do sinal analítico. 36 Outro exemplo é na determinação de glicose e etanol em processo de obtenção de etanol de segunda geração, a partir de biomassa lignocelulósica, com o uso da espectroscopia Raman. Neste caso, necessita-se de pouca preparação da amostra, com esta sendo somente filtrada.…”